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Old 04-23-2010, 08:06 PM
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cobalt327 cobalt327 is offline
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Quote:
Originally Posted by kellynova
I have checked comp 135-150 hole, found bad plug wires, replaced cap rotor plugs wires. also checked timing??
Check to see that there are no vacuum leaks and that the vacuum advance works, and is connected to manifold vacuum.

If more initial timing and/or more accelerator pump shot doesn't cure it, there may be other problems. The compression should be higher than what it was, unless the cam is quite large, or the engine quite worn, like rings, valve seal and timing retarded due to a worn/stretched timing set.

The compression reading should be done w/a fully warmed up engine w/the throttle blades wide open and ignition disabled. If a squirt or two of oil in the plug hole doesn't improve the readings quite a bit, you could be looking at worn valves or badly retarded cam timing.
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