89 2.8 stumbles when warm

I have an 89 Camaro that runs well cold but when it reaches 180 degrees it begins to flutter and miss under acceleration. If I let up it smoothes out a little. I get no codes and the scanner doesn't pick up any abnormalities that I can see. Any Ideas?
Thanks,
Darrin:banghead:

Check fuel pressure. You can rent a gauge at autozone if you don't have one of your own.

If your fuel pump is on its way out, it will present lower pressure when warm.

Fuel Pressure was fine. Checked the timing. Factory setting is 10 degrees btdc. It was set at 2 degrees atdc. I adjusted it and in runs fine. The knucklehead who worked on this before had to have played with the timing. There is no reason to adjust factory settings. If you feel the need to adjust...replace the timing chain.:sarcasmsign: