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Evening,

What is the most common cause of misfiring - vcds is showing miss fire on 3 cylinders. P0301,P0302 an P0303.

Its very intermittent and seemingly worsened with rain - I think it's therefore electrical, coil pack??

Any ideas?

These cars don't have a coil pack. They have a DIS module (distributor less ignition module)

It could be that causing the problems

i'm going to douse the engine bay in WD to mask the problem - im sure it's water causing the problem as when it's raining is when it occurs.

i had it today but with only moderate rain - occurs when pressing the accelerator with low revs.

What spark plugs are fitted

Have you checked your ht leads? A couple of mine were split and on a damp day it would missfire

Sent from my GT-I9300 using Tapatalk

- plugs are Bosch if I recall correctly (not had a prob with these in 5yrs)

- leads were changed 2 years ago and look fine.

Vcds - misfire on cylinders 1,2 and 3. Surely plugs wouldn't have failed on 3 separate cylinders would they?

It could be the plugs quite possibly... Plugs only last 2 years realistically.

Is it best to put ngk ones in?

Best to get genuine ones

Ngk triple electrode ones are the standard figment

I used to use Bosch super4s in mine, but went back to genuine ones as they started causing issues.

Right, replaced the leads and plugs today and noticed a fair bit of oil around the plugs. My first thought was my rocker cover gasket.

Is there a guide to doing the gasket on here or does anyone have one?

Assuming it is that of course

Rocker cover gasket is a major task. The cams have to be removed as they run through it!

It's likely the oil has been overfilled and run Into the spark holes

What's the best way to be sure the rocker gasket is ok/ how can I rule it out, Alex?