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At my wits end with this '84 2.5L. by Brocephus
Started on: 11-30-2008 12:11 PM
Replies: 35
Last post by: Frizlefrak on 12-03-2008 04:03 AM
Brocephus
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Report this Post11-30-2008 12:11 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

Ok, I have replaced with new or "known good" parts:

New Intake manifold mounting gasket
New throttle body mounting gasket
New air filter housing mounting gasket
New Vacuum line to AutoThermac (flapper valve in air filter housing)
New Vacuum line to PCV valve
New Vacuum line to evap canister
New Fuel filter
New Coolant Temp sensor (for computer)
Known good IAC motor
Known good MAP sensor and associated vacuum line
Known good Throttle Position Sensor
Known good EGR valve and associated vacuum line
Known good ECU
Known good Distributor

------------------------------------------------------------------------------------------------------------------------

I have removed both engine wiring harnesses, cleaned them, and ensured wiring insulation was not abraided or deteriorated. I did not clean the goo out of the connectors as I figured that was a corrosion inhibitor. I then re-taped the full length of both wiring harnesses so as to prevent further deterioration of the corrugated plastic and wire insulation. Re-installed with great care.

Timing has been set to 8° BTDC, in accordance with instructions found on http://fierodomain.com/content/view/175/100/.

I tested the TPS throughout its entire range with an ohm meter - no dead spots or wild spikes.

I verified the voltage of the MAP sensor signal wire to be 4.5V with key on/engine not running and 2.9V with engine running @ 1000 rpm. (Scale found on Alldatapro. Instructed to take reading at 10" of Hg (vacuum). My location is 840' above seal level.)

I wasn't able to verify the voltage or resistance of the coolant temperature sensor, but I did replace it with a new part.

I verified the operatio of the EGR by depressing the diaphram and plugging the hole. Valve stayed open until hole was uncovered.

Unable to test the IAC motor as I'm not sure how to go about it, but I did note that with the key on/engine off, it was going in and out repeatedly.

------------------------------------------------------------------------------------------------------------------------

Fuel is less than a month old.
Oil was changed less than two months ago.
Coolant was new when engine was installed in Oct. 07.

------------------------------------------------------------------------------------------------------------------------

Symptoms:
While at idle, engine runs very smooth.
Throttle response is good.
When throttle is snapped quickly, engine revs all the way to 5000 rpm with no hesitation.
When throttle is depressed gradually, engine revs all the way to 5000 rpm with no hesitation.
Sitting still, you'd swear this car ran beautifully.
As soon as a load is placed on it however, the car bogs down horribly and struggles to stay running.
Once in motion, engine springs to life and pulls very hard to 3000 rpm.
Once past 3000 rpm, engine looses all power and will not rev higher than 3000 rpm.
If gas pedal is released slightly, it is possible to find a "sweet spot" where the car will suddenly be able to make power again. If accelerator is pressed too hard, too fast, engine will suddenly lose power again.
Even in this condition, it is possible to go in excess of 70 mph, but it takes nearly three times longer than normal and a lot of working with the gas pedal.
During the short test drives I have taken, the check engine light has come on: DTC 33 and 34. MAP sensor- too much and too little voltage. As soon as I get my '94 GMC Sonoma back from a friend, I will swap the MAP sensor again and see if results are the same in my truck and in the Fiero. (They use the same MAP sensor.)

I have tried everything I can think of to try.


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Frizlefrak
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Report this Post11-30-2008 12:31 PM Click Here to See the Profile for FrizlefrakClick Here to Email FrizlefrakSend a Private Message to FrizlefrakDirect Link to This Post

They need 3 things to run correctly;

1. Suitable compression
2. The correct mixture of fuel and air for a given engine speed and load.
3. A suitably strong spark delivered at the correct time.

If those 3 conditions are met, they run. This applies to any internal combustion engine built in the last 120 years.

I'm assuming compression is good on the engine, but maybe I shouldn't. How many pounds of compression on each cylinder? Let's look at pressure and variance.

