Got a V8 1993 Ram showing low compression, doesn't seem to burn oil. Compression readings are around 60-80psi cold. Engine will not start, has fuel and has spark.

5/19/2010 7:13:39 PM

zxappeal has already looked at it a little

5/19/2010 7:14:22 PM

[no]

5/19/2010 7:27:00 PM

Catalytic Converter? I can't see how that would possibly affect compression.

60-80 psi on all cylinders or just one? Are you sure your compression gauge is good and you're threading it in far enough?

5/19/2010 7:27:30 PM

You want the intake to be unrestricted during a compression test(open the throttle body). I can't see how and exhaust restriction would have any effect on a closed cylinder though.

Pouring a tablespoon of oil down the spark plug hole didn't help?

[Edited on May 19, 2010 at 7:30 PM. Reason : Also make sure you pull the fuel pump fuse to avoid cylinder wash.]

5/19/2010 7:30:20 PM

Try a different tester and repeat the test a lot. It's really hard to get consistent readings. How many revolutions do you do? Are all the spark plug holes open?

5/19/2010 7:45:26 PM

dumb question itt

5/19/2010 8:14:25 PM

When my cat got clogged, her compression seemed to increase dramatically.

5/19/2010 11:25:13 PM