white smoke

Hi there,
thank you for the donation.

You may have a small coolant leak that is not visible, have a coolant system pressure test done as this will show up any small external leaks, also have a head check done, this will detect any exhaust gasses in the cooling system, this is a sure sign of head problems, with the engine oil it is normal for the pressure to drop when the engine heats up as the oil gets hot it looses some of its viscosity and the pressure will fall little at idle, if you keep your engine services up to date this will not be a concern for some time to come.

mark (mhpautos)

hate to say it you have the same problem i had i spent almost 5k to get it fixed. GM has a service builtten out on the o4 yukon. the head on your yukon are basicly JUNK. the problem is the casting of the heads were bad and the antifreeze is going though the metal in the head. i know it sounds funny but its the truth i saw it with my own eyes. we had the heads redone in December and the dealer in Michigan didnt bother telling us about the service bulliten. then i got down to texas and not even 4 months later the antifreeze was mixing with the coolant. witch is what is happing to you. my wife had the white smoke on start up problem. as well the head gaskets are what they said were bad the first time but. now after having it fix with new heads things look pretty good so far. hope this helps. you can expect to see more problems with gm. i use to work for a suppler of gm and saw the stuff our plant in mexico was making and it sceard the hell out of me to see the stuff they were sending out. so i will say i will not buy gm any more gotten burned to many times i think i am going to be a ford man now.

alos dont waste your money on having it pressure checked with out taking it to the dealer and telling them you know about the bulliten and you want to know if these are the heads on the bulliten witch sounds like they are there is a casting mark that identifes the head. your best bet is just to replace the heads!!!!! other wise you will be wasting money like i had too. good luck let me know what happens. hope this helps

also check you oil if it looks like a light brown and is milky. your heads are the problem. thats how i cought it the last time. i was close to an oil change and it looked light brown not dark and i had to add 3/4 of a gallon. you can also pull off the oil filler neck by twisting it and looking in side of it for oil and antifrezze mixing by thick guuey stuff.
hope this helps
just pissed at gm a little over crappy quailty again.

Hello there I just want to know what could be causing the light vibrations in my engine? I just bought it like 3 weeks ago with no problems, no oil leaking, great power, ran great,no over heating ect everything was working fine until 08-26-08, In the morning I felt the little vibration but still ran good,then later in the day the service engine light came on and everytime I slowed down the I felt the vibrations a little more,but then later on the day my girlfriend noticed like a gas smell or something,well anyways when I was at a stop light and I press on the gas pedle a little white smoke came out but dessapeard when I speed up,I noticed the smoke a little more when I stop then go, but all of sudden I didnt see no more white smoke but still felt the vibrations, with no overheating at all, what could it be? could be something serious? do u recommend I still drive it? please help

you can drive it, wouldnt go to far and i would cary a cell phone.

get the vehicle scanned for codes since hte light is on. it will help narrow down the problem. post it back!

ok, i bought a 1989 GMC Suburban for $300 from a guy i know, at first it was missing, so i changed spark plugs and wires. Then it was leaking antifreeze, so i changed my water pump, then noticed when changing it that it wasn't the water pump that was leaking, but instead it was my radiator. So i replaced the radiator. Now there's no leak, but now white smoke just ROLLS out of the exhaust and tends to overheat, im guessing its antifreeze leaking into the exhaust somehow. It also runs kinda rough like it doesn't act like it wants to stay running when ideling. Any suggestions?

you are dealing with a blown haed gasket. the antifreez is entering the combustion chamber that is your white smoke. that will also couse the overheating problem. exhust gasses are entering you cooling system creating air pockets so the coolent does not flow properly

2003 Chevy Malibu overheated Changed themostat had it flushed and still overheated. replaced thermostat again and ECT sensor. Now white smoke out of exhaust and rough idling and check engine light on

White smoke usually indicates coolant is getting into the combustion chamber. Most likely, it is a bad head gasket.