misfire !!!

[gogsy400]

yet another misfire,my chimaera has developed a slight misfire ,the usual between 1200 1800 rpm,have changed the plugs,leads,cap,rotor,and coil to no avail.have just had a diagnostic done on it and the number 2 cylinder has the issue,changed fuel injectors around to see if it was blocked but misfire stayed at number 2 cyl.the guy that did diag reckons a piston ring may have failed and is oiling up the chamber.is this possible? or is there something else i should be looking at!?
thanks
gordon

[swallet]

when you say "had diagnostics done". What exactly? Is cylinder 2 down on compression?

[swallet]

when you say "had diagnostics done". What exactly? Is cylinder 2 down on compression?

[PH430]

Did you do a compressiontest?

[gogsy400]

compression test was done,all cylinders have good compression cylinder 2 was slightly higher than rest,they used a temp laser on manifold,cylinder 2 was much cooler than rest,ht lead showed it had spark and pulse at injector.

[blitzracing]

Check the plug colour on 2- oil fouling will be pretty obvious compared to a good plug

[gogsy400]

had the plug out and it did look pretty oily,sounds like bad news .

[Steve_D]

Quite possibly the cam has gone.
Difficult to test as the hydraulic lifters can leak down as you are trying to measure the rocker travel.
You may have to remove the rockers before you take your measurements.
You don't need anything sophisticated to do the measurements as, in our experience, the worn cam lobe will likely have 4 or 5mm less lift than it should have so a simple steel rule will do.

Steve

[gogsy400]

Thanks steve will get it checked out,is there any other things i should be looking for ?
Gordon