The engine does not idle but with revs (2000 and up) smoothly. After break in the engine worked ok (bad idle, almost stopped at lights) but after ECM reset hasn't idled at all. The timing was set at about 25 btdc to get the engine working (ECM change it to even more maybe 30).

Any ideas what could be the problem?

How much btdc you have with your aftermarket cams, is 25:ish normal at all?

Thanks for advance
BTW the car is -90 camaro

 

is that w/ the EST disconnected so its base timing ? stock setting is at 10 degrees, im not sure what youd have to run w/ that cam, maybe 12ish? if you havent set timing w/ that disconnected, that could very well be your problem.

 

how big of a cam did you go with? after i installed my cam, my car didn't idle very well for a while either. with a little time, the computer adjusted and now it idles fine. i think i show about 27-28* timing with the EST wire plugged in.

 

Thats 25* with EST off, with EST the ecm set the timing over 30*

 

id say back it way off, like to 12 or so and try it around there. 25 degrees advance is waaayyyy too much.

wait, did you mean you have to have it at 25 to get it running or you did that when you started it b/c of the new cam? if its just b/c of the cam, back it off. if you did it because thats the only way it would start, somethings not right. did you replace the timing chain when you did the cam? are you one tooth off on the dist?

 

a tooth on the dist. won't matter cause that's the same as turning it. you can go with more than 12 degrees, too. like he said, if it'll run with less, it'd try less but maybe still 14 or 15 or so. what is the duration on that cam? i tried to look it up but i didn't find the 260H V6 cam.