Hello everyone, new to the forum, been lurking around a bit due to my newly acquired car, a beautiful 1988 Fiero Formula 5sp 2.8, yellow.


Long story short, friend was given it as a gift, drove it for a while, died on him, recently sold it to me for dirt cheap after sitting for 6 months ish.

He put brand new tires on it, new front brakes (loaded calipers and rotors), replaced spark plugs, wires and distributor cap.
It ran fine for a while, then on the highway, it began to smoke just a bit, lost all power, barely ran, coasted off, then towed home, been sitting since.

Well i literally just got it today.
Drove it around a little bit to see if i could figure it out.

Symptoms:
High Idle, fluctuates between 1500-800.
Randomly sputters down to sub 500 about to die then picks back up
Under no load idling in the driveway, throttle response is great, revs out to 5k easily
Under load driving, no power, sputters, any excess throttle causes it to buck, sputter more and cut out
Misses under accel.
Strong fuel smell around car and in the cabin
Whice coming from behind drivers seat (assuming fuel pump?)

While i was driving, merging into traffic (of course) it decides to fall on its face and die, i go into the median and coast into a neighborhood, start it up and limp home from there.

My friend and i check the wires, we werent sure of the plug diagram, we looked it up in a maintenance manual for a 82-90something s-10 with the 2.8 v6 this is what we were given:

Can someone please tell me if this is correct for this car?

Soooo onto the interesting part.
The first thing my dad said when he heard it was "its down a cylinder"...great
So he grabs one of his infrared thermometers and shoots the front exhaust manifold looking for a cold cylinder, all read consistent.
We pull off each plug at a time and listen for a change.
As we pull each one, the engine changes pitch and you can tell its down a cylinder.
Well we get to #2 and not a change at all...even better
To top it all off, there's spark, a nice bright arc from the wire to the dist.

So that's where im at now, i fear the worst, a stuck/bent valve or the like.
I was really hoping for a quick fix but of course thats not possible.

Well i've feebly attempted to give all the info i could but if there is anything you need to know, i will gladly answer your questions.
Thank you for your help!

------------------
1988 Fiero Formula 5sp, Yellow. (New toy/Current Project)
1997 Subaru Legacy Outback 2.5 H4 (Possibly the most boring car, but by far the most utilitarian)
1993 Chevy K1500 z71 4x4 (Old Reliable)

Check the compression with a gauge (about $30 at an autoparts store). That'll tell you if it's something serious or just a bad injector, plug, plug wire, etc.

Check your fuel pressure -

You can download a Haynes manual here under Tech
http://www.fieronews.net/fusion/downloads.php

You can purchase a fuel injection fuel pressure gauge at Harbor Freight for 15.99.

Check the fuel pressure - Key on - engine not running - You should get 40-45psi.

Low fuel pressure will give you an ok idle, and will allow you to rev the engine but under any load, where fuel is needed at a higher volume, the engine will fall on its face.

[This message has been edited by phonedawgz (edited 08-05-2010).]

Probably fouled a plug, sounds like a fuel issue to me. If it runs fine sitting but under load has no power, id say fuel pressure is too low. Check pressure and maybe change fuel filter.

is it possible that the whine i hear coming from behind the drivers seat is the fuel pump about do die? I'm just really hoping its not a bad valve or the like because a complete teardown is not in my budget.

Rear (Front) plugs - pull the deck lid off - 4 13mm bolts - two people.

Fuel pump whine - normal

You ARE installing new - and properly gapped plugs when you are finished right?

How does the #2 spark plug wire look? A bad wire or plug for #2 would give you exactly what you indicated - "No power coming from #2"

[This message has been edited by phonedawgz (edited 08-05-2010).]

it has brand new plugs/wires, i have yet to pull any plugs yet, ratchet in hand.

Just to make sure - swap the plug and wire from #2 to somewhere else when your putting it back together - Put the plug in a different cylinder than the one that gets the wire from #2.

