Q: Whats the best way to fix a low compression valve?

asked by on March 23, 2017

My 3rd valve is giving 80 lbs of compression.

My car has 221000 miles.
My car has an automatic transmission.

Engine is misfiring Inspection $94.99 - $114.99 Get a Quote

Hi there. When it comes to having a loss of compression in an engine, there are 4 locations that can contribute to the leak.

Locations:

  • Bent or burnt intake valve
  • Bent or burnt exhaust valve
  • Hole in a piston or the rings are not sealing
  • Burned head gasket

If you have a loss of compression and it is 80 lbs, then hook up a leak down tester (requires compressed air) and determine where the leak is coming from. If the engine has a leak on the intake or exhaust ports, then the cylinder head will need to come off to replace a bent or burnt valve. If the leak is in the radiator, then the cylinder head will have to come off to replace the head gasket. If the leak is coming out of the dipstick tube or the oil fill opening, then the engine will have to be rebuilt to fix the loss of compression. If you need further assistance with your loss of compression on your 3rd valve, then seek out a professional, such as one from Your Mechanic, to help you.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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