akataria

Hello,
I have 2001 LS430 with 106k miles on it. This morning all of a sudden I heard knocking sound under the hood and lots of white smoke coming from the exhaust. I turned off the car immediately and am planning to towe it to a garage in a couple of days. Any ideas on what it might be. How serious might it be etc?

Thanks for the advice.

Regards,
-Al

GLIDESUL

Sorry to hear you problem. That's a first on here for me. I had that problem before and my car was misfiring bad it turned being a tune up plugs and wires but that was a cressida years ago. Maybe you can check under the hood to see if everythings looks ok. Hope u get it back right.

DaveGS4

iTrader: (2)

White smoke from the exhaust often means head gasket issues.

Did you check your fluid levels (oil and coolant)?

caddyowner

Have your timing belt and water pump been changed?

Jabberwock

White smoke from exhaust is a bad sign - almost always means water getting into the combustion chamber. Like Dave posted most common cause of coolant getting into exhaust is a failed head gasket that allows the pressurized coolant to get past the failed gasket and into the combustion chamber.

The knocking is likely pistons hitting the steam/water mixture in cylinder although it could be something more serious like a broken connecting rod.

Head gaskets can fail and leak due to severe engine overheating caused by broken water pump, radiator fan failure, or running the car with very low coolant. Hopefully that is not your situation because it usually means the motor is cooked.

If you have a simple head gasket leak and caught it early (not letting the motor overheat) you may be able to have the head gasket replaced without additional motor work.

Make sure coolant and oil is totally flushed and refilled if head gasket is replaced because both are likely contaminated with the other fluid at this point.

scottgolf

back in my racing days, we used to call this the milkshake. you could pull out the dipstick, and it looked like a milkshake with all the coolant mixing with the oil pan.

this doesn't seem typical for an ls with only 100k, this is more of an american car thing. but you have all the tell tail signs of a milkshake. I don't know some people fix the motors, but I haven't had good luck with that so. once I milkshake a motor its gone. in one of my race cars I had one fixed and it cost me almost as much as a new motor so i never did that again.

this is very common with the crappy northstar motor

JLAWS

Yeah my elderly neighbor across the street had his headgasket go on his mint 2002 Cadillac Deville. Its been parked in the same position for 5 month.

Bon

Power steering / transmission fluid also burns white. I once had a vacuum diaphragm get a pinhole leak and allowed transmission fluid to be sucked into the engine. It created a huge white cloud. There is such a vacuum device on the power steering pump I believe that modulates assist levels. Don't know about the transmission.

Anyone know about brake fluid? Vacuum assist power brakes?