My 99 has started pulling timing as it reaches the low end of operating temp, and I'm running out of possible sources other than changing the wiring harness.
It didn't do this last year. I've installed a practically new motor with mostly new sensors that dyno'd well before installing. I pulled the dash over the winter since this began as well. I know it's supposed to pull timing at 204F. I'm watching it happen between about 150 to 160F using an IR pyrometer on the heater hose coming off the back of the engine. It pulls timing as much as 10* and is noticeably slow, not even being able to hold a draft from a good but not great car.
I changed the ECU with no effect (other than my fuel pump turns on normally now). I changed the temp sensor on the back of the engine. I've swapped out the throttle body and I've changed the top of the air box with the sensors there as well.
I can see that the O2 sensors have been spliced together, and the one from aft of the catalytic converter is plugged in, but someone stuck some resistors in the wiring for some reason Can O2 sensor faults cause the engine to pull timing? Any other ideas here are appreciated. I'm starting to run out of stuff to swap.