Hi,
Thanks for the suggestions. Although I wish it were as simple as that, I don't think it's a diagnostic mode. It happens whenever I turn the key to position 2, without doing anything else at all.
I had a chance to look more closely under the hood yesterday. As soon as I turn the key to position 2 and the rev counter starts to spike, one or more relays in the fuse box start to turn on and off. I can also hear a high-pitched noise from the fuel rail, I think the injectors are being activated. To recap, this all happens without the engine being started!
I think the pump noise I mentioned is fuel being pumped through the rail. I'm pretty sure fuel is being sprayed into the cylinders during this process, and that the engine is getting flooded.
It sounds to me like the ECU thinks the engine is running and is triggering the injectors and spark plugs, does this make sense? As far as I know, the rev counter is triggered by ignition. Could this be caused by a bad camshaft or crankshaft position sensor making the ECU think the engine is being turned over when it's not?
Current list of suspects (in order of difficulty...)
- Bad ground (battery terminals, engine ground strap)
- Bad relay (can a relay fail closed?)
- Camshaft / crankshaft sensor
- ECU problem... I would have to admit defeat at this point
Can anyone recommend fuses/relays I could pull to narrow down the problem?
Thanks,
Ben |