That said, what is your fuel pressure under each of these operating conditions? I don't want to know if it's getting fuel....it will start, so that much is obvious....I want to know EXACTLY how many pounds under each circumstance. The TBI system needs between 9-13 psi to run correctly, but really, any less than 10 psi and performance will fall off dramatically. Low fuel pressure may be sufficient to rev with no load on the engine...but once it's under strain, it falls on it's face. There is no schrader valve on a TBI system, which means a low pressure gauge, T fittings, hose, and clamps. No fun to check, but essential. If you can route the gauge over the roof and tape it to the windshield, you should be able to read it as you drive.

I also want to know if the injector is spraying a nice, conical mist under all conditions....or if it may need to be serviced. This can be tough to verify moving without a chassis dyno....any access to one? If not, a buddy who's willing to ride in the trunk? (just kidding )While were at it, how many inches of vacuum at idle? Does the needle hold steady or waver?

These tests will either eliminate the mechanical health and fuel systems as suspects, or make us dig deeper. Either situation is OK, it means we're one step closer.

I think you're chasing a phantom with the the emissions and ignition systems (condition 3). Let's back up a bit and ensure the engine is mechanically healthy (condition 1), and the fuel system is up to snuff (condition 2).

And remember to troubleshoot, don't guess. Throwing parts at a problem to fix it can get very expensive in a hurry.

Happy wrenching, and post your results.

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ScottSss
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Report this Post11-30-2008 12:40 PM Click Here to See the Profile for ScottSssClick Here to Email ScottSssSend a Private Message to ScottSssDirect Link to This Post

When you replaced the distributor was the Ignition module changed as well? I am assuming so. Try changing out the ignition coil. Ignition problems always show up while the engine is under load. If this doesn't work try and swap out the ECM. If this doesn't work it is a fuel problem. Have you done a compression test on the motor? It should be 70+psi minimum per cylinder. Look for uniformity across the cylinders. Scott

------------------
Home of 3 1/2 Fieros, a 900HP AWD S10, a 1967 Pontiac Catalina Convertable, a Chevy Avalanche and lots of misc GM parts.

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ScottSss
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Report this Post11-30-2008 12:42 PM Click Here to See the Profile for ScottSssClick Here to Email ScottSssSend a Private Message to ScottSssDirect Link to This Post

Also check for a plugged up catalitic converter

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Nosferatu187
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Report this Post11-30-2008 12:55 PM Click Here to See the Profile for Nosferatu187Send a Private Message to Nosferatu187Direct Link to This Post

 
quote
Originally posted by ScottSss:

Also check for a plugged up catalitic converter


Haha, I was just going to post that too.

Mike

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Brocephus
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Report this Post11-30-2008 01:09 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

Thanks a ton for that info and I will certainly be in constant contact with you. As a military mechanic, I'm a great parts changer, but it hasn't been until recently that I have started honing my troubleshooting skills. But as far as the parts I have changed, I have a spare Fiero that ran like a champ until the head gasket gave up at 167,000. So the sensors have been free.

Of the seven bolts that hold the the intake manifold to the head, three were finger tight and came out without tools. I found this during my search for vacuum leaks by squirting a bit of starting fluid at the base of the TB, vacuum lines, and intake gasket. So without a doubt, the intake gasket needed changing. Also changed the oozing pushrod cover gasket while I was in that deep.

I performed a compression test less than a month ago and all but one cylinders were at or near 135 psi. #3 was at 110 psi. To do this, I disconnected the power to the fuel pump and pulled the electrical connector off of the injector. I removed all spark plugs, threaded my pressure gauge snugly into the spark plug hole, and cranked the engine for 5 seconds. I repeated this for all four cylinders.

Fuel injector gives a great looking, cone-shaped spray. I can't be certain of pressure at this time, but as soon as I can get a reading, I'll let you know. No access to a dyno, and no buddies willing to ride in the trunk. I have kids though. Is that legal?

