Smoke Then Engine Hammering
Thread Starter
Racer
Joined: Apr 2006
Posts: 443
Likes: 12
From: KITCHENER ONTARIO
Thanks For Help
The smoke was white and only at the point of ignition. While I heard the noise I did not see any additional smoke. It seemed a little loud for lifter noise.
I just started the car after sitting for 20 hours - quiet, smooth no smoke.
The oil does not look contaminated just quite dirty.
I found the comments about fuel in one of the cylinders and carbon to be very interesting.
I am going to try fresh oil and filter.
Thanks,
Rich
I just started the car after sitting for 20 hours - quiet, smooth no smoke.
The oil does not look contaminated just quite dirty.
I found the comments about fuel in one of the cylinders and carbon to be very interesting.
I am going to try fresh oil and filter.
Thanks,
Rich
Melting Slicks
Joined: Nov 2007
Posts: 2,283
Likes: 555
From: Pittsburgh PA
St. Jude Donor '10-'11-'12-'13-'14
Melting Slicks
Joined: Jul 2010
Posts: 3,001
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From: Surprise, Az
Techron is about the only mechanic in a can that I know of that actually works. If there is an injector it carbon problem, a can of techron in the tank and a trip down the freeway, hitting redline a couple of times will usually clear things up. I would do this just prior to changing the oil because the oil will pick up a lot of the carbon you just knocked off during the freeway run. If the problem persists, I would then head to the dealer.
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
White smoke is coolant. If it was fuel, the smoke would be black. You hopefully only have a bad head gasket and not a cracked head/block. The hammering meant you didn't have a lot in the cylinder and it worked it's way out quickly. It most likely broke up a bunch of carbon in the process contributing to the hammering. Look in the coolant tank for foam. If the previous shut down left the marginal cylinder with both valves closed, it may have created a vacuum when the engine cooled to suck in a small amount of coolant.
If you're under warranty, take a trip to the dealer. They'll probably do a leak down test first.
If you're under warranty, take a trip to the dealer. They'll probably do a leak down test first.
Safety Car
Joined: Nov 2006
Posts: 3,667
Likes: 159
To add to Hoxxoh's post, if it is a coolant related issue, you will lose antifreeze into either (or both) the engine oil and the exhaust. Keep tabs on your oil, to be sure it does not increase, and start to look milky (from the antifreeze). And, be careful (meaning, don't get burned with hot antifreeze), but also check as he suggests for foaming/bubbles in the coolant over flow jug. You may also be able to smell exhaust odors from the antifreeze there, if you have this issue.
Thread Starter
Racer
Joined: Apr 2006
Posts: 443
Likes: 12
From: KITCHENER ONTARIO
Great Information!
I am leaning toward the tiny amount of coolant explanation. So far everything checks out fine and runs great. Oil does not look contaminated with coolant - could be small leak just starting?
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Racer
Joined: Jul 2011
Posts: 383
Likes: 19
From: Tellico Plains TN
Modern engine management system seem to live to generate codes, so the very first thing I would do is check them if you have a gizmo to do that, or take the car to someone who can. If something that significant happened, there's a good chance there will be a code logged, which may end a lot of speculation.
Good luck,
Rusty
Good luck,
Rusty
Drifting
Joined: Apr 2008
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From: Lehigh Valley Pennsylvania
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
Be sure to explain every detail to the tech who does the leak down test. A small leak, being harder to detect, will require extra close observation of the data.
Melting Slicks
Joined: Oct 2008
Posts: 2,098
Likes: 8
From: Dayton Ohio
You may want to consider an oil analysis. If there are traces of coolant in your oil, this will tell you for sure. No guessing...and it will only cost you $25 to find out.
Team Owner
Joined: Oct 2007
Posts: 26,745
Likes: 694
From: PA
Hrm......a friend of mine had something similar. Turned out to be a weak valve spring and oil made its way in to the intake because it had a crack in it. A dropped valve can make a hammering noise which could be due to a bad valve spring.
That will not only put a hole in your piston bug also hurt the lining of the cylinder and put a hurting on your head, most likely making it junk.
I wouldnt drive it if its "hammering".
That will not only put a hole in your piston bug also hurt the lining of the cylinder and put a hurting on your head, most likely making it junk.
I wouldnt drive it if its "hammering".
Safety Car
Joined: Apr 2010
Posts: 4,231
Likes: 451
From: Maryland
I say it was a stuck valve lifter(s); for what ever reason.
Change oil/filter <(use factory) and keep an eye on your coolant level.
"If" you want take the coolant cap off before you start the car and look for continuous or regular/timed bubbles after you start it. Maybe a little over reaction going on here. IMHO
I would also run the car "HARD" up through the first two or three gears a coupe of times after the car has warmed up to blow any loose carbon, ect. out the exhaust. The car is made to do that so if something gets worse than it's covered and a good way to find it out now. Oh, and throw a bottle of techron in the fuel tank, just for the hell of it; can't hurt.
Last edited by C7/Z06 Man; Jun 11, 2013 at 05:38 PM.
Safety Car
Joined: Apr 2010
Posts: 4,231
Likes: 451
From: Maryland
DITTO!!! However just leaky would not take minutes to pump up and if leaky enough the noise would not completely go away however dirt, etc. in the lifter could of caused your problem that cleared itself.
Last edited by C7/Z06 Man; Jun 11, 2013 at 05:20 PM.
Instructor
Joined: Oct 2007
Posts: 242
Likes: 2
From: Kansas
I have had something like this 3 or 4 times. I believe it is a single collapsed lifter on the exhaust valve. It sounds like a midget inside the engine with a sledge hammer. If the exhaust valve does not open, the exhaust blasts back into the inlet and sounds like hell. It goes away after several seconds as the lifter pumps up. It does generate smoke till a correct cumbustion cycle is restored. it did not generate a code. In all cases on my 08 it was after shutting the car off cold then letting it sit for a few days. It is worse in cold weather. I now make sure the car is up to temp after a wash or a oil change. No problems in the past 2 years once I made a correlation to shutting it off cold. I don't think it hurts anything but scares the heck out of you. I have a coworker with a 08 and his has done the same thing.
Race Director
Joined: May 2008
Posts: 10,742
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From: Manheim Pennsylvania
Sounds like a lifter leaked down, after you ran the engine it pumped back up. Drive it normally, see if it happens again. I had a Corvair, the lifters were always leaking down and clattering at start up. When a lifter isn't pumped up the valve timing is off, could be the cause of the smoke.