bwright138

The car: 1992 SL2.
The Problem: I have replaced the spark plugs many times but within a few hours of replacing them (and only when the engine's hot) the engine is misfiring or something again. I know it sounds indicative of head gasket, but I don't think that's it. Before I had been fouling plugs, and every time I replaced them it ran fine... for awhile. Weird problem! Any suggestions would be great... Thanks!

sierrap615

what are the considitions of the plugs when you remove them? do you have a multimeter? what type/brand of plugs are you use? are you burning oil? mileage? idle RPMs? can you do a compression or leakdown test?

cousincletus

If you're burning a lot of oil they can start fouling in a couple hundred miles. I would remove the plugs and check the condition also.

bwright138

I'm not burning any oil. I fouled plugs until I did an oil change and ran some marvel mystery oil through it. The vehicle had been sitting for a few months due to lack of a transmission. I just put a new transaxle on it about a month ago. Mileage is 163k. Is a clogged fuel line/bad gas/fuel filter a possible culprit. I hav a compression tester and a spark tester (conventional) but I've never done a compression check before. Hence I'm pretty sure I have a good idea how to do it, but I am unsure. Should I remove a plug, find BDC with a screwdriver, screw in the comp. tester and turn the crank? Thanks for your help.

sierrap615

what plugs are you using?

for a compression test, remove the spark plugs, disable fuel injectiors(pull the fuse), screw in the tester. make sure the tester is reset to zero, crank the engine for ten compression strokes(with the tester in, the compression stroke will sound more noticeable then normal). record your reading, repeat for all cylinders, that is a dry test, after you do all cylinders, then do a wet test, pour a little oil in each cylinder before you test it.

heres a better how-to - http://www.dsmgrrrl.com/FAQs/compression.htm

they say four strokes, saturn says 10. spec is 180 after 10 strokes.

a leak down test is a little more involved - http://www.geocities.com/dsmgrrrl/FAQs/leakdown.htm

bwright138

I am now currently using bosch double platinum (pre gapped to .040 to make sure). Any suggestions as to what else may be the problem if it truly is not a head gasket issue?

sierrap615

trash the plugs. platiums look pretty, sound nice, but work like crap. oil destroys the tips. try to find some NGK v-power or AC Delcos