Rossy43

My cosworth has started to idle funny after a long trip out this weekend.

On cold the car will idle around 1500rpm. It used to idle perfect at around 1000rpm. Once the car is up to temperature the idle will hunt between 1000 and 2000rpm with a very distinct pattern. Ive doneno work on the car to potentially cause this problem recently. Any ideas?

Note...I tried unplugging iscv when hot and it made no difference.

Search didnt really give me any definitive pointers.

Thanks guys.

mark r

try un pluging the idle valve,if the problem cures then id say idle valve knackered.

mark

Rossy43

Cheers mate. I tried that and nothing changed. Forgot to put that in post.

martysmartie

iTrader: (1)

You have an air leak, possibly around the plenum area...

Martin

Rossy43

So im looking from the tb inwards or can it be anywhere?

martysmartie

iTrader: (1)

Correct, it's most likely a plenum gasket etc, you can use WD40 sparingly as a tracking aid.

Martin