Strange fuel/electrical problem

2005-08-03 00:00:00

I've just come back from holiday and missed my car loads having not driven it for about 10 days. I went out for a quick drive this afternoon. Not much petrol, so stopped to get BP Ultimate first. With full tank, everything was fine. The car has been running very rich recently causing it to be a little lumpy at idle when cold and drop revs to about 500rpm at some junctions/roundabouts when slowing down.

Anyway, about 15 miles later, when pulling away in first at a mini roundabout the car 'kangarood' a couple of times - momentarily (maybe half a second at most) the revs completely dropped away and acceleration stopped before forward progress continued. No wanring lights came on, no strange noises, and water temperature fine.

About 1 mile down the road, it happened again, and then the engine died completely. After coasting to a stop, i tried restarting - it wouldn't though. I disconnected the battery using the battery cut off switch in the passenger footwell to reset the ECU. Once connected again, i tried restarting - the engine turned over, fired for about half a second then died.

It did this a few more times, then after about 5 minutes of trying fired up and settled into an idle. I cautiously headed for home. Though only managed to travel a further 3 miles before the engine cut out again - the revs just dropped away to zero from doing 30mph in 2nd and coasted to a rest again.

This time, i tried to restart, the fuel pump whirred and engine turned over, but it would not fire up. Tried using throttle also, but nothing. Called RAC.

Just moments before they arrived (they were only about 10 minutes - great service) i tried to start and it fired up. RAC man inspected the engine, base idle screw, distributor, etc, but couldn't diagnose the problem. We even made sure the petrol i had put in was infact petrol - it was. The RAC man followed me home - only 2 miles - just in case it cut out again. But it didn't, it behaved fine.

Question is, what could cause this?

One of my theories is that i had left the car with maybe 1/8th of a tank of petrol in it when i went on holiday and the gases had caused an air lock?

The stepper motor will also be inspected very shortly. but i would be suprised if this alone would cause the (intermitant) problem - i do clean it fairly regularly.

Perhaps it is linked with the rich running and the dropping of revs occasionally when slowly down for junctions etc.

The car is working again, so i guess i'll have to use it a few more times and see if the problem persists