Had a new fuel pump fitted onto my 2004 330ci yesterday by a mobile mechanic. While working on the pump and the handbrake he had the driver's door open with the interior light on the whole time - hadn't disconnected the battery, even when doing the pump. Anyway, after having fitted the pump the car now won't start. It cranks over but won't fire up. I wondered if he'd flooded it as he had tried so many times to get it running. He put the old pump back in (which was still working, but at that stage when it was just about to give up - cuts out engine with around 1/4 of a tank of fuel; apparently very common in cars with around the 70k on the clock) and still wouldn't start. He then put the new pump back again and had another go at getting it running. Still no joy. Agreed to leave it overnight and try agin this morning.
Tried again this morning and still not working. Got Green Flag out and they've confirmed that there's the correct voltage to the pump, there's a spark at the plugs and fuel is reaching the engine at the correct pressure etc. They think that because the door was open for so long with the battery connected that the mechanic has done something to the immobiliser. Has anyone else come across this? I've done a search online and looks like this could possibly be the problem; I don't think it's the camshaft sensor or the starter, as the car was driving perfectly well other than the minor problem with the old pump. Any advice would be greatly appreciated - rang the mechanic but only getting his voicemail, and so far no returned call...
Also, if it is an immobiliser problem, is there an easy way to re-set? Or will I have to get the car to a garage for a full code diagnostic?