Jimny losing power and cutting out with warning lights

Well lads, new member here... I recently bought a 2002 Jimny and am having a small issue.A few times now when driving, it starts to lose power, and the engine warning light and the immobiliser light starts flashing. The rev counter seems to be going wild too. When I turn it off, leave it for a min or two and turn it back on it's a little bit slow to start but then gets going again.It happened twice on the motorway and once going up a hill. I think it happens mostly around the 3000rpm mark too.Has anyone seen this before or know what it might be? Any info would be greatly appreciated.Cheers.

The usual cause is the crankshaft position sensor hidden between the alternator and the block.

The lights flash and the rev counter drops because it thinks the engine is stopped when the signal disappears. There won't be an error code though as it thinks the engine just stalled.

Thanks for your reply.

Would this also explain the immobiliser light flashing on do you think?? I have a sensor on order so will replace it early in the week.

Some people on a Facebook page mentioned about an earth strap, an ecu being damaged or a blocked cat!

Lack of power is often a blocked catalyst, but the rev counter dropping means the engine is stopping.

May actually be a bad earth, fractured cable or another fault like a coilpack breaking down (a missfire would set a fault code though), but the M series go through crank sensors like an elephant goes though sticky buns, they are cheaper than a diagnostic, and easy to change so worth a punt ( as the first shot of the parts cannon )

I had a similar experience with a Vectra 25 years ago,, sudden loss of power most dashboards lights flashed, speedo and rev counter went erratic, full scale, down to zero, repeat, then the engine died.

I coasted to a lay-by on a busy road and lifted the bonnet, the unmistakable smell of burnt wiring. It was a lease car so I was just getting ready to call the break down when this bloke stopped, said ‘they all do this’ and before I could stop him, he reached in and pulled a wire out of the harness, then said it would be fine and left.

The car did start and run ok, so took to the garage. I never saw the bill, but think they replaced some of the wiring harness in the engine bay.

Hopefully it will be your sensor, but when I read your post I thought if it isn’t the sensor, it might well be an earth or wiring. Mice are known to chew through the insulation and you get a variety of weird electrical problems.

Robin

Thanks again for your reply and info.

I put in two new ignition coils the other day. I will get the new sensor in this week and hopefully that solves the problem! Will keep you updated absolutely worth the punt.

Cheers