I have a car with a recently rebuilt engine(800 miles) and I have been noticing that occassionally but not all the time that during start up a puff of white smoke comes out...i would say it comes out for a few seconds then stops. Ive only noticed it during start up and that is it. What's going on?
Last time I checked the oil and coolant they were just fine but ill have to check again but just wanted to know what it could be. I recently got some new alumnium heads as well and i think thats about it. Thanks !
2007-09-04 08:45:22 · 12 answers · asked by Ernesto E 1 in Cars & Transportation ➔ Maintenance & Repairs
its hot here in texas and I only see the condensation during winter..never with my car during hot days. The oil leak might be something because I have noticed a few drops of something on my driveway...not sure if its oil but it not like a puddle but maybe a spot or two...one time a saw a couple spots all over....might be the head gasket..but any more info would be great....and doesnt oil burn blue or something?
2007-09-04 08:54:31 · update #1
Valve stem seals sounds like the best answer...i have heard that from a few of my friends..How serious of a problem is this? Probably won't get a chance to take it to a shop next week or two..just wanted to know how urgent is it....if it is the valve stem seals
2007-09-04 08:57:14 · update #2
FUEL INJECTORS.
I did replace my fuel injectors...Corvette LT1 stock with 30#Ford Racing SVO injectors(best from what I have read) and maybe they are leaking. ill have to do those test but i didnt even think about that.
2007-09-04 09:00:28 · update #3
FUEL INJECTORS.
during start up and if there is a big amount of white smoke that comes out the car seems to stumble a bit...very little but I can notice it but then goes away after a few seconds.
2007-09-04 09:01:49 · update #4
Take it back while you still have warranty. White smoke means that coolant is leaking into the pistons. Given it is only during start up, I suspect it is very minor leak. Most likely the leaking coolant pools during off period and them it burns into noticeable white puff. But eventually these things get worse and worse until you have no choice but have to fix it.
By that time your warranty might have run out.
White smoke = coolant burning / leaking
blue smoke = oil burning / leaking
black smoke = dirty incomplete fuel burn (running rich)
Good Luck.
2007-09-04 08:55:30 · answer #1 · answered by Lover not a Fighter 7 · 0⤊ 0⤋
Smoke or vapor coming out the tail pipe is caused by three things. First, normal condensation, especially when it's cold. This is normally white, and dissipates quickly, and is steam, not smoke. Then, oil smoke, which is bluish, which can happen when you first start the car because leaking valve seals allow oil to seep into the cylinders and burn off on startup, and also for a few minutes oil may get past the rings before the engine heats up and the clearance between the pistons and the cylinder walls closes up. Third, poorly-burned fuel or an overly-rich air-fuel mixture. This is normally black or brown. Neither oil smoke or poorly-burned fuel smoke dissipates, they hang in the air. A thick combination of white, blue, and possibly brown is an indication of a blown head gasket or a cracked block or head, and is a combination of water, oil, antifreeze, and normal exhaust that are dumping out the tail pipe. This would cause a noticable loss of coolant and oil. personally, I wouldn't worry about it if you are seeing no loss of coolant or oil. Check your oil frequently and make sure it looks like oil and not a frothy chocolate malt. Coolant in the oil will make it look brown and frothy. Also, when the engine is cold, (so you don't burn yourself), take the radiator cap off, start the car, and seal your palm over the opening. If you feel a pulsation, you may have a compression leak indicating a blown head gasket or cracked block or head. If everything checks out, no water in the oil, no oil or coolant loss, and no pulsation during the palm-on-the-radiator check, then I would think what you are seeing is normal condensation that is caused when hot exhaust hits a cold exhaust system, and maybe a bit of oil burnoff.
2007-09-04 09:08:00 · answer #2 · answered by Me again 6 · 0⤊ 0⤋
If the headgasket were leaking, the problem would not be just in startup. White smoke can mean coolant, but it can also mean unburnt fuel. Usually, for fuel, you look for black smoke, but if there is enough that it gets through unburnt, you don't just have a rich mixture, you have a little liquid fuel getting into the exhaust. That manifests as white smoke.
My first suspect would be leaky fuel injector(s). If they drip when the car is sitting, when you start it up, you'll have to burn that fuel off. It might run a little rough as well. If you have a port to test, test the fuel pressure (testers are cheap at auto parts stores). You should be able to start the car, shut it off, and the pressure should not bleed down...especially not quickly. If it does, you have an injector issue, or possible fuel pressure regulator/fuel pump, but given the smoke, I'd suspect the injectors.
If any of this is more than you want to tackle, I would ask a trustworthy mechanic (I must emphasize this, as injectors are not cheap) to test the fuel pressure and whatever else he/she suspects. If you are careful (extra careful if you have a high-energy ignition), you can pull one spark plug wire off the distributor at a time, and trace the wire... If the engine smoothes out after doing so, you can at least narrow it down to which cylinder(s) are the problem.
Hmm, I suppose it may also be condensation as the person above stated...but I would kinda doubt it if you don't have somewhat cold weather.
2007-09-04 08:54:46 · answer #3 · answered by messenger_of_the_void 2 · 0⤊ 1⤋
Recent replacement of aluminum heads and the presence of white smoke is indicative of a warped head and or leaking head gasket. The fact that it is a small leak is evidenced by the fact that just a puff occurs at start-up. Aluminum is notoriously fickle. Over tightening or undertightening the head bolts could cause the problem, as could poor machining of the heads. The difference in expansion of dis-similar metals will be evident in hot climates. The fact that the coolent level is OK doesnt mean theres no loss, especially if its only a few ounces per week. All indicators point somewhere. These point to coolant leaking into cylinders.
2007-09-04 09:05:14 · answer #4 · answered by davidosterberg1 6 · 0⤊ 0⤋
You have left off important information. But here is an answer for common problems. Valve seals, a burst of smoke at start up means oil is escaping through the stem of the valve inside the head. Once the engine heats up, the expansion seals it off. Leaking valve seats on the bell end of the valve can let oil into the exhaust side of the head. The heat naturally turns it into smoke. That is what you are seeing. As long as it stops and doesn't continue during driving, just monitor your oil. Chevy V8 engines are notorious for this.
2007-09-04 09:02:09 · answer #5 · answered by Eric S 2 · 0⤊ 0⤋
Diesel White Smoke On Startup
2016-12-17 12:43:31 · answer #6 · answered by buena 4 · 0⤊ 0⤋
This may sound weird, but do you park in a particularly dirty location? Perhaps one with trees? I have noticed that sometimes things can get on top of the engine and burn up, causing smoke for a few seconds.
Also, check your battery for leaks.
2007-09-04 08:49:41 · answer #7 · answered by Esma 6 · 0⤊ 1⤋
Valve stem seals are allowing something to run down after engine shut off.
2007-09-04 08:54:15 · answer #8 · answered by jimmymae2000 7 · 1⤊ 0⤋
If it is run on a carburetor instead of fuel injection the mixture may be to lean.
2007-09-04 08:51:41 · answer #9 · answered by Pat 5 · 0⤊ 2⤋
Check the head gasket, it may be leaking
2007-09-04 08:48:24 · answer #10 · answered by Anonymous · 0⤊ 1⤋