Ignition Fault....Perhaps

[tauntonvilla]

Afternoon All. Hope you don't mind me asking for your help.

I'm hoping you may be able to offer me some advise on an intermittant fault i have with my 2000 (W) MGF.

Coming home from Coventry the other day, lane 3 of the M5, at approx 80mph,all ignition lights went out, and engine cut out. Just as if the ignition had been switched off and key removed. 1st time it happend i managed to make the hard shoulder. 2 time i simply turned the key, off then on again, and bump started. At motorway speeds, this was an experiance i tell you !!

I'm convinced it's an ignition fault. I've checked battery leads, any obvious earth leads. I've had the ignition cowling off, nothing visibly wrong.

Any ideas

Many thanks
Don

[colintf]

No idea Don, but hope its sorted soon!

[Charless]

I have heard of a similar problem some time back when a person who liked to sit too close to the wheel, or simply a very long person was so cramped up in their seat that their right thigh/knee inadvertently turned the key off! This was also on a motorway run - quite amusing once they realised the cause! Do you perhaps sit close to the wheel or have other heavy items dangling off your keyring? Just a thought.

[Rob Bell]

Let's hope something really simple! I wonder about potential electrical shorts (main loom chaffing against dashboard centre support) or a fault with the fusebox...?

[tauntonvilla]

I'll pay special attention to the key suggestion. I'm rather tall, however assume that i would have encountered this problem long before, as i've been driving this MG for over 9 years.

Ref the loom problem. Would it be possible that the bonnet light could be a possible cause. I removed it before having the bonnet painted around Christmas. The lamp is still to be refitted into it's slot, because i cant get it to illuminate when the bonnet is open. The wires are secure and isolated with tape, so i think it's unlikely.

[Rob Bell]

If all is taped up, then I'd suspect not.

Is all the electrical equipment working as it should?

[tauntonvilla]

If all is taped up, then I'd suspect not.

Is all the electrical equipment working as it should?

Everything else is working as normal.

[Charless]

9 years without previous key issue is pretty conclusive re driving position!
If you lost all of the 12v by shorting to the chassis anywhere, there would have to be a fuse blown through the path to ground because of the enormous current needed to short all the electrics, hence my suggestion of a key issue.
There are faint possibilities from loss of continuity in either the -ve or +ve feed of the alternator or the battery - hugely unlikely to be both at the same time - which would be the only non ignition way to cause the symptoms you report.
As Rob says, if the bonnet light did it, there would be a fuse gone very swiftly before normal ignition resumed. Stumped, sorry.

[adrianclifford]

Possibly a fault within the ignition barrel as symptoms seem to be centered around there. As the car immediately re-starts I cannot really see anything else that springs to mind.

I know of a friend who's car cut out at speed (non MG but the fact is the same) he switched off the ignition to re-start but needed to steer the car to safety before he chanced it. He ended up hitting another car because he lost his power steering without realising it would happen.

[Helsbyman]

Sorry to hear about your fault BUT after 9+ years it could still be you are touching it and NOW the barrel IS worn