For the last 2 years Ive slowly been trying to diagnose the problem of my car...Custom chip was even made for me and nodda. TPS is set to stock and IAC is clean.

Ive done so much to the car it could be anything.

here is a video of my problem when accelerating:

http://media.putfile.com/guess-the-p...-with-the-iroc
Might take a while to load!

This is me turning a corner and nailing it to 45mph or so.

Important Mods:
Holley Stealthram, AFR heads with comp cams goodies, LT4 Hotcam, MSD digital 6 ignition, new walbro fuel pump, SVO 24 injectors, Aeromotive fuel pressure regulator...basically everything has been changed except my bottom end.

Absolutely ANY input would be helpful to me, the car actually ran better in 2001 when it was STOCK than it does now!

Steve

 

http://www.youtube.com/watch?v=pTa6LO00C0s

here is a youtube version

 

im slightly confused, is your problem your tach?

I watched the vid and all i saw was a bouncy tach i couldnt tell itf the motor was acting up too, If your motor is checking out ok and not buggin out like the needle on your tach was id say try a different cluster, it may just be acting up

How is the motor behaving? a little more info on the syptoms would help out a great deal here

 

that is not my tachometer acting up, its my engine.

I dont need to elaborate on the video, watch the tach and listen to my engine.

It is all over the place. Like I said it sputters when I nail the gas

 

sorry the crap sound quality threw me off,
Maybe you do need to elaborate because a video isnt a be all end all of trying to get people to help, what else is it doing, how does it drive under other conditions etc

also are you sure your mods are working right> just cuz its new doesnt mean its good, other members have had issues with the walboro pumps, apparently the quality has gone to crap on those

 

Easy..The sound quality of the video is audible enough to hear the sputtering.

1) Hard to start.
Takes several turns before starting, when it does start the idle will drop and it will stall...basically I have to feather the gas for approx 5 minutes, and then the idle will kick in and go to a little under 1G and sit nicely. If the car is warm it starts immediately and idles fine. A few times I noticed if it idled long enough (15 minutes are so) there would be times where it sounded like it was going to stall again. TPS is set to correct voltage, IAC is clean, MAF is newer.

2) Sputters sporadically when revved while driving. When in Park and revved it sounds decent. In the video I smash the gas and the engine literally just sputters at no matter what RPM its at! RPMs slowly increase but it still sputters all over the place. The car just feels like its being robbed of all power.

When going slowly though subdivisions its ok, but even at slow speeds it sometimes will sputter if too much gas is given from a rolling stop.

3) Random power loss when driving (this hasn't happened since last summer, but then again this summer I have not taken the car out for a 30 minute drive like I did then, ive been too afraid to stall it in the middle of traffic).

The car would run like crap as usual, then 30 minutes into driving would randomly start choking, sputtering, then straight up stall. I would be terrified to stop at a street light or stop sign because it seemed at low RPM it just was going to die. Weird thing about this happening was the car would refuse to even engage the starter unless you let it sit for 20 minutes. Then the starter would get power. I thought maybe the starter was getting heat soaked so I changed that and now the starter engages every time it stalls, however the car still doesn't actually run at that point..the starter just cranks. Let it sit for 20 minutes and it will run for a few..process repeats over and over.

Oil pressure is always good

Im really not sure what else to say, thats what is going on with it.

I put that fuel pump in 3 years ago and have probably put 750 miles on the car of cruising slowly since.

Alot of mods are done to the car like ignition and everything was changed over basically at once. I even redid the top end over again last year to make sure I wasnt screwing something up.

If anyone has any info or would like me to answer a question about part of the car, let me know.

 

starting it cold.
http://www.youtube.com/watch?v=TBxMXidL8LA

after its warm
http://www.youtube.com/watch?v=PY8ySyoa11E

 

bump.

 

Have your ignition module checked.

 

i had similar problems with another car (not 3rd gen...) but it always turned out to be ignition problems which caused it...

 

Some people @IROCzone also mentioned mayb eit was ignition/module related...Ill have to play with it today

 

Yeah as I told you on IZ I had a similar problem with my MSD dizzy change, got the ignition module and pickup changed and it solved the problem..
So check those out. I think Autozone can test them..

 

hey so what happened? was it the ignition?

 

I dunno...it almost seems like a fuel delivery problem.How long ago has the fuel filter/strainer been changed? It seems to be running like a car with a worn out 2 bbl..Also check the intake manifold gasket for leaks.Just a shot!

 

wasnt the ignition....cars been at a speed shop for 2 weeks being looked at by several mechanics.

car will not hold fuel pressure whatsoever. Crank all the way up on the afpr and it goes to 45 and drops to 30 within a minute.

 

Have you checked your injectors. Even if they are new they can be bad...
I would check the injectors. take em out and flowtest them in a rig to see if they holding ....

Jon at Fuelinjectorconnection can helo you with testing of the injectors.
either its FPR leaking back, or injectors leaking into cylinders.

 

sounds like a bad fuel pump acting up. The reason i say this i had the same problem. erractic start and if i gave it acceleration sounds like it was going to dye and then get power then stall and get power continuesouly. have them chk the fuel pump.
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It also could be did u switch ur distributor wires around by chance or. what it sounds like is that ur dist is like 180 off just trying to depict what they could cause. hmm.... hope that helps.

 

if anyone was interested...

1) "idler control motor" - no good (IAC valve?) $78
2) mass air flow has baffles removed and is making car run bad $169
3) fuel pump is not delivering enough pressure $116 for "carter oem?"

$870 to fix the car with labor.

Heres the deal though, that dang fuel pump is a $150 brand new walboro unit I installed last summer, the MAF is new but I took out the screens, and the idler control motor I have no idea what the hell is, unless hes talking about the IAC valve.

I was at work when my dad went to the shop and checked on the progress...So Ill get info in person tomorrow

they claimed with a different maf on it they had laying around, the car ran like a rocket untill it would fuel lose pressure and die.

 

89Kicker

1) idler control motor is the same as IAC
2) Mass air flow meter assemblies can be temperamental when baffles removed - your ECM was calibrated for a stock flow rate. Removing baffles improved the air flow but ECM was not told about the change.

3) Fuel pumps can and do go out all the time (Walbaro could have been a Chinese fake copy - there are many out there.)

//RF

 

that freaking sucks. well at least you have it working right?

 

Yeah I had it fixed...

Turns out the fuel filter wore out my new pump..both were replaced and now all is fine.

http://www.youtube.com/watch?v=dePlthkZtPU

 

At least good info for everyone that comes to this problem.