Ok guys i bought a 99Ls1 Z28 it runs great it does have a tune on it,automatic transmission with a 3000 stall converter! The problem im having is yesterday i took my daughter to the doctor the car never ran hot and does not miss at all so im heading home running it a little hard nothing mager i pulled up on my slab got out and noticed that i had water pushing out of the over flow jugg it was all the way to the top but it was not hot as i put my fingers in it it was cold antifreeze! So i let it cool all the way down went back out and the water in the over flow jugg was back down to were i couldn't see it the stick read full on cold and hot, so my next move was radiator capI opened it and the water level was perfectly fine, so what could have caused this a water burp? Also the low coolant light keeps coming on I can kill the engine turn it back on start it and it goes off,then I got to noticing that I have condensation coming out of my tail pipes I may be paranoid but I'm worried that I might have a blown head gasket but the water that comes out of the tailpipe is so clean it doesn't smell sweet I don't know what to make of thisif anyone has any input please crabby if you're out there give me a hand old buddy!!I paid a lot of money for this car I've only put 400 miles on it it would be hard for me to believe that something is really wrong with itit drives too welljust don't want to take any chances because it has an aluminum block

 

Check oil. See what it looks like. The system may have been overfilled which led to the overflow tank overflowing...though a little odd it was cold. If the oil checks out good and the temp gauge wasn't pegged, I would safely say the head gasket isn't leaking, at least not into the cylinder.

 

This test will either give you a good nights sleep, or ruin it. Either way it will let you know what you need to know.

 

ok I have checked the oil there is no water in the oil,I have not had to add any water at all,I've put maybe 500 miles on the car easy miles to not real hard ones I have ran it a few timesI do know that the car was in a accident but has been totally repairedand it was on the side where the overflow tank would beanyway I got to looking and I've seen that the radiator cap was leaking a little like seepage after running it for about 20 minutes,now my question is the guy that I bought it from put a lot of money into the car put it on the track twice never really had time to drive it because he was a copI've been driving it daily could I have sucked air in through a bad radiator cap which calls the reservoir to burp out the water?and if so would it be natural for the water to be cold I say water it was antifreeze?and after warm up the exhaust has no condensation coming out afterwards it does when you first crank it but its real clean water but completely stops after its warmed up is that normal condensation am I just paranoid because I'm having a water problem thank you guys for the info would love to hear back!!

 

would like to add that the car never ran hot still hasn't ran hot knock on wood it is not running hot that's what's freaking me out I'm hoping it's a water burp I don't know.lol.I forgot to add that

 

try a new radiator cap?

 

Got a new cap and it seems to be holding in there i guess a Leakey cap can cause some issues

 

does the water light come on,when mine I drove an for over year before I relized I had very small leak ,took all that time to notice ,so yes keep an eye on it .with mine on dry day at the end could seen small amount of conisation comeing from tail pipe,when I mine went I know now I was doing a mean burn out ,when I was done I seen the watr light come on,little did I know it went then ,,after that I was adding water ,it wouls start to get hot at lights ,not over heat ,it never did over heat ,then I changed the motor they are bullet proof but the seals not an I never had water in oil that how small the leak was ,but my fans were not comeing on at the right times either

 

Sounds like the symptom mine had just after I brought it (although it is LT1)


Radiator cap was leaking causing the coolant to overflow. Replaced cap and problem never returned. Fingers crossed that's your only issue...

 

stupid ethanol draws water from everywhere and can cause steamy exhaust at times.