When i checked it yesterday, the vacuum at 1000 rpm was 20 in. of Hg.

Lastly, I just noticed that in all the drawings of the distributor I have seen, the hold-down screws are at the 7 o'clock and two o'clock positions. Mine are at the 10 o'clock and 4 o'clock positions. Is it possible that my distributor is 1/4 turn out and if it is, would it matter as long as my plug wires were placed accordingly?

Ok, I'm off to see if I can get a fuel pressure reading.

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Brocephus
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Report this Post11-30-2008 01:18 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

Catalytic converter? What catalytic converter?

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Nosferatu187
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Report this Post11-30-2008 01:45 PM Click Here to See the Profile for Nosferatu187Send a Private Message to Nosferatu187Direct Link to This Post

 
quote
Originally posted by Brocephus:

Catalytic converter? What catalytic converter?


Well if you have no catalytic converter then my opinion is that it's likely not the problem.

Mike

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Frizlefrak
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Report this Post11-30-2008 02:37 PM Click Here to See the Profile for FrizlefrakClick Here to Email FrizlefrakSend a Private Message to FrizlefrakDirect Link to This Post

 
quote
Originally posted by Brocephus:


Fuel injector gives a great looking, cone-shaped spray. I can't be certain of pressure at this time, but as soon as I can get a reading, I'll let you know. No access to a dyno, and no buddies willing to ride in the trunk. I have kids though. Is that legal?



I use nephews since I don't have kids, but if you have access to kids, they're perfect for this (might wanna strap 'em down though)

 
quote
Originally posted by Brocephus:


Ok, I'm off to see if I can get a fuel pressure reading.


Yeah, let's rule out a flaky pump, pulsator, regulator, etc. I'm assuming the filter is good.

As for your distributor question, I haven't worked on a duke in ages, but if your timing is off, it can cause symptoms similar to yours. I would certainly explore it further if there is any doubt. Take the ECM out of the equation and check your base timing again.

A Fiero will certainly fine tune your troubleshooting skills. Couldn't pick a better car.

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Lou6t4gto
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Report this Post11-30-2008 03:00 PM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoDirect Link to This Post

HERE'S WHATS GONNA SOUND LIKE A WACKY ANSWER, HAPPENED TO ME YESTERDAY. the ngine strts runs great, untill I put it in either drive or reverse, the it felt like the emergency brake was on, no power, just wanted to die!. checked the trans fluid, it was down a quart. filled it up, and now it's got all sorts of power, no bog,. you would think, low fluid it would slip ! but it did exactly as you posted. maybe when it's low the converter tries to lock up ???

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Brocephus
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Report this Post11-30-2008 04:00 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

I was able to get a fuel pressure reading, but only with the ignition switch on, engine not running, fuel line disconnected from the throttle body and plugged directly into a vacuum/fuel pressure gauge. It registered 4.5 psi and not a penny more.

I'm pullin' a fuel tank (edit: again), ain't I?

[This message has been edited by Brocephus (edited 11-30-2008).]

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Brocephus
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Report this Post11-30-2008 04:08 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

 
quote
Originally posted by Lou6t4gto:

HERE'S WHATS GONNA SOUND LIKE A WACKY ANSWER, HAPPENED TO ME YESTERDAY. the ngine strts runs great, untill I put it in either drive or reverse, the it felt like the emergency brake was on, no power, just wanted to die!. checked the trans fluid, it was down a quart. filled it up, and now it's got all sorts of power, no bog,. you would think, low fluid it would slip ! but it did exactly as you posted. maybe when it's low the converter tries to lock up ???


This car's saving grace is the fact that it's a manual 4-speed. I'm not real fond of 4100 rpm at highway speeds, but at least I don't have to worry about a 24 year old automatic transmission, hehe. Clutch is new, too. :-)

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86fierofun
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Report this Post11-30-2008 05:07 PM Click Here to See the Profile for 86fierofunSend a Private Message to 86fierofunDirect Link to This Post

was the fuel pump running when you took that measurement? (it shuts off a few seconds after the ignition turns on) I believe it will bleed back a little. You would need the pump running to get a good measurement.

