Gangly

96 LT1 with heads, cam, intake, and BBK 58mm TB. Never had an issue, never had to drill anything out, and never had a tune. No idle issue and codes thrown as a result of it being installed.

smitty2919

You did all that and no tune? Yikes


TB is working fine. The OS on my PCM is a little screwy. The car can and will idle normal. No modifications needed.

BALLSS

so you have a H/C w 58mm TB motor and stock tune?

If so, hope others do not do this

H/C aside...any larger than stock TB used with a A4 car and not tuned for the larger TB will lead to tranny failure sooner than later

smitty2919

Getting back to the tuner this week as he thinks he found the issue between the OS and the idle. His suspicion is that the 02 Tahoe OS is more sensitive to TPS voltage and that the TPS needs to be slotted/adjusted. Should be an easy fix if that's the case.

To be continued.

BALLSS

yeah the "slot" the TPS holes to clock the TPS so you get correct VDC with throttle closed if you opened the blades to get it to idle right method has been done. Not doing so will screw up TPS VDC readings to PCM thus line pressure and shifting are affected on A4 cars....

Rob94hawk

iTrader: (1)

Well ****. Now I have to check my BBK.

smitty2919

With a little tuning adjustment and slotting the TPS sensor, all is well now. Idles great at 8-900 rpm.