That is if your compression test says #2 is fairly normal.

If #2 comes up way bad - then you need not do the plug/wire swap.

Removed the plug from the down cylinder, found this:

Needless to say, im replacing the plugs, someone decided to put Bosch in a GM...
So my next question is, where is the fuel pressure test port? i have the guage here but cant find it in the haynes manual.
Thanks!

The fuel rail - a "block" of alunimun under the upper intake plenum but on top of the lower plenum. On the passengers side - on the top of the alunimun block - near where the two fuel lines from the tank connect to it, is a cap - alunimun - much like a bicycle tire air pressure cap - It almost doesn't look like one. It turns off and under it is the schreader valve

The small cap at the top of the picture


This is how they lay out under the upper plenum


Just to the right of the upper plenum in this picture

[This message has been edited by phonedawgz (edited 08-05-2010).]

Found it, thanks, it was missing the cap so it threw me off a little bit.
I also noticed this random wire routed to the decklid:


Sorry for the orientation, turn your head 90 degrees.
It looks like a botched up harness and i dont see any reason why there would be power to the decklid, any ideas?

That looks like the problem while you are also correct, get rid of the Bosch plugs.
Check the timing while your at it.

quote Originally posted by Williamsr815: It looks like a botched up harness and i dont see any reason why there would be power to the decklid, any ideas?

It is for the power release solenoid on the decklid lock. I believe they are still wired up for it even if it was not optioned, but I could be wrong; I know my friend's 88 coupe is like that, got all the wiring just no switch or release solenoid.

[This message has been edited by topher_time (edited 08-05-2010).]

ok great thanks, just making sure a self proclaimed electrical genius tried to make his own harness.

Good news, compression test read 120 psi on the down cylinder, the gods smile on me!

Ok so new plugs, AC Delco to be exact, and a new air filter...same problems.

It runs on all cylinders now, thats a plus. It takes anywhere between 5-10 seconds cranking to get it to start which is new. Right after we put plugs in it, i went for a drive, much smoother but no power. Suddenly, it stalls and i start it back up, it didnt idle while it was hot but as soon as it cools down, it will idle, albeit rough. On a cold start, it will idle around 1500, drop to an almost stall, pick back up to 2000 rpm, back down to 1500 etc...all in a 30 sec. cycle.

It still pours out fuel as i had to leave my garage after it idling and almost going blind from the fumes.
I pulled out the #2 spark plug, what do you kno, its fouled. The threads are covered in oil and the electrode is covered in deposits.

Any more ideas?

And also, it wont idle any lower than around 1400 no matter hot/cold. I sprayed around the EGR with card cleaner during idle looking for a reaction but nothing...

It could be a plugged cat converter. Seen it happen a million times. thanks lonnie

my main worry is the fouled plug, i have a deal setup to get a cat delete pipe, am i going to run into any problems if i install that?

quote Originally posted by Williamsr815: Ok so new plugs, AC Delco to be exact, and a new air filter...same problems. It runs on all cylinders now, thats a plus. It takes anywhere between 5-10 seconds cranking to get it to start which is new. Right after we put plugs in it, i went for a drive, much smoother but no power. Suddenly, it stalls and i start it back up, it didnt idle while it was hot but as soon as it cools down, it will idle, albeit rough. On a cold start, it will idle around 1500, drop to an almost stall, pick back up to 2000 rpm, back down to 1500 etc...all in a 30 sec. cycle. It still pours out fuel as i had to leave my garage after it idling and almost going blind from the fumes. I pulled out the #2 spark plug, what do you kno, its fouled. The threads are covered in oil and the electrode is covered in deposits. Any more ideas? And also, it wont idle any lower than around 1400 no matter hot/cold. I sprayed around the EGR with card cleaner during idle looking for a reaction but nothing...

