Car sputtering, tried lots of things to no avail!

[Super Phil]

Alright boys....I've fooled around long enough. Now I need some serious tech help.

My car sort of hesitates and sputters intermittently while accelerating. It may run good for a couple of minutes, but then it starts sputtering again. I can drive it around, but it is very annoying when the car is jerking and hesitating.

What I have done to try and fix this is:
New plugs and wires
New coil pack
Cat is gutted
Adjusted cam sensor
Ran injector cleaner (Techron) through
Found and fixed a couple of vacuum leaks
Replaced fuel filter
Fuel pressure is ok

What could my problem be? I read it may be a collapsed muffler, but is it possible to tell without pulling the muffler off? There is no visible damage to the outside of the muffler, so could it still be collapsed?

Oh yeah....the car is an 87...mainly stock...just has a Walbro fuel pump, AFPR, and a Super Phil intake.

Any other ideas? I'm really stumped....and aggravated by this!

Phil

 

[EFFNQWKWE4]

Is the sputter occurring when you're under boost? If so, you could have holes/cuts in the hoses that connect your turbo/intercooler/up pipe.

 

[turbo buicks]

did you also check the ignition module under the coil pack?

 

[Super Phil]

Hi,

The problem occurs under boosted and non-boosted driving. So I don't think it's related to the turbo.

I don't think I checked the ignition module. I just replaced the coil pack and went on my way. What am I looking for/how do I check that?

Thanks!

Phil

 

[turbo buicks]

dot think you can test it directly. but you can get a Caspers coil pack tester (buy or borrow one) and test your ignition. if a spark is weak then you know its the module b/c you got a new coil. also check the MF GPS w/a scantool and try the tap test on it. also know that running injector cleaner through really bad injectors wont help. its mainly for small clogs and carbon and stuff, not meant to replace a 15 yr old injectors. i would check the injectors also. if they are bad and you have plans for the car to get faster than you can step up to a larger injectors. i recommend 50# injectors. they will take you into the 10s and you wont have to ahve the ECM modified for a low impedance injector.

 

[FRANKIEz28]

MAF

Well nobody said it so I will. Try the MAF.
When mine went south it gave no codes and passed the tap test.
Try another good MAF.

Good Luck
FRANKIEz

 

[sackracing]

buy one of those 30 dollar ignition modules from john dicarlo, its worth 30 bucks to have one to test with.

 

[turbosam6]

Before throwing $$$ and parts at it, get a scan tool and maybe a fuel pressure gauge. Puting any parts on at this point is just guessing. Look at the plugs also, and like said above, an ignition tester from Caspers is a good idea.