Ok,

Put on my new timing gears. I lined the notches on the cam and crank so they were pointing at eachother. My car gets gas, spark, and now the cam is turning (thanks to the new gears). It won't even try to start. I'm pretty sure it's a timing issue.

By the way, this car is an 87 4cyl with DIS.

The one thing I'm a bit confused on is the spark plug wires order. I know from my haynes manual the cylinders are numbered from right to left 1,2,3,4 and on the DIS, from bottom to top, numbers on the coils are 4,1,3,2. I hooked up the wires in this order, but it still won't start. I get a backfire every now and then.

Any suggestions/corrections

Dave

You have it a bit backwards with the firing order. It should be: bottom to top 1,4,3,2. Hope that gets you going. Good luck!

Phil

------------------
87 FIERO GT 2.8 5spd

If you found my advice helpful, please take the time to give me a positive rating. Thanks

I thought most 4 cylinder engines were 1-3-4-2 firing order. It is according to my Pontiac service manual, page 6A1-21 for the '87 Fiero.

[This message has been edited by avengador1 (edited 01-22-2004).]

Yep, you exactly right! I was going by the way he stated the bottom to top positioning. Thanks.

Phil

------------------
87 FIERO GT 2.8 5spd

GM auto tech for 27 years. Specializing in electrical and computer problems. Now on workers comp. and it looks like I will be unable to return to work as a tech.

quote Originally posted by GTDude: You have it a bit backwards with the firing order. It should be: bottom to top 1,4,3,2. Hope that gets you going. Good luck! Phil

you're the man Phil
I'll go check it out....maybe tomorrow, temp right now is 4, wind chill is -18
I'll post my outcome from the new wiring tomorrow
thanks
Dave

It still won't start. Here's the deal. I replaced the timing gears in my 87 4cyl DIS....slots on cam and crank are pointing at eachother so it's timed right. Plug wires are now in right order (thanks Phil). I verified I'm getting spark (checked each wire while engine was cranking) and know I'm getting gas to TB (see it spraying in there when cranking). Plugs are gapped properly (0.060).

I crank and crank but nothing but a little pop every couple seconds. I even sprayed starter fluid in the TB but got nothing

any ideas?

Dave

quote Originally posted by ditch: Ok, Put on my new timing gears. I lined the notches on the cam and crank so they were pointing at eachother. My car gets gas, spark, and now the cam is turning (thanks to the new gears). It won't even try to start. I'm pretty sure it's a timing issue. By the way, this car is an 87 4cyl with DIS. The one thing I'm a bit confused on is the spark plug wires order. I know from my haynes manual the cylinders are numbered from right to left 1,2,3,4 and on the DIS, from bottom to top, numbers on the coils are 4,1,3,2. I hooked up the wires in this order, but it still won't start. I get a backfire every now and then. Any suggestions/corrections Dave

Just to make sure... You lined up what? The keyway notches on the crank and cam or the notches/dots on the gear teeth? If you lined up the key notches on the cam and crank then you have to tear it apart again and line up the gear marks. Only the gear marks matter.

Ignore pretty much everything about "normal" timing and firing order on DIS.

Yes... 1234 counting from the right, pulley, side of the car

NO... 1342 is for a distributor motor. DO NOT wire a DIS 2 brick like that!

1 & 4 must be on the Bottom coil.

2 & 3 must be on the Top coil.

It doesn't matter which post on the coil is used. It only matters that each plug pair is on the correct coil. The DIS module will fire the pairs as it needs to.

DIS is CRANK timed! It doens't know or care anything about the CAM. You should be getting a spark no matter how messed up the cam might be.

quote Originally posted by theogre: Just to make sure... You lined up what? The keyway notches on the crank and cam or the notches/dots on the gear teeth? If you lined up the key notches on the cam and crank then you have to tear it apart again and line up the gear marks. Only the gear marks matter. Ignore pretty much everything about "normal" timing and firing order on DIS. Yes... 1234 counting from the right, pulley, side of the car NO... 1342 is for a distributor motor. DO NOT wire a DIS 2 brick like that! 1 & 4 must be on the Bottom coil. 2 & 3 must be on the Top coil. It doesn't matter which post on the coil is used. It only matters that each plug pair is on the correct coil. The DIS module will fire the pairs as it needs to. DIS is CRANK timed! It doens't know or care anything about the CAM. You should be getting a spark no matter how messed up the cam might be.

Hey Ogre,

I lined up the key notches on the cam/crank. Guess I'll have to tear it down again and correct this. No big deal now that I know what I'm doing.

