Well she died on me
I was driving home, got on the interstate and the CEL came on, the RPM dropped to zero and I coasted to a halt.
When I tried to start her, I could hear what sounded like a short-cycling relay under the dash when the key was turned. The starter would turn, but the engine wouldn't catch. I waited a while, then tried again and she started up (CEL stayed on) and I was able to drive it for maybe 400 yards. I did this repeatedly trying to get to an 'Auto Zone Near Me' but eventually she died and wouldn't restart. I got a tow to the AZ (stupid really as I should have gone directly home) got the codes read and had two:
P2610 - PCM Ignition Off Internal Timer performance problem
P0685 - ECM/PCM internal circuit malfunction (Power Control Circuit)
and the recommendation is: Repair Engine Control Module
I eventually did get towed home, parked the car on the front and was able to drive it round the back this morning. I called JDM and they said it was my old ECU on the vehicle, that they hadn't replaced that, which is true or they'd have had to reprogram the keys and they said they hadn't changed the wiring harness for the ECU
Because the car will drive from time to time, I have the feeling that it's merely a bad ground or a bad connection somewhere - though where, and whether I'll ever find it is a different matter. I'm not about to go throwing money at the vehicle
I did look up used ECUs on ebay, but also read about the VIN and immobilizer programming involved. One YouTube even suggested desoldering the chips from the old ECU and soldering them into the new ECU as a way to avoid the reprogramming - lol
Anyway, that's where it stands right now. Anyone have any ideas where the ground/connection fault may be?
As for JDM, I have to agree with them that it's not a warranty issue if they didn't change the ECU, though I did read two posts above "a JDM motor, you have to switch over the wiring harness" so I'm not sure about that part yet. If someone could explain what that phrase means.
I'll keep you all posted