TL GTVi idling issue fixed.
I recently puchased a nice TL GTVi FWD with idling issues.
It run like a dog on the 100k drive home and was as thirsty as hell. The idle was rough and occasionally the car would miss. Also showed CEL and traction control wouldn't work.
On a whim I pulled the front plugs just to see what was in there and how they looked.Black and sooty....okay ,rich mixture. Checked codes and 12 came up,air flow sensor.
Cleaned the MAF sensor ( lets not go feral here, thats whats its generally known as by most mechanics).No real change.
Swapped for another MAF,now good idle but sitting on 1200rpm.CEL gone
Pulled IAC and cleaned,no change,still high idle.
As I'm looking in that area, I notice the throttle stop screw was wound in a fair bit compared to my other Magnas and the "seal " paint was broken.
Reset the stop screw per manual.
Now idles nice,no check lights, car is much better,idles around 800 rpm
I also checked the TPS and traction control TPS, both good. ( They are not interchangeable btw, one rotates clockwise the other anticlockwise) Makes sense when you look at throttle shaft rotation.
Hope this helps if your having idling issues.
I'm guessing at some point before I bought it, the throttle stop screw was played with with to address the rough idle problem.Doing this wont fix the underlying problem, which was the faulty MAF sensor,which is easily checked using the CEL code.
Now, which car to keep? The GTVi or the TJ VRX limited edition with full leather,sunroof, lowered,chipped, extractors,5 speed manual, ratty peeling clear coat. The TJ might be a winner....the GTVi is nice, but the VRX is animal....