Smoke on Deceleration
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Smoke on Deceleration Hey Guys -
I am having trouble with my 2000 SS LS1 with smoking (I believe burning oil) on deceleration. It's a mostly stock vehicle with 74k miles on it.
I noticed no issue on it when completely stock (up until 72k miles or so) nor when I swapped an LS6 intake onto it. Late last summer, I ended up upgrading to the Hooker TD system, and this is when I noticed the issue. I assume the stock cats were mitigating the problem.
I notice anytime I get on it relatively heavily, a few seconds after letting off I get a puff of smoke, and it smells like oil really strongly. I've added a homebrew catch can (with media in it, I really tried to mimic the good aftermarket cans) and notice no difference with it connected or not.
It also does this when on the dyno - so it's not like oil is sloshing around somewhere. I did have some light oil buildup in the stock LS1 intake, but nothing alarming at all after 72kish miles of driving - it really looked decent to me. I also don't notice it consuming oil drastically or anything. When I hooked up the catch can, I also put in a glass fuel filter. I see a little oil vapor coming through, but I don't see anything that would cause something like this. I am not ruling out the possibility of it being PCV driven, but I don't think it is.
The video below is a good representation of what's happening. The car was on the dyno, and right before the 40 second mark when the operator lets off, watch the driver's side exhaust tip. A few seconds later, watch the passenger.
Any thoughts or experience with something like this?
I am having trouble with my 2000 SS LS1 with smoking (I believe burning oil) on deceleration. It's a mostly stock vehicle with 74k miles on it.
I noticed no issue on it when completely stock (up until 72k miles or so) nor when I swapped an LS6 intake onto it. Late last summer, I ended up upgrading to the Hooker TD system, and this is when I noticed the issue. I assume the stock cats were mitigating the problem.
I notice anytime I get on it relatively heavily, a few seconds after letting off I get a puff of smoke, and it smells like oil really strongly. I've added a homebrew catch can (with media in it, I really tried to mimic the good aftermarket cans) and notice no difference with it connected or not.
It also does this when on the dyno - so it's not like oil is sloshing around somewhere. I did have some light oil buildup in the stock LS1 intake, but nothing alarming at all after 72kish miles of driving - it really looked decent to me. I also don't notice it consuming oil drastically or anything. When I hooked up the catch can, I also put in a glass fuel filter. I see a little oil vapor coming through, but I don't see anything that would cause something like this. I am not ruling out the possibility of it being PCV driven, but I don't think it is.
The video below is a good representation of what's happening. The car was on the dyno, and right before the 40 second mark when the operator lets off, watch the driver's side exhaust tip. A few seconds later, watch the passenger.
Any thoughts or experience with something like this?
Last edited by Atrus_SS; Mar 16, 2017 at 08:32 AM.
im no expert mechanic however when that happened in the old days it was oil coming down the valves past the value seats (i think) so my first thought is time for a valve job or new ls6 heads!
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That was one of my thoughts - I am hoping it's valve seals rather than something internal. I thought seals could be replaced on the car, so sounds like a cam swap would be a perfect time to fix this issue
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I have, and I actually completely bypassed the PCV (temporarily disconnected the line and plugged the port to avoid a vacuum leak) and I still got the same result.
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I have this same issue with mine (2001 camaro SS 73k miles) is on hard acceleration and deceleration . It blows out smoke. Buddies told me blue smoke as well. Few people told me it's my valve seals. I to believe this is your problem.
Smoke upon deceleration or cold start up is usually valve seals.
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Thanks for the replies, everyone - I feel much better now at least knowing it's nothing too critical and I can enjoy the car this summer.
To the OP, sorry for bringing this back from the dead. I recently had my car dynotune'd and noticed the same blue smoke coming from the exhaust. Would like to hear from some people who experienced this but with new valve stem seals. I'm also running a mighty mouse catch can setup. Could the hoses be routed wrong?