charles1357

I have a 1989 C4 that I bought about 3 months ago (iowa winter) and have been working on it in my garage. I've driven it about 100 miles on and off in between repairs and its ran great. However, the other night I get in and while backing out of the drive it surges and the Service Engine Soon light comes on, the Instant Fuel Rate quits working and the One to Four shows up on the dash. It went from idling around 600 to 1200 and ran a little rough. The next day I took it on the highway and after about 5 minutes it surged again and all 3 went away and started to run great again and ran great the rest of the trip home. Today I get in it and start it up and there are all 3 again. This time after about 15 minutes of driving/running the idle goes down to 600 while running rough but the One to Four goes off and the Instant Fuel Rate starts to work again but the Service Engine Soon light stays on and is still running rough. Here is what I've done mechanically since I bought it: new rotors, pads, shocks, tires, plugs, distributor pack, plugs, oil change, trans fluid/filter change, air filter, tensioner, serpentine belt, intake gasket. I cleaned the MAF sensor.
All of this has happened in the beginning, middle and end of all of these repairs so I don't think it's anything that I've done BUT...
I also hooked my code reader up but it won't read the car.
I NEED HELP PLEASE!