Hi guys, I had a misfire on cylinder no 5 for sometime due to a coil is not fixed properly until it was fixed after 3 weeks or so.
Now i was cleaning my valves and here are the pictures sent to me, am not sure if something is wrong with no 5 valves i have a feeling that its bent or not seating properly and there is a gap.
The dealer said compression is perfect, I was cleaning valves because of carbon deposit was excessive and I experienced lack of power and vibration during idle.
I just want to make sure everything is good once and for all as all these problems just started after the misfire i mentioned because of the coil.
could incomplete combustion cause intake valve to bend or slightly leak?
i did not try the car yet after cleaning as it still there but this cylinder makes me suspicious.
Done correctly, Ahmed, compression tests don't lie. If a valve was not seating - for any reason, compression in that cylinder would be noticeably lower than the others. The photo above, while it does not show the actual PSI of each cylinder, it does show that all 6 are very close to each other.
Incomplete combustion won't cause a valve to bend. The only thing that could cause the head of a valve to get bent is contact with the top of the piston. For that to happen the valve got stuck in the valve guide, likely to insufficient lubrication, or the valve spring is weak or broken.
I'm curious; just how are you "cleaning" those valves?
Done correctly, Ahmed, compression tests don't lie. If a valve was not seating - for any reason, compression in that cylinder would be noticeably lower than the others. The photo above, while it does not show the actual PSI of each cylinder, it does show that all 6 are very close to each other.
Incomplete combustion won't cause a valve to bend. The only thing that could cause the head of a valve to get bent is contact with the top of the piston. For that to happen the valve got stuck in the valve guide, likely to insufficient lubrication, or the valve spring is weak or broken.
I'm curious; just how are you "cleaning" those valves?
Thank you for clarifying this, really appreciated.
They removed only the intake manifold since the valves are accessible and then used some solvents and blast the carbon out of it , not sure about the exact details and machines used.
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