Any help would be greatly appreciated!


I have a 2000 Monte Carlo SS (3.8). Problem: As soon as I turn the engine off there’s sizzling and thick white smoke that comes from the rear of the engine. Looks almost like it is coming from where the EGR goes into the exhaust.


It does NOT smoke when it is running, just immediately after the ignition is turned off.

 

could be a coolant leak?

 

white smoke generally signals a coolant leak. You should borrow a pressure tester from the parts store . And with engine cold check for anything that could b melted/ loose

 

Has your car been sitting alot? Do you have the spark plug covers?

 

First thing-- I would like to thank all of you for your input/help!

Update:

It's definitely not coolant. I ruled it out by using a vacuum test gauge on the coolant system.

The spark plugs/wires do have the metal protector "boot shields".


I just installed new LIM gaskets, UIM gaskets, two coolant elbows, spark plugs/wires.

I see oil/fluid dripping from where the exhaust bolts together just underneath the rear cylinder bank. So...

I'm thinking...
A: While working on the LIM/UIM I accidentally loosened (by wiggling things around while working on the engine) an oil/fluid line that sits directly underneath the exhaust at the rear of the engine. There's a fitting (looks like a hydraulic fitting) that sits just under where the exhaust clamps together. So I'm hoping that it's spraying oil/fluid onto the hot exhaust after the engine is turned off. But I'm wondering why does this only happen after I turn the engine off??? Could the pressure on this line spike when the engine stops?

B: Somehow there's oil that gets dumped down the exhaust after turning the engine off. Could this happen?

Remember, I let the car come up to temp and I turn it off. 3 seconds later it sounds like I just poured a cup of oil onto a red hot pan. Sizzling and thick white smoke...

 

Okay, I found the problem... When I replaced the rear valve cover gasket, the back corner fell out of place when I lowered the cover into position. Oil was flowing down the inside of the heat shield and onto the header where it bolts to the exhaust pipe. As for the sudden sizzle and thick white smoke after turning off the ignition... I'm guessing there's a surge of oil inside the valve cover upon turning the ignition off.

BUT.... new problem My temperature gauge is not moving. I just replaced the coolant temperature sensor because the plastic connector broke and now it doesn't register.

It does not leak, but could it be that I didn't screw it in far enough? Or could it be that it's just a bad sensor?

 

It could be a bad sensor I wouldn't put my money on , check fuses, there's 2 temp sensors, 1 to turn on radiator fans and one to display temp on the dash. Take the sensor out and make sure somethings not plugging the coolant from contacting the sensor.

 

First check coolant level, then if you have a model with a bleedable system bleed it.