Hi there,

After a bit of advice, my 03 cooper s has developed a loud ticking from the drivers side of the engine bay. Have seen issues like this on tickover and under acceleration, but mine is only ever under load when in high gear at slow speed, with foot down. Seems to run in tandem with the supercharger.

Have stripped the engine to look at the sc and seems to be in very good condition, also did a compression test before striping and 1 & 2 are running at 90 psi each, where as 3 & 4 are running at 150 psi each! Valves all look fine, no oil in coolant and no coolant in oil, so not sure what's causing the low compression?

The ticking noise started after changing the coolant, don't know if that's a coincidence!

Anyone had similar issues with compression low or the ticking? Any help much appreciated

Cheers Rob

You need to carry out a leakdown text to see where the problem lies. You will get air out of the exhaust, dip stick, coolant bottle etc an that will tell you where you compression is having problems.