Hi Guys

im new to the forums (still yet to introduce myself)

I bought a GC8 4 weeks ago, had high km, body was in good condition, 3" dump and exhaust, front and rear whiteline sway bars and a unichip

2 weeks ago it was hot in adelaide, and we washed the car while it was running, totally forgetting the previous owner put a pod filter on it, right below the drivers side bonnet vent.

Subsequently it sucked in a heap of water, however the water didnt stay long in the engine and it soon cleared out.

Since then, the car has had a rough idle and is down on power, im guessing a good 25-30% in power, but its still very driveable and still damn quick.

It has a misfire around the 4500rpm which we cant seem to get rid of, aswell as cant seem to find the missing power.

a week ago i washed the car again, put a plastic bag over the pod, removed the bag and started it up, and it was idling fine, and had all the power back right up untill i switched it off again.

So far i've replaced

Fuel pump
Fuel filter
plugs
leads
air flow meter
air filter (pod filter)

This morning i plugged the black and green connectors in under the dash and from what i could see it pulled up error codes 22, 23 and 53

Im yet to fix these codes but im looking at doing a compression test in the next few days as i believe it may well be a more serious problem then just a sensor.

I've done some reading and everything i've looked at seems to refer back to cyl #4 and burnt valves.

Has anybody encountered a similar problem in terms of roughness, misfire and lacking some power? it almost sounds as if its running on 3cyls but its definately not.

If it is a burnt valve, how much is it going to cost to get the heads rebuilt?

Its my first subi, i dont know much about them :|

any help would be appreciated


adz