I know it sounds crazy, but I'm kind of glad this is the problem. At least I know how to correct it.

One thing. I didn't see any marks on the gears that I bought. Where should the marks be?

thanks
Dave

Dave,
I just happened to have a set in the garage. Here is a picture of the dots and alignment.

If these were new gears they would be cleaner and should be easier to see. Good luck with it.

Dwayne

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[This message has been edited by 1MohrFiero (edited 01-25-2004).]

I had a feeling from the way you said above that may be what happened. Oh Well.

quote Originally posted by 1MohrFiero: Dave, I just happened to have a set in the garage. Here is a picture of the dots and alignment. If these were new gears they would be cleaner and should be easier to see. Good luck with it. Dwayne

cool,
I'm going to fix the problem tomorrow as long as the snow lets up (I'm working outside). I hope my new gear set has marks...I don't remember seeing any on them. I'll post what I find.

thanks everyone

Ok,
My marks are lined up properly this time. I'm getting spark and fuel. The darn thing still won't fire. It's sounds like it's trying, but no go. I shot some starter fluid in the TB and still no go. Any ideas on what I should check next?
Dave

Take the plugs out. You may have fouled or drenched them. That could kill the spark on the plug until they are clean/dry.

If the engine backfired... check all the vacuum hoses. Don't forget to check both ends of the brake booster line and PCV valve line to the manifold. Backfire can blow those lines off or even rupture them.

Depending on how bad it backfired, you could also have burned the MAT sensor. I'm not sure if that would keep it from starting by itself but it won't help anything.

recheck ALL the engine bay wiring again. It is really easy to overlook something important.

How long has your fiero been down? I had the same problem once and later found out that the gas was old. I sucked out the old gas, put in new gas and it started right up.

It's been down a couple months. I'm going to check the plugs as Ogre said and see what they look like. I did quite a bit of cranking prior to fixing the timing gears and know that they were pretty soaked with gas after that (I checked them before doing the gears).

I'm thinking the gas is probably ok since the car didn't even try to start when I loaded the TB up with starter fluid...it should definitely try with that stuff.

One thought I had...since the cam gear was stripped real good. Could it be possible that the cam is damaged or broken?

Bear with me...I'm far from a good mechanic and have much to learn about engines

thanks for the good ideas
Dave

The 88 Fiero factory shop manual says in the specs for 2.5 firing order is 1,3,4,2. The cylinder order is 1,2,3,4 starting at the front of the engine (the front of the engine is the end where you put your timing gears in). Looking at the DIS as it is mounted to the block, UPPER coil TOP terminal is 2, UPPER coil BOTTOM terminal is 3. LOWER coil TOP terminal is 4, LOWER coil BOTTOM terminal is 1. Ogre may have it right with the fouled plugs, if that doesn't help...Do you know if this engine was revving along happily or at idle when the gear crapped out? I dont think the 2.5 is an interference motor, but maybe its time to start looking for bent valves / compression?

------------------
Tim
Red 88 Formula Auto
Stock 2.8 100K+ Miles
Hypertech Thermomaster
NoCat NoEGR

[This message has been edited by FrugalFiero (edited 01-26-2004).]

quote Originally posted by FrugalFiero: The 88 Fiero factory shop manual says in the specs for 2.5 firing order is 1,3,4,2. The cylinder order is 1,2,3,4 starting at the front of the engine (the front of the engine is the end where you put your timing gears in). Looking at the DIS as it is mounted to the block, UPPER coil TOP terminal is 2, UPPER coil BOTTOM terminal is 3. LOWER coil TOP terminal is 4, LOWER coil BOTTOM terminal is 1. Ogre may have it right with the fouled plugs, if that doesn't help...Do you know if this engine was revving along happily or at idle when the gear crapped out? I dont think the 2.5 is an interference motor, but maybe its time to start looking for bent valves / compression?

Yeah, I have my plug wires in the order you described. I hope cleaning up the plugs helps. I don't know when the gear stripped. She just told me it quit running one day.
Compression check is definitely a good idea though. I'll have to get a guage first.

This job has been pretty cool in one way...I now own tools I've never had: Craftsman gear puller and Craftsman tap/die set. I'm glad i have them though. The tap/die set is really cool....I should have had one of those a long time ago.

Dave

quote Originally posted by ditch: This job has been pretty cool in one way

If you are working outside in Indiana all your new tools have been really cool....Brrrrr!

