Compression
- Thread starter cschell
- Start date
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If two adjacent cylinders are significantly low, then it might be the beginning of a head gasket problem. But like puppies said, withing 10% of each other and you're ok. Does the truck run ok?
- Thread starter
- #5
It runs fine. I was just concerned because the lowest is 20 psi lower than the highest which is more than 10%. However, it seems like decent compression for an original engine with 199K miles.
Just a thought for you - redo the compressions test but in reverse order. You may have had some cooling going on between when you did the first and the last cylinder. Funny enough, I have seen similar on mine, but when I warm it up again and redo the compression check (in reverse order) all of the cylinders are pretty much spot on at 140 or so (189k on motor). From the sounds of it - your motors tight, breath easy!