Eggplant Jeff

I've been having a long-running idle problem, described in my "completely out of ideas" thread (probably on the second page now). Anyway I had the car at my mechanic's for an alignment and I was talking with him about this problem. He suggested that if it isn't a vacuum leak, and it isn't a fuel problem, that maybe it's a problem with a valve, lifter, or the cam. Like, a worn camshaft node or lifter that's not lifting enough or something.

What other symptoms would I look for? What tests can I do to check for this sort of stuff? I've got some pinging too, I think the computer may be yanking timing because it feels sluggish sometimes when it pings, but if so it isn't helping.

My mechanic suggested a compression test, I guess it couldn't hurt but I need to get a compression tester :-(. No parts store here has one that works.

Damon

Your mechanic is right- compression test is what you need to do. Beg borrow or steal a compression guage, yank all the plugs, disconnect the ignition, block the throttle wide open, and do a test on all 8. Make sure you get at least 4 compression strokes for each cylinder you test. The raw number doesn't matter so much, just whether the numbers are close to EACHOTHER. If you have 7 between 160-175 and then one at 120 you've found your bad cylinder.


------------------
94 Firebird Formula M6- No options but Z rated tires. No mods over $10. 13.5@105.
79 Malibu "beater" w/junkyard 400 SBC, tweaked QJet 4bbl, finally a decent set of heads, a few other tricks. A maddening 13.000001 @ 108 on the motor with little traction. No nitrous runs with the new heads yet.
Grandma's old 78 Malibu (33K miles!) soon to have the powertrain from the 79 put in it.

"One of the last remaining QJet tuners on Planet Earth!"

[This message has been edited by Damon (edited September 28, 2000).]