------------------
Tim
Red 88 Formula Auto
Stock 2.8 100K+ Miles
Hypertech Thermomaster
NoCat NoEGR

I was thinking about the same possibility of them being install wrong the first time. I never worked on a 4, but the pistons may have bent valves. If you checked the plugs and gas, run a compression test on the cylinders to be sure valves are OK. IF you get no or low compression, prob gonna have to pull the head.

quote Originally posted by 1MohrFiero:

Warning! Stupid question ahead:

Dave; Did you make sure that those two little dots were properly lined up AFTER you stuck the gears in there (did you make sure that after you re-installed the gears, the two dots were directly looking at each other?) The gear dots should be as in the picture above after you re-installed the gears

Ed

[This message has been edited by ED's85GT (edited 01-27-2004).]

quote Originally posted by ED's85GT: Warning! Stupid question ahead: Dave; Did you make sure that those two little dots were properly lined up AFTER you stuck the gears in there (did you make sure that after you re-installed the gears, the two dots were directly looking at each other?) The gear dots should be as in the picture above after you re-installed the gears Ed

Ed,
No question is too stupid when it comes to me....I'm definitely learning as I go here...I'm no mechanic. I did have them pointing at eachother. The smaller gear had an arrow on one tooth and the large gear had an indentation. Both points were pointing at eachother perfectly.

We've had a bunch of snow here in the last 2 days so I'm not touching it for now

I'm going to check the plugs and do a compression test while each is out and will post results here...thanks for all the help so far

I'm going to do whatever I have to do in order to get this car running again...that includes bugging PFF members for advice You guys are a wealth of info.

Dave

Again... The "firing order" in the traditional sense Does Not matter...

DIS WILL NOT work right if you treat it like a distributor. You will likely cause a major backfire and could damage parts.

Connect the plugs to the DIS brick as I listed above. The module will fire the pair of plugs at the correct time and manage the actual firing order.

Yes, one tooth off could be enough. That is a fairly big error in timing.

Instead of spraying starting fluid... try pouring a little FRESH gas in the throttle. Thats how I found out my old gas was the problem.

at this point, I would do the following..

4 new plugs (don't bother even looking at them. toss the old ones, replace with new. generic cheapies (autolite, etc) work just fine, avoid most of the platinum tip stuff (DIS eats that for lunch in a few miles).

put as much fresh gas in the tank as possible, or (preferrably) drain and replace it.

make sure the tach indicates some rpm when cranking

if it still isn't starting........

pull the valve cover and check out the valvetrain. bring the motor to TDC #1 and make sure both rockers on #1 are not lifted at all, then turn motor over (in correct rotation) and make sure that after around 150-180* of rotation, the exhaust valve starts to open. this will absolutely verify the cam is timed right to the crank, AND that the cam is ok, AND that all your valvetrain is workin.

check fuel pressure. maybe it's enough to spray fuel but not enough to get the right mixture.

ogre is dead on about the DIS coils. an easy way to remember - First and Last go on Bottom (1 and 4 on bottom coil) - FLB. Friendly Little Bugger for the PG13 version of that one

You might try squirting a tiny bit of oil into each cylinder when the plugs are out. seems some people have success with that to help build compression on worn rings (or walls that have been fuel-washed by lots of cranking with no start?) you can also leave the plugs out for a few hours to let any accumulated fuel evaporate out.

[This message has been edited by nick2x88 (edited 01-29-2004).]

sounds like good advice,

I'm going to wait on this car for a while. The high temperature tomorrow is supposed to be 7 degrees and the lows have been in the negatives. Wind chills have been in the negative teens. All the work I'm doing on this car is outside. It wasn't a big deal when it was in the 20-30 degree range, but now it's a bit cold to be playing with it...I've got 2 others that run just fine so I'm in no hurry.

My plan of attack is as follows:

1) I put on new AC Delco plugs when I got the car, so I'm just going to take them out and clean them off.
2) I'll check the timing visually with the valve cover off as stated above....good idea. It needs a new valve cover gasket anyway.
3) If the timing is correct, I'll do a compression check of all cylinders and go from there.
4) If compression check shows a BIG problem in compression, I guess my next step will be to pull the head and see about bent valves

It may be a few weeks, but I'll post my results here when I get back on it.

thanks again everyone....I know I've said it 10 times, but I couldn't do this without all your help

Dave

this car is going to live again whether it likes it or not

Well, bad news
I checked compression in all cylinders...here's the results (with a shot of oil in each cylinder also). The car is sitting in 30 degree weather by the way.

