car stuters under slow acceleration......any ideas?

[z24 turbo 93]

i just bought a 90 tgp and i put new plugs and wires on it. But when i drive it, it stuters a little until you get over 30 mph. It used to be really bad until i replaced the fuel filter and now it is a slight stuter and is driveable. Any ideas on what is wrong. Is it the coils or injector( i am thinking) I also changed the oxygen sensor so that shouldn't be a problem. Also when i accelerate hard it pulls good up to 65 and then the power like shuts off on me? any ideas on that?

[eclipse5302]

Have you checked your fuel pressure?

 

What about spark?

To check for a miss/spark problem that isn't too noticable at idle, hook up a timing light to each plug wire one at a time. Hit the trigger and watch the spark pattern. It should be consistent and smooth at idle and as you increase throttle. If any one of the plug wires shows an erattic or un-even spark light, that plug/wire/coil is bad. Coils and modules go bad ALL THE TIME with these engines (well, actually all GM 2.8/3.1 v-6s).

 

Jason

[z24 turbo 93]

I just put new plugs and wires in the car so those are fine, the coils on the car look good, no rust spots on them. But it still could be a coil. I might take the plentum off and check the injectors someday. The modules for 3.1's are expensive aren't they? And maybe the power shut off is because i am running it hard in OD? Just an idea?

[gpse3200]

Either the coils or the modual. You should got to a junk yard and get a modual with coils from the latest model car you can. Anything form a 3100 or 3400 would be good, all you'll have to do is transfer the backing plate. Definately does sound like ignition.....

[z24 turbo 93]

After driving the car for 2 days now i have some new info. Maybe this iradicates the bad module. When i first start it up it seems to stuter and miss a lot more than when it is warm. Could that still be a bad module? If it is i will go to the junk yard and get a different one and see what that does.

[STR]

After driving the car for 2 days now i have some new info. Maybe this iradicates the bad module. When i first start it up it seems to stuter and miss a lot more than when it is warm. Could that still be a bad module? If it is i will go to the junk yard and get a different one and see what that does.

I have the same problem when its cold, goes away when the car warms up though.

[z24 turbo 93]

Yep, when the engine is cold it stuters a little and then when it gets warm it doesn't do it as much but still stuters a little. But i as long as it makes the winter i will be fine. Also when i floor it it goes up to like 40 now and then wants to shift but it won't, until i let off of the gas a little. My dad is a mechanic and he said maybe it is the fuel pump going bad from what i explained to him. Any one have the same problem. And if you did was it the fuel pump or is the tranny going to hell in it?

[Whiskey River]

My previous car used to have a similar problem. It would stutter until the motor hit about 1800 rpms and then it would take off. Turned out that oil had gotten into my O2 sensor connector and shorted it out. I replaced 3 o2 sensors before cleaning the connector and it never stuttered again. O2 sensors are pretty cheap, try that.

[GPRACER]

any lights on in the dash? service engine soon? bad sensors should set codes.

[z24 turbo 93]

Yeah the check gauges light is on but i heard that is no big deal. I had a tech 1 computer on it and there are no codes in it. My fuel pump is bad i am changing that so that could be most of the problem. But if it isn't that it isn't getting fixed! Thanks for all of the info tho.