Delta 88 rough idle + (1988)

This has been very interesting so far. I have reviewed many of the posts and they have helped improve the car, but still having some troubles. Thought I would post my symptoms and see what insight others have.

Things I've tried: Plugs, wires, MAF (was getting code 34, thats gone now). Currently no error codes for 2 days, but problems below persist.

Car runs great until warmed up (about 10 -15 minutes) then:
1. Rough idle and rough accelleration - feels like a cylinder isn't firing. I've replace plugs & wires
2. Again, after its warmed up, I also begin to feel a deep vibration (maybe once every 5 minutes) when under power anywhere between 30 & 55 MPH (if I let up on the gas it goes away for a while). It feels something like a driveshaft problem I had on another car, but its not pulling to the side. I'm afraid its the tranny. Also, this goes away if I shift down from "D" to "2"

Any thoughts are appreciated. Especially, is it possible for these two problems to be related?

Thanks . . . these forums are really great!

I forgot to mention - the gas mileage has gotten drastically worse

Tony,I would check for a vacumm leak from the rubber hoses under the hood especialy the ones toward the front of the intake manifold( hard to find )but very troublesome,did a timing chain once and then found it. BOL

Turned out the problem was caused by the computer. It was telling the injectors to run wide open. But it was only acting up after the temperature of the interior increased.