Engine suddenly cuts out!

[kush7]

Hi all,
I have a Sierra XR4x4i, the trouble is that all of a sudden (without warning) the engine & electrics just cut out, it's happened about 4 times in the last month but it 'always' restarts again. Ive checked battery connection, fuses etc are all are ok. Someone mentioned that it could be the engine management chip on its way out, however, I think it might have something to do with the electrics of the fuel injection system.

I also have a alarm system that is connected to fuel pump & electrics & that could be playing up. Any ideas/suggestions would be greatly accepted.
Dave

[Fergerino]

Howdy kush7, and welcome to the forum!

If your problem is related to the engine management unit, it wouldn't necessarily have to be the unit itself; it could be one of the peripherals connected to it.

I had a similar problem a few years back on a Renault 19 - it would cut out without warning. In my case, it turned out to be a faulty water pressure sensor that connected to the engine management unit. The unit received info saying that all was not well, so it decided to stop running the engine!!

I'm not so sure that your problem is related to this though, coz you that the electrics cut out. If you mean that even things as basic as the lights cut out, then it's unlikely to be the engine management unit. These two circuits are unrelated and won't affect each other.

Hope that's some help.....

Cheers
Fergerino

[Dom]

Some ideas for you.....
on some injected Sierra's there's a fuel cut out switch under your spare wheel, check and make sure the switch isn't failling or gettin knocked by a loose spare wheel, also check coil hasn't got an intermittent fault, doesn't sound likely, I know, but I had one where that was the cause (with the same symptons) other problems I've had that gave these symptoms were wire's rubbed through by the alternator - touching occasionally - car would stop but then start again after. Also ignition switch breaking down might be worth a look at , had one before, everything worked but it turned out to be that.
Hope this gives you some other things to try before you go for the alarm.
Good Luck!!!!!!!