The car is having a super hard time starting, but ONLY when the engine is stone cold. Either my fuel pressure is bleeding down over time (possible leaking-down injector?), or it is related to the temp sensor, with the ECU not knowing what to use as a base temp for scheduling fuel during cold start. There a couple of other issues that may or may not be related: there is a #1 cylinder missfire at high engine loads. This might support the leaky injector hypothesis, of more likely be a bad coil pack or ICM. The other possibly related issue is that the aux cooling fan constantly cycles. Without access to Bentley, I'm not absolutely sure if the thermal switch located in the lower radiator hose has any input to the ECU for fuel management, or if it only sends a signal to the fan control unit. My understanding is that the temp sensor behind the RH cylinder head drives the gauge reading on the dash, as well as letting the ECU know the coolant temp. Do I have this right, or could the fan thing and the hard starting be traced back to a single sensor?
I have ordered a coolant temp sensor as well as an in-line fuel pressure gauge from ECS for troubleshooting. Any other thoughts from anyone?