1.2 petrol 9n3 engine runs badly

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Joined: Thu Jul 12, 2018 4:46 pm
Drives: 9n3
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1.2 petrol 9n3 engine runs badly

Post by Astro_mike » Thu Jul 12, 2018 4:59 pm

I've a polo 3 door 9n3, 3 cylinder petrol, 2005 facelift. Bmd. I think that covers it.
It happened when it was very low on fuel, It was driving and started missing a bit at a roundabout then was ok for 1/4 mile. Turned off and collected friend. Restarted ok and drove for 50meters before it made a strange lump of a noise and stalled so I rolled off road and went a purchased some petrol.
Ever since then it will run fine for a few mins then starts to only run on 2 cylinders. If a turn engine off and restart it is ok again for another few minutes, repeat.
What we've tried....
We hung a small computer on it and it says fault with no1 cylinder misfiring.
Checked compression, it's ok
Swapped plugs around fault always remains with no1 Cyl.
Swapped coil packs around, fault always with no1 cyl.
Swapped plugs, still no1
Swapped injectors, still no1
Replaced filter,
Checked fuel pump, looks ok, gauze filter clean, what I can see in tank looks clean.
Wiggled wiring and cursed.
Any thoughts...

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Re: 1.2 petrol 9n3 engine runs badly

Post by alexperkins » Sat Jul 14, 2018 4:39 pm

Have you checked the timing? These are renowned for the timing chain jumping due to stretching

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