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Brocephus
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Report this Post11-30-2008 06:50 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

Yeah, the highest pressure it attained was 4.5 psi. I was able to rig it so that I could watch the gauge while I turned the key on. I even went so far as to turn the engine over while watching the gauge, and still did not attain any more than 4.5 psi.

What I need to know - is it still necessary to make a run to the hardware store and find a way to test the fuel pressure with the engine running? Or can a diagnosis be made with the readings I have so far?

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Brocephus
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Report this Post11-30-2008 07:12 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

According to Alldata.

Before servicing fuel system components, fuel system pressure must be released. To relieve pressure, proceed as follows:


1. Remove fuel pump fuse from fuse block.
2. Run engine until fuel remaining in lines is consumed. When engine shuts down, engage starter for approximately three seconds to relieve any remaining pressure.
3. With ignition off, replace fuel pump fuse.
4. Remove air cleaner and plug THERMAC vacuum port on throttle body unit.
5. Remove fuel line between TBI unit and fuel filter or between front and rear TBI units on ``Crossfire'' injection systems. Use a suitable back-up wrench to hold flare nut on throttle body when removing line.
6. Install fuel pressure gauge J-29658 or equivalent, between throttle body and filter or, on ``Crossfire'' systems, between front and rear TBI units.
7. Check pressure reading with engine running. If fuel pressure is not between 9 and 13 psi, refer to ``Fuel System Diagnosis.''
8. De-pressurize fuel system, remove pressure gauge and reinstall fuel line.
9. Start engine and check for fuel leaks.
10. Remove plug from THERMAC vacuum port and install air cleaner.

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Brocephus
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Report this Post11-30-2008 08:44 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

I posted the following on a local Louisville automotive website and thought it might be of interest to someone here. It details my recent experience of changing my intake gasket and my attempts to chase down a miss and the above hesitation problem.

----------------------------------------------------------------------------------------------------------------------

For the last two months, I've been battling a miss in my factory Fiero. A miss in this car is horrible because when you've only got 92 hp to start with, you really need ALL the cylinders to do as much as possible.

I changed the plugs, wires, rotor cap, button, air filter, and O2 sensor; tested the MAP, TPS, IAC, and EGR; hired a priest, a rabbi and two voodoo masters and all I ended up with was a fondled Fiero with a kosher miss and a shrunken head.

In a fit of blind rage, I put it all back together, drove it into the back yard, grabbed a can of starting fluid and a match, and with a demonic look in my eyes, proceeded to flood the entire engine compartment with starting fluid. Just as I was getting ready to light the match however, my engine suddenly perked up and the rpms shot through the roof. I shut the car off and walked away for oh.... three days.

Once I was again sane, I started the car and it was still missing. With surgical precision, I squirted a tiny amount of starting fluid around the base of the throttle body, vaccuum lines, and finally the intake manifold gasket. It was at the mani gasket that I noticed a marked increase in rpms. I grabbed a hammer, a pair of pliers and my leatherman and went to work.


As you can see, the EGR ports were clogged solid. The right side is completely blocked and the left side is to, but the gunk stayed on the gasket (as seen at top of 2nd photo.) :barf:





Of the seven bolts holding the intake to the head, I was able to remove three of them without tools. The area above the EGR port was obviously not sealing and the area (not shown) on the rightmost side was sucking air in the worst way.


EGR port. Nasty, caked and damn near plugged shut.


In this shot, you can see the induction ports are black and sticky with soot. Listen folks, when your service advisor tells you that your car needs an Induction Service, he's not jerking your chain. Cleaning this mess up required a stainless steel wire cup brush at 10,000 rpms in a Dremel and almost 4 hours of steady work. How hard is it for you to breathe with a noseful of junk? It's no different for your engine.


