I recently picked up an 03 Z06 with 165k on it. The car ran great until very recently, when it began giving me a random "Reduced Engine Power" with the corresponding lack of fuel level, oil pressure, and max'd coolant temp. Nothing has really changed and I have driven the car for around 500 miles prior to the issue with no problems.

The most recent mods I have done were to add switchbacks in the front and the CF13 resistor to the flasher wiring. The issue began prior to the install of the CF13 resistor, but I don't believe any of the mods are related. I had also recently cleaned the air filter (conical filter on a breathless vortex intake) and oiled it with WD-40. I was thinking perhaps some residual oil got on the MAF, but the "Reduced Engine Power" seems to pop up at random. On some starts, there are no issues and the car drives totally fine for 15 or 20 minutes; other times it happens immediately.

I have looked under the battery and tray and all the wiring looks completely fine. I have also read to check the door connections, but haven't gotten that far yet. I know the DS power seat connection appears to be fine, with no pins bent. Anyone have any inputs?

Also, as far as codes on the DIC, the maine one I have is knock sensor 2 being bad, but nothing else that really relates.

 

I believe I fixed it: I also recently installed a Vette Nuts insulation kit for the car and upon reinstalling the carpet and seats I did not allow the DS seat harness to clear the seat attachment point. I believe the wiring to the seat was being pinched and shorted. After routing the wiring free of the seat attachment point, the car drove completely fine for the past hour with a couple shutdowns and restarts (I went into a few stores; everything operated as expected and normally).

I’ll update this thread if the problem returns, but something to be aware of.