first a little back story..

I just installed a 2003 LQ9 out of an escalade into my rock crawler. The motor came from a wrecker on craigslist with harness and computer. I had the stock harness and computer redone by Wayne hartwig. I also converted the intake to drive by cable. I don't think it changes anything but I flipped the intake back wards in the buggy.
I fired the motor and it cranked over instantly, good oil pressure, good throttle response.

now to the problem: on firing the buggy it instantly ran at RPM it also is throwing L and R bank rich codes.

I replaced the intake gasket w/o change
I replaced the idle air controller and it fixed the problem for a few minuets.




any help would be much appreciated..

 

I would say a vacuum leak somewhere, that's where I would start. Even a small small leak and cause a rich condition.

 

what is a normal vacuum reading?