My 1988 Chevy G 20 van with a 350 small block overheated the other day I was able to start and drive a vehicle a few miles that I parked it for work when I left work hours later it wouldn't stay running had a really rough idle high and low I was able to limp it home with very minimal RPMs would never get over 35 miles an hour I've done pressure on my cooling systemthe no leaks I replaced the rotor and distributor cap along with that PCV valve and a throttle position The rough idle has Subsided unlit I put it in gear now I don't know what to do next
My car has 20000 miles.
It sounds like you may have a the beginning of a blown cylinder head gasket. A blown head gasket may cause a number of different symptoms. A head gasket that fails between cylinders will generally cause a misfire and potentially compression leaks from one cylinder into another. Low compression will eventually result in a rough idling engine. When the head gasket fails between a cylinder and the coolant port, coolant may leak into the cylinder causing it to be burnt with the fuel charge in the combustion chamber. This often results in misfires on startup, especially after the engine is run, turned off and restarted and in some cases may result in the engine not maintaining enough cylinder compression to even run or start. This type of failure may not always show with a compression test. I would recommend having an expert from YourMechanic come to your location to properly diagnose the symptoms you describe.
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