What is code 20, not in manual
#5
A year and engine would be helpful. The cylinder balance test only works on sequential EFI ECU's so a stock batch fired truck would not have a built in cylinder balance test. At any rate, this is after the normal test routine is finished, and you have to stab the throttle to make it enter the test. I doubt that the autozone guy did all that, but I could be wrong. I would try to pull the codes again.
#6
its an 87 with a fi302 , on my other post some said that the tfi might be going bad , because the truck only acts up after it gets hot. I have replaced the egr, and the evp, the evp fixed the code 33, so im returning the egr today. The truck feels like it misses but only after it gets hot, and only while in drive. the plugs are good, but not sure about wires. Im going to replace the rotor has a little burn on it.