Possibly a damaged piston for the following reason: You show in a previous post a picture of a spark plug with the ground strip pressed into the electrode. I saw this on three different spark plugs on the same engine at various extents and each plug coralated to a chipped piston. The engine had experienced several cycles of severe detonation which chipped three of the six pistons and pushed the chipped pieces into the spark plugs. Initially when the engine ran poorly afterwards I thought the detonation forces some how bent the ground straps on the plugs until not too many miles later perhaps a few 100 the engine started to burn oil. It was turbocharged and digressed to a point where oil could literally be blown out of the valve covers from combustion gases getting past the pistons.

The engine was disassembled revealing the damaged left bank pistons and broken piston rings that had carved a groove into the cylinder wall. You don't need a turbo to damage pistons, detonation alone for any reason can do it especially on the cast 2.8L pistons, the ones I damaged were hypereutectic. It may sound like a stretch but the excessive oil fouling of one plug and excessive emission of poorly burnt fuel suggests there is a serious problem with that cylinder.

I hope I'm wrong, but something likely bent the ground on that plug internally. Maybe someone dropped something in the engine while working on it and didn't want to remove the head to get it thinking it was small enough to pass through. Had a friend drop a carbuerator screw in the intake in an old school Impala and follow through with the above knocking a hole in a piston.

[This message has been edited by Joseph Upson (edited 08-10-2010).]

That right there is my worst fear. Luckily, the compression test in said piston was 120 psi, that leads me to believe that there is nothing absolutely catastrophic but i do fear i have a damaged engine...ill start the bidding at $100 HAHA

quote Originally posted by Williamsr815: That right there is my worst fear. Luckily, the compression test in said piston was 120 psi, that leads me to believe that there is nothing absolutely catastrophic but i do fear i have a damaged engine...ill start the bidding at $100 HAHA

My next suspicion was going to be fuel washing of the cylinder wall ruining the rings in that cylinder. 120 is very low if the others are measuring near or greater than 150.

When i did the test, i didn't bother to test any other cylinders because i had my mindset on the one i thought was dead. In the book i read that anything under 100 is questionable, i guess i should of tested a good cylinder before jumping to conclusions...back to the garage!

quote Originally posted by Williamsr815: When i did the test, i didn't bother to test any other cylinders because i had my mindset on the one i thought was dead. In the book i read that anything under 100 is questionable, i guess i should of tested a good cylinder before jumping to conclusions...back to the garage!

Yes, it has to be a relative test, I recall pressures in the 150 range on a good 2.8L, I believe if you have more than about 10% difference between cylinders depending on the source you are approaching rebuild but by the numbers I measured some time ago 120 is near dead when coupled with the engine symptoms.

Well i tested 2 other random cylinders both read dead on 120 psi, so it is relative. Either i have a totally dead motor that is somehow still running or my gauge is off. any Ideas on the 1500 rpm idle? When i have more time im going to remove the EGR and make the block off gasket just to make sure thats not the culprit.

quote Originally posted by Williamsr815: Well i tested 2 other random cylinders both read dead on 120 psi, so it is relative. Either i have a totally dead motor that is somehow still running or my gauge is off. any Ideas on the 1500 rpm idle? When i have more time im going to remove the EGR and make the block off gasket just to make sure thats not the culprit.

That's a tough one, my initial suspicion would be a vacuum leak. I would also carefully remove the IAC motor and clean the passage and pintle to make sure the idle fluctuation is not caused by difficulty metering idle air. Be careful with it on reinstall, it doesn't mind breaking. You could have a sticking injector fouling up the #2 cylinder and for a quick test you can disable the EGR by simply disconnecting the vacuum line and plugging it. If you can get the extreme rich problem resolved that might result in a big improvement although I still believe 120 is low for the 2.8L. I could be wrong, I've built so many different engines I could be getting the numbers crossed.

Ok, while it was idling i pulled the vacuum line and plugged it, no change. I drove it around and it dropped idle to around 1000 for a while then randomly died at a stoplight. im beggining to think a clogged cat is part of the problem so i hope this cat delete pipe will help. Ill keep you guys posted on how the EGR testing goes tomorrow.