The intake as it looked when removed. I think it's supposed to be shiny aluminum. Time for Brocephus to work his magic.


Enter the Dremel, a wire brush, a small military gun "tooth"brush, and the patient determination that can only be found in a lunatic. Two days and no less than eight hours later, I emerged from my cave, unharmed and smiling..... twitching, but smiling.

The EGR runs and port "post-Brocephus".




Hard to tell, but the intake ports are just as shiny and polished as the EGR port.


You know your wife is cool as hell when she comes home, catches you washing your intake manifold in the kitchen sink, kisses you and makes a pot of coffee.


Clean and ready to go back in.


Yes.... I have my distributor cap labeled. I scratched the numbers into the plastic and then hit them with a white paint pen.


A little bit of cleaning left to do on the engine and it'll all be ready to go back together.

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Frizlefrak
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Report this Post11-30-2008 09:35 PM Click Here to See the Profile for FrizlefrakClick Here to Email FrizlefrakSend a Private Message to FrizlefrakDirect Link to This Post

 
quote
Originally posted by Brocephus:

I was able to get a fuel pressure reading, but only with the ignition switch on, engine not running, fuel line disconnected from the throttle body and plugged directly into a vacuum/fuel pressure gauge. It registered 4.5 psi and not a penny more.

I'm pullin' a fuel tank (edit: again), ain't I?


Probably. Deadheading the pump directly should have achieved much more pressure. You can run 12V directly to terminal G on the ALDL, which will cause the pump to run continuously for testing purposes. Otherwise, the ECM energizes the fuel pump circuit for approximately 2 seconds at key on, and then shuts it off unless it detects the engine is cranking or running.

Try running a T fitting to your gauge so you can test pressure while the engine is running and under a variety of running conditions. If all you're getting is 4.5 psi, it ain't gonna run on that. Change your filter if you haven't already and test again. Also pinch off the return line and see what the pressure does. If it's still low, drop the tank. Check the pulsator and see if it has split or come off....or just replace with fuel injection hose. If all of the above is good, figure on a fuel pump.

Me thinks you're getting closer to the problem. And I've dropped a Fiero tank 3 times now....I feel for you. I use a transmission jack and it ain't so bad...just getting that huge filler hose off and back on is loads of fun.

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Brocephus
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Report this Post11-30-2008 10:41 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

Get ready for a chuckle because I just replaced the tank in this damn thing this summer. I now get to kick myself and take a well-deserved laughing from the community for not replacing the fuel pump when I had it out.

Lucky for me, I'm on "E".

Lucky again for me, my hoses were not all that difficult to pull off or put back on.

While I'm at it, I'd like to see about replacing the fuel filler neck as mine is rusty as hell. The car was owned in Michigan for most of its life before I bought it on Ebay after the guy moved to TN. I bought it from TN because I figured it would NOT have spent much time in the rust belt.

Anyway, I'll be headed to the hardware store tomorrow to buy the necessary fittings to install a fuel pressure gauge. Many thanks for the help.

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Rodrv6
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Report this Post12-01-2008 12:49 AM Click Here to See the Profile for Rodrv6Click Here to Email Rodrv6Send a Private Message to Rodrv6Direct Link to This Post

Since your fuel pressure is so low, check the rubber fuel line inside the tank that connects the pump to the fuel line. I had an 84 that also would not run well under load, and my fuel pressure was about 5 psi. Turned out that the rubber line was split. I replaced it with a piece of fuel hose and all was well.

------------------
Rod Schneider, Woodstock, Ga.
"You can't have too many toys!"
1988 Fiero GT
1966 Porsche 911
Van's RV-6 airplane-under construction

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Brocephus
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Report this Post12-01-2008 01:36 AM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

I'll be sure to check that, although if I'm going to be elbow deep in that fuel tank again, I'm not comin' back out until I replace the fuel pump, hehe.

