Misfires dont know where to look next
06-18-2011, 09:36 AM
#26
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Your lack of oil use & only slight difference between wet & dry compession would suggest that the rings are fine. You are probably heading for a valve clean & reseat/grind.
06-18-2011, 01:12 PM
#27
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2003 c230 kompressor, 1997 jaguar xk8
I did some checking and apparently my book is wrong, 150 psi is normal for this car. so could it be the plugged cat causing the hesitating? or something wrong with the supercharger?
Last edited by Smokphattys; 06-18-2011 at 06:47 PM.
06-18-2011, 07:04 PM
#28
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Sorry - I did not look up the compression specs for your engine & took your word for it. If there is a problem with the SC you should get all sorts of codes. I doubt that is the problem but we probably need to concentrate on that Cat. It seems we have proven that the engine is mechanically OK.
The Cat can only cause trouble if it is severely restricting the exhaust as I said earlier. Severe back pressure causes the O2 sensors to read all sorts of crap & will generally try to lean the system out which can cause engine stumble. It also prevents the engine from breathing properly.
If the Cat is creating backpressure I would expect the car to misbehave more and more as revs rise and the engine battles to pump & evacuate air. An engine is an air pump at the end of the day.
The Cat can only cause trouble if it is severely restricting the exhaust as I said earlier. Severe back pressure causes the O2 sensors to read all sorts of crap & will generally try to lean the system out which can cause engine stumble. It also prevents the engine from breathing properly.
If the Cat is creating backpressure I would expect the car to misbehave more and more as revs rise and the engine battles to pump & evacuate air. An engine is an air pump at the end of the day.
06-22-2011, 01:01 PM
#29
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2003 c230 kompressor, 1997 jaguar xk8
Ya thats what i was thinkin, unfortunately dont know anyone with a welder so I cant cut it off to be sure thats the problem before I pay thru the azz for a new one..
