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Q: No compression on two cylinder

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Vehicle overheated... Rebuild the heads and all the gaskets but now I have two dead cylinders cannot figure out if I am maybe you one tooth out of time or not I'm not sure but have absolutely no compression on cylinder number 2 and number 5....vehicle does run just with 4 cylinders
My car has a manual transmission.

A: Hi there: Although it’s impossible for me ...

Hi there:

Although it’s impossible for me to know without inspecting the vehicle onsite, I’m not quite certain the compression issue is mechanical here. It’s quite common after a head gasket change due to an overheating issue for the crankshaft position sensor to be faulty; which could cause ignition timing problems or faulty readings on compression sent to the ECU. There are multiple engine monitoring sensors that should all be changed anytime you remove the cylinder heads and complete major repairs. However, it’s also possible that a bent intake or exhaust valve, a leaking head gasket is causing the compression issues.

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