Why would your engine smoke?

Answer 1

Smoking EngineHere are opinions and answers from FAQ Farmers:

• Your engine would smoke if you are running at too high RPM or have had your RPM at a high level before. The engine is getting overheated. When you say it only smokes until about one mile it sounds like a problem with the engine. starter.

• I would guess that its parents probably did and it learned it from its environment. More realistically, is it white smoke you see? And I would further guess that you have a 3.8 motor. If this is true, plan on a head gasket job and shave the heads. $1200 to $1400 if a shop does it. Or stress, frustration and possibly as much if you do it and it doesn't go well!

• I doubt it's the starter. You probably have bad valve guides. Oil slowly runs down your valves after the engine is off then burns away as you drive. It stops after a mile because oil pressure keeps them sealed. If you had bad rings it would always smoke or always some when you decelerate at high speeds. Closing the throttle at high speed created high vacuum in the motor and suck oil up past the rings into the combustion chamber where it burns.

• One or more oil rings are bad.

• Valve seals become brittle and need replaced at about 100,000, sooner in hot climates. Rings will also make it smoke, or raw gaz puddling in the intake manifold if carburetted, excessive crankcase pressure will force oil past the rings if the system does not have relief through the pcv valve.

• Unfortunately--That 1st answer is BAD (in this case). Overheating right at start up--Hey--On Planet Earth, engines don't overheat right at start up. Of course, physics and your temp gauge will confirm this fact. The too high RPM isn't too bad, but again, not the answer. I'm sure it smokes at low/high idle until warm. BINGO--The VALVE guys all have the right answer, in my opinion. There are other reasons it might smoke, as given, even overfilling; but from your description, it's the valve seals! They smoke when cold on start up then go away. It will get worse and worse. Budget about $400 from a mechanic that charges merciful rates.

• First of all, the only Correct answer to your question is that your valve seals/Guides need to be replaced.Oil is leaking down the valves when the engine is cold and dripping into the cylinders, thus burning off after the first mile you drive.As your engine warms up and the oil burns off, the smoke will disappear. You will have this problem after your car is sitting for a while or on cold starts. Just for knowledge, Blue smoke is burning oil. Black smoke means over fuelling or air restriction whih means to much fuel. White smoke means burning antifreeze or water which is caused by a bad head gasket. By the way, the first two answers to your questions are completely out to lunch, These people have no business answering automotive questions.

• I have a truck that does the same thing. It recently passed a CA smog test despite the huge amounts of smoke it puts out after first starting. The smoke is white but I can imagine someone describing this as "blue". The obvious reason it is smoking only after it starts was stated by the guy who said valve guide seals. Oil is pumped up to the top of the cylinder head above the valves and cylinder pressure (not oil pressure) keeps the oil from flowing down into the cylinder. When you turn the motor off it runs down into the cylinder. When you go to start it the oil burns up and comes out as smoke. My car also diesels and back fires when I shut it off. It does not run very well on oil but it will run for a while. This will cause your plugs to foul early and you will burn more oil than usual. The repair requires removal of the cylinder heads...usually. That's my 2 cents worth. The other answers are incorrect and are not even close. I admit I could be wrong but I know it's a pretty good guess...it seems several others here have the same opinion.

• I had a Mazda that lost power and would smoke a blueish whitish smoke and later started to die. Turned out a bottle of engine sealant did the trick.

• Additionally, the thumb rule is that: white smoke is usually caused by coolant water (or antifreeze) entering the combustion chamber; blue smoke is essentially due to oil (lubricants) getting in to the cylinder; and black smoke is generally because there is too much fuel (Diesel / Petrol) being inducted / injected in to the engine. And grey smoke would be due to a mixture of water and (excess) fuel entering in to the combustion chamber.