Originally Posted by
Pulse_GTO
The car is a 2011 CTSV with Lingenfelter heads, Lingenfelter cam, headers, ported snout, ported blower, NW 102mm TB, meth injection. When the car is at operating temperature, the commanded AFR is in the 11's until I start driving it. Is there a table that I am missing? As you can see from the WB data it is rich in the idle area, but once I start driving it, the commanded AFR goed in the 14's and not the WB says I'm in the 15's, so it goes lean. I feel like I'm chasing my tail. The car ran fine before the blower was ported, actually ran fine for about a day, then the idle started going to crap and part throttle started going lean. I went over the car after that, re-did the MAF calibration and got it running fine, but now it's back.
When it first came back I did notice that the timing at idle was around 0, but I was commanding 18. I halved the Idle Overspeed table and had to zero out the Base Idle Aiflow table to keep it from idleling extremely hi. Could it be something mechanical? The max kpa I could get on the dyno was 208-210, but the next night at the track it went to 230kpa. Also we are seeing about 12-14psi at 1/4 throttle around 2000rpm while driving normally.
I'm open to suggestions as I think it may be something other than the tune since it left running great the first and second time.