89 IROC 350/700--mods below

Still trying to figure out rough idle--started basically when car started running REAL rough all the time--barely made it home. Ended up taking it to a shop--they said stock Dist. was trying to destroy itself (was full of rust, etc)--replaced with a rebuilt dist, cap, rotor, coil, maf, and fuel filter. Car would run, but developed a very rough idle-- "If it was a non computer car" I would say it has a low speed miss and surging (rpm varies up and dowm 200/300 RPM) and sometimes dies while idling.

Could something in the rebuilt Dist. (like ignition module or something) be causing this?

Replaced tps and Iac (cleaned everything good) and adjusted to spec per Vader article/post- -still the same. (tps with ignition on --not running .54--it is .52 when running)

Borrowed OTC 4000E scanner and have checked what I know enough about to check--when on a road test with scanner--spk advance is floating from 28 to 31 while idling--will go to 35/36 under light accelaration, but goes back to 25/26 under hard acceleration and will stay there as long as I have my foot in it. Is this normal?

No knock by ear and by knock sensor.

What should initial timing be set at? If initial is off--can it cause a problem like this? What should total timing be at full acceleration?

Help! PLEASE!

 

Its difficult for anyone to tell anyone else what they should be running for timing. THe stock setting should be 6*BTDC. As for total timing, I don't know what the stock setting is, but you will just need to play with it. I just got my new engine running and I am playing with the timing, fuel pressure, and will start burning some proms pretty soon. I see by your sig you have plenty of mods, so the only thing I can suggest is to just make a change, note it or remember it, and test it out. Thats pretty much what I do. Use the scanner, feel the engine, check the plugs.

Good luck...