ok guys i have a bit of a stumper here i have 96 ws6 i just installed pacesetter lts and custom y pipe and 3 inch pipe all the way back, went ahead and did plugs wires and compression test while i was in there anyway the problem is now the car runs strong when cold but as soon as it warms up it starts stumbling bad when under a load ie. in a high gear or at wot. the car never missed before i have checked all vaccum lines done the run in the dark looking for shorts nothing. i installed lt4 km thinking it was pulling time when it got out of closed loop but it didnt help i am thinking it has to be something with the computer and am saving for a dyno tune if anyone has any other ideas and/or knows a reliable affordable place to get a tune in the fortworth area please reply.

thanks guys

 

Sounds like O2 sensor(s). Did you install new ones? Might have damaged during install. Wires might be touching headers.

 

I would think O2's also just due to the fact that you did a header swap and that seems to readily kill O2's while the new headers are going through it's first few heat cycles buring off all the extra gunk.

 

I just did the same install and I have similar problems. Only my car won't idle after it warms up. Is there a way to clean the O2's?

 

I have a similar problem. Mine idles fine, but after it warms up the SES light comes on. I'm sure it's my O2's since my A/F is reading constant rich, which it didn't before.

 

Mine did the same thing, it was a bad O2 ... It was so bad that coming up even small hills, id have to downshift and keep it above 2800ish ? Or it would start bogging and ****.

 

I guess you could unplug your 02 sensors and see if the problem still exists.

 

It sounds like a good idea to use your old o2's for the swap them have new ones handy afterwards? I am about to do my headers and I have the new o2's still in the box. I was going to do them at the same time but it sounds like its best to wait?

 

really the o2s you think i am not getting any codes thrown and i dont think its shorting out anywhere on the wires i crawled under it with it running in the dark no light show. i will try the o2s i guess. keep the ideas coming i am probably going to get a tune too if anyone in the dfw area has a recomendation.

 

Yes.