First start Leans out? - Third Generation F-Body Message Boards

90c350 · 05-28-2009, 01:37 PM

Just wondering if anyone has any tips for me? Im using a 7747ecm with a slightly modded engine and for the last month or 2 when I start it up in the morning it will fire up fine and then after about 4/5sec it will gradually start to lean out and run bad?? I tune with tunerpro and winaldl and I also have an LC-1 Wbo2. Now this only happens in the morning and it doesnt seem to matter what temp it is. The tune is good BLM/INT +-130/125 etc. It was fine during winter, even a little bit rich at cold start but now it will go as lean as 18.1 afr shortly after it starts and is idleing?? Any help would be greatly appreciated!! Thanks

RBob · 05-28-2009, 03:05 PM

Try slowing down the after start enrichment decay. Note that this is also referred to as choke enrichment. Of course you want to do this in the table that corresponds to the start up temperature. Don't change it where it was OK this past Winter.

RBob.

90c350 · 05-28-2009, 11:08 PM

Thanks for the help Rbob once again!!! I got it figured out now. Just need to get moved and unpacked this weekend and I can retune a new chip. Thanks again, Greatly appreciated