Engine Performance problem
2007 Ford Mustang V8 Two Wheel Drive Manual
Can a clutch/transmission problem cause the wrench light to illuminate without throwing any codes? Or is a faulty PCM the cause?
No problem starting car or problems with idle immediately upon starting. However, intermittently upon driving 2-4 miles, at idle with clutch depressed/neutral at stoplight, tach will fluctuate between 500 & 750 rpm as if it will stall. Once when stopped, the car engine just quietly shut off (didn't shudder or buck).
At other times while driving normally, the ETC lamp (wrench light) will illuminate and engine goes " limp-mode". When pull over, turn off ignition and then restart, seems to run okay. No check engine light. Although otherwise runs good and accelerates quickly when depress gas pedal aggressively, there are times when some sensation of a momentary vehicle slowdown is noted while driving normally--like it's lugging/not a full power and I have to downshift or give it more gas. The clutch doesn't seem to slip so far as I can test, although I do sometimes detect a faint burnt smell with stop & go driving and when shifting a lot in traffic Engine stalls when slowly release clutch in 5th gear when at a stop so clutch isn't " toast" yet.
TPS replaced, MAF sensor cleaned and ultimately throttle body assembly replaced. Haven't stalled at a light lately, but idle rpms still do sometimes dip momentarily to 500 for no apparent reason. The car does not move forward with brake off and clutch pedal depressed while in 1st gear so presumably the clutch disengages adequately. Wrench light came on again. Two mechanics (one Ford, the other independent) looked at car. Found no codes or anything obviously wrong. I have had a Whipple supercharger and Steeda Adaptive Calibration tune for the last 2 years without a problem with parasitic drag. What should I do next?