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s code low compression

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MarkC:
s code 390 150 lbs compression except cyl 2 is at 60 lbs,but passes leak down test,any ideas

RoyceP:
Typically it means either a leaking valve or bad rings. You need to pull the heads and see which it is. Cold Cranking numbers like that on an FE are indications of trouble. It indicates low compression of course, but compression ratio is more likely calculated, not measured.

J_Speegle:
First welcome to the site.

Not really our focus here and you may be served better on a different site but lets get some of the basics out of the way.

Was the test done wet or dry?

Has this engine been sitting for a while?

If so have you thought about putting a scope down that hole through where the spark plug attaches?

lightwtjet:
As Jeff may have eluded, an engine sitting for years can develop stuck rings. Simply driving fixed mine.
Here is more of what can be learned from a leak down test.
https://www.mobil.com/en/lubricants/for-personal-vehicles/auto-care/vehicle-maintenance/h

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