Isolated Oil Smoke Issue
Isolated Oil Smoke Issue 2004 5.3 LY7 and 4L60E in a 1978 Caprice.
I've put almost 6K miles on my engine since install. It had 12X,XXX miles on it when I installed it. I've had zero issues iwth oil smoke. It's a daily driver, and I floor it to pass a car once in a while, but no racing. I just installed new gears (2:41 to 3:42) about two weeks ago. I have driven interstate speeds before with no issue. This past Sunday I took an hour trip on the interstate at speeds between 70 and 80mph (approx 2K-2.5K RPM) for about an hour. We stopped at a restaurant for approx 45 minutes. When I got back in the car and started it a very large amount of oil smoke bellowed from the tailpipes. It didn't last long, but it was very thick and the smell was pronounced. After this, no more issues. No issues on the way home or after getting him or the next day when starting the engine. In case it is relevant, the car has true duals with no cats.
Any ideas on what may have caused this?
Thanks,
Brandon
I've put almost 6K miles on my engine since install. It had 12X,XXX miles on it when I installed it. I've had zero issues iwth oil smoke. It's a daily driver, and I floor it to pass a car once in a while, but no racing. I just installed new gears (2:41 to 3:42) about two weeks ago. I have driven interstate speeds before with no issue. This past Sunday I took an hour trip on the interstate at speeds between 70 and 80mph (approx 2K-2.5K RPM) for about an hour. We stopped at a restaurant for approx 45 minutes. When I got back in the car and started it a very large amount of oil smoke bellowed from the tailpipes. It didn't last long, but it was very thick and the smell was pronounced. After this, no more issues. No issues on the way home or after getting him or the next day when starting the engine. In case it is relevant, the car has true duals with no cats.
Any ideas on what may have caused this?
Thanks,
Brandon
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Joined: Jun 2016
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From: Central Cal.
Both pipes? There might have been oil accumulated in the heads after running a while, and your valve seals might be a bit tired. While sitting, that oil ran past the seals into the cylinders, and once fired up, BADDABING!, a smoke screen.
I'm not sure if ti was both pipes. I was in the car with the door open when I started it and it didn't last long enough for me to even walk around to the back of the car, but quite a bit came out.
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Joined: Oct 2011
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Some of the early ls's had and pcv issue , with them sucking oil from the drivers side valve cover ,next time it does it look in your throttle body , if this is an issue with your engine there will be oil on the bottom of the throlte body behind the blade .Replacing the drivers side valve cover with a newer [baffeled] model will cure this issue , as im sure a catch can would also .
The scenario you mention in your post sugests this may be the issue , as running that rpm is pulling more vacuum
The scenario you mention in your post sugests this may be the issue , as running that rpm is pulling more vacuum
Thanks for the replies. After reading these and looking I realized I never replaced the PCV valve at all. I haven't been able to look into it much at all but I don't see how that PCV valve would be removable. When you say get a newer valve cover with a baffle, what is the difference between the newer and older. I mean I know you said there is a baffle, but is it an internal baffle? Does it still have a built in PCV valve?
Thanks,
Brandon
Thanks,
Brandon
I finally was able to find this info in case it may be helpful:
This is GM's third attempt to mitigate the oil consumption issues plaguing LS1 engines and 1999-2013 LS engine trucks. For some reason the engine eats oil through the PCV setup and people who run catch cans catch a significant amount of oil. For millions of engines that don't it pools up in the intake. I was surprised when I pulled the intake manifold on my truck to see oil weeping out of the intake runner outlets.
New GM valve cover. Includes new gasket and grommets. Part number 12570427 for 2009-prior LS engines which has the hose connector barb for the PCV tubing. 12642655 is for 2010-2013 LS engines which uses a push on fitting connector.
This is GM's third attempt to mitigate the oil consumption issues plaguing LS1 engines and 1999-2013 LS engine trucks. For some reason the engine eats oil through the PCV setup and people who run catch cans catch a significant amount of oil. For millions of engines that don't it pools up in the intake. I was surprised when I pulled the intake manifold on my truck to see oil weeping out of the intake runner outlets.
New GM valve cover. Includes new gasket and grommets. Part number 12570427 for 2009-prior LS engines which has the hose connector barb for the PCV tubing. 12642655 is for 2010-2013 LS engines which uses a push on fitting connector.
