Idle problems after 4l80e install
Idle problems after 4l80e install I finally got around to finishing up my trans swap. Got the DS and wiring harness in Friday and fired it up. The idle immediately went to 2000 rpm, and the speedo will read 35-40mph with it just sitting there in park. I can put it in gear and the idle will be back to 950rpm or so. I didnt mess with the intake or anyhting etc. I unbolted the headers so the motor would tilt back & took the red connector on the PCM apart to add the new wires for the VSS but thats it up front. Ive double checked everything, the TPS, the small vacuum line on the back of the intake, the TB blade, the temp sensor, the RAF table in HPtuners, installed my old OS that orginally was in the car. Ive tried it all. One thing that has me wondering it, I ran across a post on here somewhere saying that the wiring harness from speartech for the 2nd speed sensor is suppose to go on the front sensor. Well mines on the rear sensor. Could this be realted to my idle problem in any way? Im going to try swapping them when i can get back to my shop tommorow to see if that makes a difference. Any other suggestions? I havent messed with anything but the trans related stuff. Ive gone insane trying to figure this out...
Originally Posted by GOaT Cheese
If the PCM sees any vehicle speed it will back out the IAC. If the 'puter thinks you are moving, it is going to try and behave like it.
Thanks!
