Well the other night after work did a lil burnout and my co-worker noticed i was blowing a lot of white smoke out the exhaust. I've been having an idle issue for a few months now and I suspect that a Head Gasket Leak could be the problem. How can i go about checking this? just spray some starter fluid around/by the gasket its self and see if the rpms go nuts if theres a leak or what?


i watch my afr on my aem go from 12.0-17.0 when its idling funny so it has to be head gasket leak, intake mani gasket leak, or a vaccum leak.

smells like i'm running race gas all the time also if that indicates anything.

throwing a random misfire in all cylinders. only at idle can you hear it and smell it above idle she runs like a champ

and around the snout of the blower, well actually closer to the block theres a funky little noise like something ratteling or catching on somthing

did a compression test and 160's across the board

 

ive always had an idle fluctuation problem... both with the stock tb and alsowith the ls4 tb. usually just a quick rev will get it to "reset" and hold at the set rpm (which is set to 900 instead of 850)

if you find out if it's a boost or vacuum leak, please post. i've checked and rechecked all my hoses and connections and have found nothing yet

 

you cant check for a head gasket leak from the outside. unless its an external leak.

you want to pressure test your cooling system. let the tester sit on there for a while. a couple hours or so. pump it to 1 pound over the max cap pressure.

then start your car and watch the tailpipe. if you see white smoke and it runs rough then thats it.

the other way is to do a leakdown test. but you need some tools to do that. or they have a tool thats like a glass cylinder, you put a fluid in it. then you fit it where your radiator cap goes. if the fluid turns colors then its a bad head gasket.

the easiest way is with the pressure tester.

did you check the oil to see if you have a fluid mix ???