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Frizlefrak
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Report this Post12-01-2008 02:47 AM Click Here to See the Profile for FrizlefrakClick Here to Email FrizlefrakSend a Private Message to FrizlefrakDirect Link to This Post

I feel your pain Bro.....





....But the effort paid off nicely....



 
quote
Originally posted by Brocephus:

I'll be sure to check that, although if I'm going to be elbow deep in that fuel tank again, I'm not comin' back out until I replace the fuel pump, hehe.


I would replace the pulsator with fuel injection hose while you're in there. Trust me on this one...I speak from experience. If you think dropping the tank sucks, try doing it twice in one week on the same car. That happened on my 88 4.9 coupe. Had to change it anyway, since car was originally a duke...but the pulsator looked OK. It started once, and fuel pressure fell to zero. Pump still running. I was in denial for the first minute....and on my back for the next hour.

[This message has been edited by Frizlefrak (edited 12-01-2008).]

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ly41181
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Report this Post12-01-2008 07:19 AM Click Here to See the Profile for ly41181Click Here to Email ly41181Send a Private Message to ly41181Direct Link to This Post

Love your pics man. They will help me with my car.

Josh

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Brocephus
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Report this Post12-01-2008 08:08 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

Josh, glad to help. I like documenting my work so others can see what I'm doing instead of just reading about it. I'm known far and wide for my epic posts anyway, so pictures tend to cut down on some of the wordiness, hehe. Stay tuned, there'll be more pics.

Friz, I wasn't fond of trying to rig something with a gauge attached just to run it down the road for 200' and back, so I bought a fuel pressure gauge with a male 1/8"-NPT nipple at O'Reilly's. It was a Mr. Gasket, Fuel Pressure Gauge, part #1561. I then went to Home Depot with the hope of finding just the right combination of fittings to fit them to my fuel line. As I approached the pegboard wall with all the plumbing stuff hanging from it, the Fiero gods took pity on me and directed my eyes to the perfect fitting. It had a 3/8" compression fitting on each end and a female 1/8"-NPT Tee. The fitting is brand name "WATTS", part # A-139 "Ice-maker splice tee".

I brought all my goodies home, made my measurements, removed and cut my steel fuel line, reamed out the inside and sanded the outside.

edit: I slapped it all together, installed it as quickly as I could, started it up and noted 7 psi of fuel pressure. When I gassed on it, my fuel pressure dropped as low as 3.5 psi. Then I noticed my fittings were leaking fuel ever so slightly. I removed and did the following.

I slid my nut and farrell onto the fuel line and then put a center punch down inside the fuel line. I smacked it sharply with a brass tap hammer until the end of the fuel line appeared to be ever so slightly flared.


I then applied some "Loctite" 620 retaining compound to the steel fuel line and attached it to the tee. Repeat for other side and in 24 hours (after the Loctite fully cures) I will have a permanent fuel pressure gauge in the engine bay.

Complete engine bay. When I pop the hood and peek inside, I don't see a mess of wires and lines going all over the place. But when I see it in a picture, it looks awful.


Fuel Pressure Gauge close-up.


Backside showing assembly.


And another shot just for the heck of it.


Things I did that you shouldn't.

If you choose to do this, cut your fuel line exactly in half. Do NOT get too close to the bends because the tube there is not round. Compression fittings need perfectly round tube in order to seal properly.

I will be looking to replace my factory line with something that will seal a little better as my factory fuel line's outer surface has grooves in it that probably stem from the extruding process when it was made.

Don't even think about tightening the fittings while it is mounted in the car. The flimsy little fuel filter clamp will not take the pressure required for you to tighten the compression fittings and the other end is in your throttle body...your aluminum throttle body. I fitted the line in loosely, used a paint pen to mark the position the fittings needed to be in, removed it and then tightened them with the tee-fitting in a vise.

Another reason not to tighten the fittings with it installed in the car: there will be gasoline vapors present. All you have to do is slip off a fitting and bounce a tool off of something. This could throw a spark and ruin your day. Prior to doing any work on a fuel system, Alldatapro reminds you to have a Class B fire extinguisher within easy reach of the car and another within walking distance. You just never know and there are too few of these cars left as it is.

