1990 C4
Idles fine but when I accelerate past 2500 RPM the car bogs down and stalls. It sounds like it is flooding out and i do have a strong emission smell. I replaced gas filter (good fuel pressure). Fuel pump working. Does show signs of catalytic converter problems. I took off the O2 sensor trying to help air flow but still have the stalling problem. The TPS is working fine. New Idle air control.

Any help would be appreciated.

Thanks!

 

was up, sounds like the m.a.f to me, or maybe the throttle position sensor. i'm leaning towards the maf,it sounds like its in "just get me home" mode. check for the code it should pop up.

 

you should drive around with a fuel pressure gauge taped to the windshield and see what happens when it starts cutting out..

 

If you have a vacuum gauge, install it on on a vacuum port for engine vacuum. You should have around 16 - 18 inches of vacuum @ idle. Raise rpm to around 2500 rpms and holdit while watching vacuum gauge. If it doesn't return to aproximately the same reading at idle, then you have an exhaust restriction. I think your assumption about the converter is correct, this is the way to verify it. [8D]

 

where is the MAF sensor on 1990 vette.

 

i just found out that 1990 vette didn't have a MAF it was replaced with a MAP sensor.

I will try the vacuum test and fuel pressure test. Thanks for the advice.

 

I am interested in the results when you're done.

BarryZ
Reading PA

 

Actually, the MAF wasn't "replaced" with the MAP. GM's and most all electronic fuel injected cars have MAP sensors, since fuel calculations are based heavily on the Manifold Air Pressure. Early 90's, GM experimented with speed density in order to do away with MAF sensors, since their first attempt at it was not a huge success. In later years they have come up with a much better sensor for sequentially port fuel injected engines. Sorry for the drawn out explanation. [8D]