[stphnsns]

Hi guys, I have an ongoing issue on my 2006 C4S coupe, that I've been chasing off and on for about a year. I revised an old Renntech thread, but didn't get any replies, so thought I'd try over here, and see if anyone has any insight!

Essentially: Higher than normal idle (1200-1500: goes up as car warms up), lack of power upon acceleration (probably 50-60%), and failure of sport mode to activate. Those are the primary symptoms. Now I just noticed that cruise control won't activate (light on dash works when you first turn the key, but no light or cruise when you try to activate while driving). We replaced the throttle body last year, and thought that did the trick (seemed to for a while). I just this week replaced the gas pedal assembly, as I've read - like the TB - the potentiometer in there can fail. Also in the last year, we've replaced the water pump, AOS, and drive belt. My lucky year! Anyway, after about 3,000 miles, the problem has returned. It did a couple months ago, but after disconnecting the battery, it self corrected - for a time. Now its back and nothing I do seems to help. I removed the MAF completely, and the idle drops down to normal-ish, but there is ZERO acceleration. I assume that tells me the MAF is good? My other hint is from Borrowed knockoff Durametric software, I got the following readings (there has been NO CE light through any of this, and yes, the CE light bulb works)

Codes:

P1514 - FACTORY FAULT CODE 540 - THROTTLE JACKING UNIT LOWER MECHANICAL STOP

P1511 - FACTORY FAULT CODE 543

P2126 - THROTTLE ADJUSTING UNIT - POTENTIOMETER 2

P2121 - THROTTLE ADJUSTING UNIT - POTENTIOMETER 1

P1517 - THROTTLE JACKING UNIT ABORTION OF TEST

I believe that test was while running. When tested not running, the only readout was P1514.

Those codes would indicate the TB or pedal, but to no avail. One other consideration is the clutch cruise control switch? Hate to keep throwing money at it. Unfortunately, no dealer - or really even a qualified indy with Durametric anyway, close by.

Would love to hear if anyone has any insight or related experiences. THANK YOU!