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Q: low compression on number 5 cylinder

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Compression is 75 and I'm pretty sure it's a blown head gasket but the car misses all the time and the plug was wet but it only smell like fuel but couldn't really tell my coolent is a little dark but not bad.

My car has 75000 miles.
My car has a manual transmission.

A: Low compression in a cylinder can be from d...

Low compression in a cylinder can be from different things. The piston and its rings, the valves leaking, a head gasket leaking, or a cam lobe worn. A broken spring for a valve may also be the problem. If you have a cylinder pressure leak down test to see where the pressure is leaking, this will tell you what is the cause of the low compression. If you want a technician to check this for you, they can look for any leaks and inspect the misfire to determine what is going on.

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