juddering/rough idle

[woosey]

Hi guys,

Got a 57 plate 'justa' cooper with the n12.

It's got a rough idle (doesn't stall though) it hovers between 650 - 850 rpm and at around 1800 RPM in 4th when you accelerate the car judders, in other gears you don't seem to notice this, i assume it's because it's more strain on the engine.

Any ideas guys? Thinking of changing the spark plugs & HT leads, are the coil packs ok on these cars? Car only has 37k on it!

[ALD0]

It could be any that you mention.

Unfortunately these engines suffer with a build up of coking too. It may need a de coke.

Also try a high pressure fuel pump too.

Mine had both of the above to cure similar problems.

[woosey]

Quote: Originally Posted by ALD0 (original)

It could be any that you mention.

Unfortunately these engines suffer with a build up of coking too. It may need a de coke.

Also try a high pressure fuel pump too.

Mine had both of the above to cure similar problems.

being a 'justa' cooper i don't have the coking issue, or a high pressure fuel pump

Checking the part numbers of the ignition coils, they match that of my old E60, which had all 6 replaced under warranty due to issues with them failing early (via a campaign) so i'll throw that in on thursday (it's off to mini under warranty)

[woosey]

sure enough 4 new coil packs from mini under warranty and the problem has gone