Did you ever check the fuel pressure with a gauge? Do you get the fuel pressure to be up there when it "primes"? Or does it take till you have oil pressure for the fuel pump to run? Have you checked the timing?

Pull the vacuum line off of the fuel pressure regulator and see if there is fuel in it. If there is fuel in the vacuum line, your fuel pressure regulator is leaking fuel into the intake via the line.

[This message has been edited by phonedawgz (edited 08-10-2010).]

I have a fuel pressure tester but i do not have a fitting to attach it to the schrader valve. Isnt there a way to roughly estimate the pressure? I read somewhere that you can prime it a few times, press the relief and gauge the spray.
Tomorrow when im working on the EGR ill check the regulator line to see if there is fuel in it.
Thanks for the help.

Be careful of cracking the EGR to Intake Manifold corrugated metal line when you mess with the EGR valve.

And while you are right there, check to be sure it isn't cracked as that will cause a massive vacuum leak.

http://www.harborfreight.co...tm_source=googlebase

$15.99 Harbor Freight

So new proble, i suspect is a bad heater core, if it sits, vapor starts to come out of the dash and there is coolant dripping on the pass. floor.
I removed the cover and there are puddles of coolant in there. Im trying to dignose whether its a bad core or there is just a loose line or the like, any suggestions?

Also, while under the dash i saw this:

Im assuming the previous owner put this in?
And lets play name that connector!

It looks like the factory speaker connection that was just left there after the amp was installed, correct me if im wrong.

Thanks.

Bad core - replace the rubber hoses also. The 'rot' and start to leak. First indication is condensation on the windsheild and the smell of antifreeze. It is possible to get condensation on the windsheild when running the defrosters with the air on cold with Air Conditioning because the AC runs while on defrost. So condensation on the windsheild isn't always a 100% indicator of a leaking core.

Heater core $42.79 (AC) $44.79 (No AC) + Shipping - Rock auto
http://www.rockauto.com

You had to disconnect the heater hoses from the core right? And those connections are outside the heater box in the front trunk.

Connector - Emergency Flasher and horn relay

--edit
oh the ORANGE connector. IDK - it doesn't exist on my spare '86 GT harness

Amp - no idea

[This message has been edited by phonedawgz (edited 08-12-2010).]

Connector for the factory subwoofer?

i didnt remove the coolant lines because i was just inspecting the core for leaks. My dad is the manager of the local NAPA so he gets me the hook up with parts, new heater core should be home whenever he is.

Cool cool

Nice looking Fiero. You should be having some fun with it. They are fun cars to drive.

So how old is the guy with three cars? Just wondering. Airplane mechanic for real?

Well im 19 and currently in school to get my A&P license.

At the moment, i am stuck with the damn cat welded to the exhaust, not literally, chemically. i got the springs off surprisingly easy, the muffler clamp on the other end broke into pieces the second i hit it with an impact...so there is nothing holding it on but friction, ive soaked it in PB blaster, beat it and tried to twist it...are there any secrets to applying force in just the right area? If not i guess ill just remove the muffler as well and shake all the crap out while im at it...back to the garage.

The cat is usually welded to the exhaust. Normally you will end up cutting the cat off, and then welding the new one on. If it was attached with clamps, the dimpling of the clamps on the pipe will prevent the pipes from coming off. You can again cut it, or you can cut a line with a 4" cut off wheel, along the length of the outside pipe of the two that are slid together, and then with a tire iron pry the slit open expanding the outside pipe so you can remove the inside. IF you need to take it to someone to weld later, make sure you have the entire cat/muffler mocked up on the car, and then install screws through the joints so when your remove the pipes, nothing gets out of place. The welder can take out the screws when he gets the joints welded and weld up the screw hole also. You can also muffler clamp the cat on if you chose

Well that helps knowing they are actually welded...ive been beating on it for the past hour...time for the cut off wheel.