#1 = 70psi
#2 = 70psi
#3 = 50psi
#4 = 90psi

Looks like it may be bent valves as suggested above. I crank it and it really wants to start...almost does, but just won't pick up the beat.

Anyone else agree with this? Ideas?

thanks
Dave

quote Originally posted by FrugalFiero: I dont think the 2.5 is an interference motor,

I don't think that it is either, but i could be wrong. Anybody know for sure? I have a feeling that your
problem isn't bent valves, because if it were, when the valves stuck open you would have zero
(or close to it) compression from one, or more cylinders.

Disconnect power to coil pack (pull plug wires too for safety) (leave plugs in) put your ear as close to the T/B as you can while someone cranks the motor over for you, then listen/feel for blowback thru the T/B. If you are getting air blowing out from the T/B you may have bent valves.

I saw a guy use cigarrette smoke to check for bent valves, if it sucks the smoke into the motor valves are ok
but if it blows it out of the carb/tb the valves are bent.

Ed

quote Originally posted by ditch: Well, bad news I checked compression in all cylinders...here's the results (with a shot of oil in each cylinder also). The car is sitting in 30 degree weather by the way. #1 = 70psi #2 = 70psi #3 = 50psi #4 = 90psi

Did this motor run ok before you replaced the timing gears? None of those compression readings sound too spiffy. If it has lotsa miles on it you may have more work to do.

------------------
Tim
Red 88 Formula Auto 2.8 100K+ Miles - Hypertech - No Cat -No EGR

Murphys Law - "Nothing is as easy as it looks, Everything takes longer than you expect, And if anything can go wrong - it will, At the worst possible moment!

Assuming the motor ran ok before it stuffed a gear...

That sounds like:

You still have the cam a tooth or two off.
You did the test wrong. (Must have TBI locked full open.)
You have exhaust blockage.

Any/all of those will keep it from breathing right and screw up compression testing. Cold, especially cold dry, air in a cold motor will also lower compression some but not that much. You did what is called a wet test (assuming the oil was able to run into the rings good in this weather) which would probably have kept compression around normal.

The cast iron 2.5 is NOT an interference engine. Plenty of people on and off these forums have stuffed the gears with no valve damage. (The car linked to my cave article for example.) If you managed to bend valves on this engine you have something really major wrong or you have some sort of non stock pistons with reduced clearance.

Bent/burnt valves don't automatically mean no comrpression. Depends how bad the problem is.

------------------
Edison Carter: When did the News become Entertainment?
Murray: Since it was invented.

The Ogre's Fiero Cave (It's also at the top of every forum page...)

quote Originally posted by FrugalFiero: Did this motor run ok before you replaced the timing gears? None of those compression readings sound too spiffy. If it has lotsa miles on it you may have more work to do.

this car has 86000 miles. I bought it from a woman who said it stopped running one day. I found out it was the timing gears (the nylon cam gear was stripped half the way around). I replaced the gears and the marks are lined up (marks on each gear, cam gear has a small hole on it's tooth and crank gear tooth has an arrow).

As suggested above, I'm going to check the timing manually....I'm going to pull the valve cover tomorrow and bring #1 cylinder to TDC. I'll then rotate the crank and see if the exhaust valve opens at approximately 150 to 180 degrees

Ogre...I've eliminated exhaust blockage as a problem.... I disconnected the exhaust before the cat just in case, so it's straight exhaust. I also have the marks on each gear lined up perfectly.

These compression readings suggest something isn't right....likely timing. I'm glad to hear it's not an interference engine....makes it less likely to have bent valves. I don't know the history of this car. All I know is (from info on title) it was purchased from a dealer by this lady in August 2003, and I bought it in January 2004 at 86000miles with stripped timing gears.

Again, my next step will be to pull the valve cover and observe the rockers....also check timing on #1 cylinder visually

thanks everyone
Dave

I'm going to get this thing running without having to take it to a shop!!

Let me start by saying I don't know much about the coil pack instead of a distributor. Since it is common to get the Dist. off by 180 degrees with the timing gear dots aligned, wouldn't it be likely that the cam is off 180 degrees from the crank trigger? Since the crank turns once for the half turn on the cam, your crank trigger won't know that thew cam's a half a turn off.

But if you think about it, since the cam turns at half the speed of the crank the cam will be 180° out every other crank turn. That's why it's important to not mix up the firing order on the DIS coils. The ECM fires two plugs with one coil in a push-pull arrangment. That means that on one plug the spark is going from the electrode to the tip and on the other plug in the pair the spark is going from the tip to the electrode. One plug will be firing on the exhaust stroke of its cylinder and the other plug will be firing on TDC of its cylinder. That's why it's called "waste spark" if you've ever heard that term before, and it's also why the Bosche Platinum plugs don't seem to work well in DIS Fieros.