Be safe, mod often, and have damn good time.

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maryjane
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Report this Post12-02-2008 04:05 AM Click Here to See the Profile for maryjaneSend a Private Message to maryjaneDirect Link to This Post

I just temporarily put my FP gage in where the fuel filter is. Just long enuf to get a pressure reading.

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ltlfrari
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Report this Post12-02-2008 09:07 AM Click Here to See the Profile for ltlfrariClick Here to visit ltlfrari's HomePageClick Here to Email ltlfrariSend a Private Message to ltlfrariDirect Link to This Post

what ever happened to the Nissan swap?

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Brocephus
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Report this Post12-02-2008 12:45 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

MaryJane, I did that, but just to make certain, Friz wanted to know what my FP was while under load. I was showing 4.5 psi with just the key on/engine off. Once I got this thing installed, I was showing 7 psi with the engine running. The Iron Duke needs 8-13 psi to run well, so I'm back inside to thaw out for a minute. Laying under my Fiero on cold concrete wasn't on my top ten list of things I really wanted to do, but if you have to do it, I'd rather lay under a Fiero than any other car.


 
quote
Originally posted by ltlfrari:

what ever happened to the Nissan swap?



It's comin' along, but unfortunately I've been unemployed since Feb. 15th of this year. As you can imagine, all progress has ceased due to budget constraints. I'm going to need almost $325.00 to get the Nissan Pulsar ECU (1.6L, NA) reprogrammed with the CA18DET (1.8L, turbo) image. Once that is done, all that will be left is plumbing the coolant, brake, and fuel lines, and figuring out how I'm going to rig a hydraulic slave cylinder to a formerly cable operated transmission. After that it will be all cosmetic and debugging time. I'm not far from completion, I just need a few more bucks to get me down the homestretch.

edit:

1984 Pontiac Fiero on Ebay. $177.50
Nissan Engine / Donor Car. $300.00
Nissan ECU reprogramming. $325.00
Nissan donor car parts sold. -$85.00
Total amount invested so far. $717.50

I think I might still be able to stay under my target amount of $1000 for the whole project. :-)

[This message has been edited by Brocephus (edited 12-02-2008).]

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Ramblin Man
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Report this Post12-02-2008 01:10 PM Click Here to See the Profile for Ramblin ManClick Here to Email Ramblin ManSend a Private Message to Ramblin ManDirect Link to This Post

 
quote
Originally posted by maryjane:

I just temporarily put my FP gage in where the fuel filter is. Just long enuf to get a pressure reading.



Well that was an idea maker!
Why not just make your fuel pressure T fit between the filter and and the TB supply line to begin with and just bolt the thing on? Looks like I have another project to add to the list.

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ltlfrari
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Report this Post12-02-2008 02:52 PM Click Here to See the Profile for ltlfrariClick Here to visit ltlfrari's HomePageClick Here to Email ltlfrariSend a Private Message to ltlfrariDirect Link to This Post

What's involved in reprogramming the ecu? If it's just a case of burning a bin into a rom (and you have the bin file) I can probably burn a chip for you.

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Brocephus
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Report this Post12-02-2008 07:41 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

 
quote
Originally posted by Ramblin Man:Well that was an idea maker!
Why not just make your fuel pressure T fit between the filter and and the TB supply line to begin with and just bolt the thing on? Looks like I have another project to add to the list.


I'm havin' a hard time figgerin' out if you're bein' sarcastic or if you're bein' serious, hehe. I don't know if ya read the whole thread, but I did exactly whatcha talkin' about, lol. Again, I ain't tryin' to be a punk or anything but it's kinda hard sometimes to convey emotion in text, hehehe.

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Brocephus
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Report this Post12-02-2008 07:44 PM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

 
quote
Originally posted by ltlfrari:

What's involved in reprogramming the ecu? If it's just a case of burning a bin into a rom (and you have the bin file) I can probably burn a chip for you.



