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Hi all,

My car has been rather idle lately as I've been overseas on a few extended work trips. I started my car last in May, and while it seemed to be running a bit rich, things seemed fine for a casual drive (except the battery was low on charge) and I did ~20 min run to the shops after checking all fluids etc.

I have it booked in for a general service and tune (car has ~115K on the clock, 5k but 1 year since last service, 10k since new plugs) so I decided to start it up tonight - surprise surprise, it needed a jump (battery still under warranty so no major drama there if it's toast). However, after idling for ~5 minutes, I decided to back it out - as soon as I went over 2000rpm in reverse, it started to surge/stall at a frequency of around one surge per second. The revs were bouncing between 800 and 2400rpm and the car generally sounded awful - even when putting back in neutral the idle was rubbish. So I turned it off and rolled it back in the shed.

I have a PowerFC, and when I had a quick look the Injector duty seemed too be bouncing from 0->10% and the timing (which had been sitting on 24deg at idle when cold) was seemingly between 10->35deg.

Can anyone please offer advice on where to start diagnosing this? I am hesitant to drive it to the workshop in this condition as it's a good 30 minute drive to get there...

Any and all help appreciated!

Thanks and cheers

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https://www.sau.com.au/forums/topic/370737-r34-rb25-neo-running-terribly/
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This is just a guess, but AFM?

I guess that could be reasonable, seeing as the one I have is from a Z32 and may be older than the car... is this likely to be dangerous to the car for a short drive? Temps will probably be around zero when I'm driving so I guess I shouldn't be at too much risk of overheating :blink:

Take it 100M down the road and back to see what it's like. If it is the AFM i think it will have trouble reving past 2000-3000rpm?

Don't blame me if you have to push it back home.

Have a look at this aswell.

http://www.skylinesa...your-rb26-afms/

Also remember it could be something else.

Edited by H4x

Thanks to all the suggestions - I was confident it wasn't bad fuel as I've not seen that allow the car to run OK at higher revs when running like crap at idle.

Got it into the shop today, looks like the issue was mainly a damaged O2 sensor plug + wire. Running much better now, just a few other minor things to address before I can bring her home!

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