The last couple of days I have been getting a real lean start-up weather the engine is warm or cold. The trims a bouncing all over the place and won't stay stable. The afrs bounce from 18.2-20.0, but if I drive slowly down the street within about 100 yards the problem goes away and then the idle is a perfect 14.7.


In the UTEC I have added 90% fuel at idle and the problem is still there. I am also running 780's

Any ideas anyone?

 

Well here it goes.

I just disconnected the front 02 from the main harness and it actually works. The afr is a tad rich (13.6-14.0) but it idles perfectly.

Now the UTEC has closed loop fueling already enabled Im wondering if I don't even need it connected since all of the trims seem pretty normal now granted it could be because of the dis-connected 02.