JazzMan

quote Originally posted by ditch: Ok, My marks are lined up properly this time. I'm getting spark and fuel. The darn thing still won't fire. It's sounds like it's trying, but no go. I shot some starter fluid in the TB and still no go. Any ideas on what I should check next? Dave

Verify that both coil paks are still working. This sounds like a bad one to me.

quote Originally posted by Indiana_resto_guy: Verify that both coil paks are still working. This sounds like a bad one to me.

That's definitely a good point. I did that one already. I've checked spark from each terminal several times and it's always strong as can be.

I'm not too worried about the low compression readings. This motor is sitting in the cold at below freezing and it's been cranked over several times. I'm sure the excess gas has washed the cylinder walls pretty good.

I'm going to verify timing tomorrow...if it's not too cold

thanks
Dave

Man it was breezy today...making it really cold to work on the darn thing. I was going to remove the valve cover, but the EGR valve is in the way. No problem, just remove the EGR valve. Problem was I can't fit a 10mm socked on the bolts because the darn thing is in the way. And of course I don't have a 10mm wrench.

I didn't feel like going to buy a wrench, so I just played with the car a bit. Here's something interresting I found concerning the gas....

It wasn't trying too hard to start when I was cranking it before. I filled up my gas can and added some to the tank...it took 3 gallons to fill it, so it must have had around 9 gallons in there. After doing this, it sounded like it was trying to start better than before. I then unplugged the fuel injector and my friend cranked it while I squirted in fresh gas from a squirt bottle....it ALMOST started....so close. It really wanted to this time. I think it would have started, but it was hard to regulate the amount of gas from my squirt bottle. I was probably flooding it a bit. BTW....when the injector is plugged in it squirts plenty of gas into the TB.

Based on this, I think at least one of my problems is bad gas. I'm going to drain the tank when I can and fill it up with fresh gas.

I checked compression again...after squirting a bit of oil in each cylinder.

#1= 120psi
#2= 70psi
#3= 90psi
#4= 120psi

I don't know why these values are so much different that before. At least they're better

Dave

quote [B Based on this, I think at least one of my problems is bad gas. I'm going to drain the tank when I can and fill it up with fresh gas. I checked compression again...after squirting a bit of oil in each cylinder. #1= 120psi #2= 70psi #3= 90psi #4= 120psi I don't know why these values are so much different that before. At least they're better

Darnit, when I asked if this motor ran good before it ground up the timing gears I forgot to ask if it sat around awhile before you bought it! If fresh gas fixes this problem shame on me for not bringing that up! I have been burned a few times by bad/old gas in snowblowers and lawnmowers - you can pull on the cord till your arm falls off and they putt putt but wont start! It may have been a little warmer (except for windchill) which as theogre mentioned may have an effect on compression. The second readings you took are alot better.

------------------
Tim
Red 88 Formula Auto 2.8 100K+ Miles - Hypertech - No Cat - No EGR

Murphys Law - "Nothing is as easy as it looks, Everything takes longer than you expect, And if anything can go wrong - it will, At the worst possible moment!"

It runs!!!

I drained the tank and filled it with new gas, squirt some oil in the cylinders, and it fired right up. Car runs GREAT.

Not bad. Bought the car for $300, spent around $50 on timing gear set, and $40 on new coils...that's all, and now I have an 87 with only 86500 miles on it. Not a bad feeling for the amt. of money I put in it

Thanks to everyone for the help! + for everyone. You have all saved me a ton of money by helping me to do it myself.

Now I'll be keeping my eye out for another one...number 4.

Dave

quote Originally posted by ditch: It runs!!! Car runs GREAT. Dave

Congratulations!!!! I knew you would get it

Ed

quote Originally posted by ED's85GT: Congratulations!!!! I knew you would get it Ed

thanks Ed,
It's a good feeling having it running...considering all the other possible problems it appeared to have.
Dave

quote Originally posted by ditch: I checked compression again...after squirting a bit of oil in each cylinder. #1= 120psi #2= 70psi #3= 90psi #4= 120psi

Just an FYI. I checked compression again...this time on a warm motor (now that it runs) :

#1= 135psi
#2= 135psi
#3= 145psi
#4= 135psi

can't beat those numbers

Dave