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· Registered
1 Posts
Discussion Starter · #1 ·

I have looked back at previous posts and although similar I've tried to go in more detail to pinpoint the problem and hopefully this will act as a reference point for others who may have a similar problem in the future.

The symptoms appear to be lack of power (acceleration) and spluttering driving. After a few days of this the engine warning light lit up. Having read it with a reader it's reporting a P0304 code (Cylinder #4 Misfire).

When this came on I messed about with the plug leads thinking one could be loose. As I did this, cylinder #2 code (P0302) came on as well. The car is totally undrivable when two cylinders are knackered! I therefore replaced the leads, this fixed cylinder 2 (guess I damaged the lead?) but cylinder 4 was still misfiring.

Anyway after getting a wrench to get the plug out, plug 4 appeared very 'sutty', it looks like a bit of oil fouling on the tip (electrode?) of the plug. I got the other plugs out and they appeared clean and in good order. To try and isolate if it was just a dodgy plug, I swapped 1 and 4 around. The code remained and the car remained sluggish. After getting the formely plug 1 out of number 4 it went sutty despite being clean when it was put in.

I have now just replaced all the plugs but I doubt this will sort the problem, the light I am sure will reappear at some point although current performance is fine (I imagine it'll go back to sluggish performance once the plug has clogged up again!).

Any ideas what this could be? I guess the next stage is the coil but does this sound like a coil problem?

· Premium Member
22,770 Posts
Intake valve seal leak- that's my guess. Are you seeing any gray smoke from the exhaust?

Also, I'd do a compression test on #4 to be sure it has correct compression.
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