knocking/stalling at motorway speed

Hello,My girlfriend has recently brought a Jimny and it has an intermittent problem when driving on the
motorway.
I have not experienced it but it appears to stall and cut out only when at motorway speed.
She has been recovered from the M25 and garage diagnostics could not find the problem ?
It sounds to me like she has dirt in the carburettor but i dont know much about the Jimny and joined the site on her behalf !
Has anyone any ideas or have had a similar fault ?
Thanks
Dean (ejimny)

Welcome Dean

Could be fuel starvation but would normally restart dont think any Jimnys were fitted with carbs so doubt it will be that as far as i know they were all EFI.
Could do with a bit more info if you can does it restart after a while or is it now a non runner ?
Does it give any warning its about to cut out like the engine is holding back or does it just cut dead

Dave

Hello Dave,Thanks for the quick reply and for your info.
I wasn't sure about the carb thanks for pointing that out !
The problem only happens in top gear (2 wheel drive) on motorways and she said it appears to stall
as if theres no power and seems very lumpy.
It happened a few times until she pulled over and called the AA who didn't check anyting and just sent out a third party pick up truck to get it to a local trusted garage near me.
They took it out on the motorway to check it and found no problem.
I then followed her up the motorway and she had the same problem again and pulled over.
It starts again fine and was ok for the rest of the journey.
She took the Jimny to her local garage who ran a diagnostic and didn't find any fault other than saying it needed a new clutch £700 :huh: + full service
My local trusted garage will be doing the work for much less !
It still dosn't explain the problem she is getting and is a bit worried every time she uses it now.
As far as i know it dosn't actually cut out but she said it feels like the power drops off and judders
as if it will stall.
Thanks again
Dean

ignition leads , coil ?

have a search of "rev needles jumping" on here, see if that fits the bill

as it could be the cam / crank sensor faulty, this is a common fault

Thanks for the info that is very helpfull
cheers
Dean