94 sho surge problem, very specific

[rick-powell@sbc]

hello, newb to this forum. anyway, ive worked on these cars in the past, but im clueless on this one

94 atx no check engine light, no codes

1. starts great hot or cold

2. revs up to 4k smooth in nuetral

3. also smooth in reverse, even floored it and hit about 35mph

4. in drive it surges, from take off all the way. however with light force it will accel fine, anything over 1/4 throttle will cause a surge like a rev limiter


anyone have an idea

 

[luigisho]

Pull some codes and see what shows up.

Also, unplug the MAF and see if it runs any better.

After that I would conside the throttle position sensor. You can check it for voltage. Should be some info on the forum on this.

 

[93rev2sev]

That it's fine in reverse makes me think it's the VSS.

The quickest thing to eliminate, though, is the MAF. Like luigi said, unplug it and see if it's smoother. If it is, then it needs to be cleaned or replaced.

 

[shobote]

and if you have never cleaned the MAF filament, best to do it anyway; just a couple of bucks worth of electronics or MAF cleaner and 15 minutes labor.
Common symptom for those running K & N or other oiled air filters too.