running on three cylinders..help plz...

[cencal180]

Im trying to help a friend out with his red top SR. his SR is running on three cylinders. we check the coilpacks..the spark plugs..some of the wiring. from what he told me, one day it blew a big clowd of white smoke. it did it tiwce then stopped. im guessing neither is was burning oil for a sec or his head gasket is parcialy blown? he has no signs of over heating. i still needa do a compression test to. as for now any ideas? thnxs for any replys/help!

[spoonman]

sounds like a blown head gasket, but could be anything. did you change the plugs or just check them?

[cencal180]

he changed the plugs a week before it happend.

[koukimonster139]

check oil for coolant or vice versa.

sounds like a HG. a partial blowout or small blowout probably wouldnt make it overheat

[cencal180]

yea, i was kinda guessing it was a blown HG. thnxs for the replys guys.

[zugoi]

Sounds like the headgasket to me as well. If you do a compression test tho and it says other wise. Try a cylinder leak down test.

[Wei240]

if it idles funny, it could also be blown rings..
only way to find out for sure, is to do both compression AND leakdown

[zugoi]

Well you dont need to do both. Just do the leakdown and it should tell you weather its the hg or pistons or valves etc. Just make sure its tdc before u do the test.