It would appear that you know more about it than I do bro. The guy I spoke with owns a company in Australia called NIStune. All he does is Nissan ECUs and harnesses. Could it be as simple as finding another person with the same engine as me and copying and pasting the information from his ECU into mine?

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ltlfrari
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Report this Post12-02-2008 09:25 PM Click Here to See the Profile for ltlfrariClick Here to visit ltlfrari's HomePageClick Here to Email ltlfrariSend a Private Message to ltlfrariDirect Link to This Post

I looked on his web site, looks like the eprom on the nissan ecu circuit board is soldered on. Basically you (or I guess they) have to unsolder the original eprom from the board and solder in a socket that is then used to accept his daughter board that contains the new eprom as well as the interface circuitry to the programming software. Very much like the Moates stuff (in fact it interfaces to that as well) and quite a nice solution.

At the very least you would need to unsolder the original eprom and solder in a socket then plug in a reprogrammed eprom, but it requires desoldering and soldering on the ecu circuit board itself, probably something that's best left to someone with experience (and maybe younger eyes than I have these days) doing that sort of stuff.
The GM setup is somewhat simple because the eprom chip is contained within an unpluggable module so even if you want to desolder it, you are not messing with the ecm board directly.

Much as I'd like to help, I think for the cost you are much better letting the guy who knows what he's doing handle the task. Probably money well spent.

I'm impressed though that you've pretty much managed to keep the swap cost to under $1000. My DOHC swap went waaay over budget!

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Dave

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USFiero
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Report this Post12-03-2008 12:41 AM Click Here to See the Profile for USFieroSend a Private Message to USFieroDirect Link to This Post

If you got a rusty filler pipe, you'll probably have to replace the fuel filter every other year. Heck, every Fiero owner should probably do that. Is there any excessive glowing of the exhaust manifold after a high-speed run? Of course, all of this may be moot after the awesome cleanup of the EGR passages. Watch your ignition wires on a dark night, make sure there is no electricity leaking out and putting on a light show.

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Brocephus
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Report this Post12-03-2008 01:01 AM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

It's fixed and runs like a scalded dog!

I made a new thread for the fix so it would be more compatible with the search function as I took the opportunity to make it a how-to thread as well.

The Big Fix

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Brocephus
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Report this Post12-03-2008 01:09 AM Click Here to See the Profile for BrocephusClick Here to Email BrocephusSend a Private Message to BrocephusDirect Link to This Post

 
quote
Originally posted by USFiero:

If you got a rusty filler pipe, you'll probably have to replace the fuel filter every other year. Heck, every Fiero owner should probably do that. Is there any excessive glowing of the exhaust manifold after a high-speed run? Of course, all of this may be moot after the awesome cleanup of the EGR passages. Watch your ignition wires on a dark night, make sure there is no electricity leaking out and putting on a light show.


No kidding about the filler neck. I would love to have changed it while I was in there, but it appears that I'd have to remove a couple of body panels in order to do it.


Thanks for the kudos on my intake clean-up. That was a friggin' mess. I used to see a slight red exhaust manifold now and then but not very often. Could clogged EGR passages cause that?

And as far as the spark plug wires go, nighttime is the only time I even look at them. Any other time is a waste of time. That's how I figured out what was wrong with my GMC Sonoma - the truck that's never let me down and never left me stranded. It managed to limp home about 12 miles with a split spark plug wire boot.

Thanks again folks for the suggestions and encouragement.

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86fierofun
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Report this Post12-03-2008 01:25 AM Click Here to See the Profile for 86fierofunSend a Private Message to 86fierofunDirect Link to This Post

congrats!

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Frizlefrak
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Report this Post12-03-2008 04:03 AM Click Here to See the Profile for FrizlefrakClick Here to Email FrizlefrakSend a Private Message to FrizlefrakDirect Link to This Post

I'm getting all misty eyed.....I love a happy ending...

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