Missing when wearmed up.

[D]

My 91 misses in the 15-2500 rpm range only after 10-15 minutes of driving. It runs perfect when cold. What could this be?

 

[config]

I'd start looking somewhere in the EGR circuit (both mechanical and electronic). Reason being is the EGR only kicks in after the engine is warm. I had a similar on one of my cars (long story).

 

[sink]

Only thing is, the EGR is designed to open at about 1500 or so and higher. An EGR problem would be apparent at RPM below 1500 or so. If EGR fails open, you should see no difference at these revs. If it fails closed, you should see no problem at all.

 

[JT]

I had a problem with my EGR, it was electrical. Causing the EGR to fail. I was noticing when driving around 65mph the truck would begin to sputter like sudden loss of accelleration. Had that fixed, and sparks replaced along with wires...no problems since except my O2 sensor needs to be replaced..arghh!!!!!!!!! If its not one thing its another

 

[sink]

How about that. I guess with comp controlled spark, the computer must be retading timing when its trying to open the EGR to account for the extra leanness. I've got to quit thinking old school.