Smoke
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Joined: Jul 2007
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Smoke
I have a 96 with 60000 miles on it and sometimes when I crank it a light grey to white smoke comes out of the exhaust. I think white is gas and grey to black is oil. If so, what could be the problem? I am getting @22 MPG with mixed driving every day shows no oil is being burn off. Also, I have an after market radio and where the average milage is displayed it wil go away and display "SYS" for about 5 seconds and then display the average miles. I was told from the person I purchased the car that it is searching for the radio and it is not a problem. Anyone have the SYS problem and any Idea about the smoke??
Heel & Toe
Joined: Jan 2007
Posts: 19
Likes: 0
From: Onalaska Texas
Obviously, the radio and smoke problems are unrelated, and I have no clue about the radio problem. I have an aftermarket one and haven't had any problems.
As for the smoke, it is probably a fuel related problem. It doesn't sound like anything too major. I've seen/heard of some fuel management problems in L98s that cause smoking. Check and see if your car is running lean or rich.
And I guess while we're on the subject-
I've been having some smoke problems too, mine much more troublesome. (1989)
I recently had my motor rebuilt and I now have thick blue smoke billowing out of my exhaust during startup, while accelerating, and sometimes even while idling. There is oily residue on my exhaust tips. My cat is gutted, but I don't think it has much to do with it.
I haven't been able to get ahold of the guy who did the rebuild yet to ask what could be going on and what he may or may not have replaced (valves, rings, etc.). It is a 3rd party thing. I'm gonna try to get ahold of him, but does anybody have any suggestions or solutions?
As for the smoke, it is probably a fuel related problem. It doesn't sound like anything too major. I've seen/heard of some fuel management problems in L98s that cause smoking. Check and see if your car is running lean or rich.
And I guess while we're on the subject-
I've been having some smoke problems too, mine much more troublesome. (1989)
I recently had my motor rebuilt and I now have thick blue smoke billowing out of my exhaust during startup, while accelerating, and sometimes even while idling. There is oily residue on my exhaust tips. My cat is gutted, but I don't think it has much to do with it.
I haven't been able to get ahold of the guy who did the rebuild yet to ask what could be going on and what he may or may not have replaced (valves, rings, etc.). It is a 3rd party thing. I'm gonna try to get ahold of him, but does anybody have any suggestions or solutions?
Drifting
Joined: Aug 2006
Posts: 1,624
Likes: 2
From: Canandaigua New York
Don't know about the SYS problem, but the gray smoke is blow by from the valve seals.
Could be worn a bit, but if all you are getting is just a slight 'puff' on start up I wouldn't worry much about it.
If it really bugs you, then you could install new valve seals.
Could be worn a bit, but if all you are getting is just a slight 'puff' on start up I wouldn't worry much about it.
If it really bugs you, then you could install new valve seals.
Instructor
Joined: Aug 2007
Posts: 212
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From: www.C4guru.com Everywhere!
A slight puff on startup is probably condensation if the car has been sitting over night depending on the weather. Mine does that on cold nights or if its been raining really bad. If its not alot or doesn't have a sweet smell, then I wouldn't worry but you might be more of a perfectionist.
Pro
Joined: Nov 2005
Posts: 536
Likes: 0
From: Bardstown Kentucky
I have a 96 with 60000 miles on it and sometimes when I crank it a light grey to white smoke comes out of the exhaust. I think white is gas and grey to black is oil. If so, what could be the problem? I am getting @22 MPG with mixed driving every day shows no oil is being burn off. Also, I have an after market radio and where the average milage is displayed it wil go away and display "SYS" for about 5 seconds and then display the average miles. I was told from the person I purchased the car that it is searching for the radio and it is not a problem. Anyone have the SYS problem and any Idea about the smoke??
Heel & Toe
Joined: Jan 2007
Posts: 19
Likes: 0
From: Onalaska Texas
It's a lot of smoke. And it usually doesn't do it during initial startup, mostly only when warm. I saw my car driven by someone else and that's when I REALLY noticed how much smoke was coming out. It's a dark blue and it's relative to how much throttle it's given.
Thread Starter
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Joined: Jul 2007
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thanks
I noticed it one time after it sat for a few days, but what really got me was yesterday I stopped after driving for ~30 miles, spent 5 minutes in a store, and when I cranked it a single big puff of white smoke was seen in my rear view mirror. I got out and could see nothing. Got back in, revved the engine, and again nothing. This morning I stuck my arm in and cranked it and walked to the back and nothing. Not worried now, but wondering if something I should be looking for. Other than pulling the plugs and looking, is there another way to check if it is running lean?
I thought the SYS thing would be harder and will start a new thread with distinct title so maybe someone will recognize.
THANKS!!!
I thought the SYS thing would be harder and will start a new thread with distinct title so maybe someone will recognize.
THANKS!!!
Instructor
Joined: Mar 2004
Posts: 145
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From: North Shore MA
White smoke = Moisture either from coolant getting into the engine by a cracked block or head gasket blown
Blue Smoke = Oil getting into the cylinders either by passing the piston rings or the valve seals or both
Neither one is good, especially if you get it more after the car warms up.
Blue Smoke = Oil getting into the cylinders either by passing the piston rings or the valve seals or both
Neither one is good, especially if you get it more after the car warms up.
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Had to replace mine at about 70,000 miles as do most folks.
Race Director
Joined: Mar 2006
Posts: 11,628
Likes: 1
From: Sherwood, Arkansas
The "SYS" that is a result of the aftermarket stereo install is common. You need to add a couple of resistors to your wiring to fix it. Here is the fix courtesty of JEFNLSA:
http://forums.corvetteforum.com/show...58&postcount=7
Here is the TSB regarding the stereo/SYS condition:
http://www.corvetteforum.net/c4/dave8476/index4.shtml
I just noticed you said that the car was a 96 but I bet you are having the same issue many 90-93's had.
http://forums.corvetteforum.com/show...58&postcount=7
Here is the TSB regarding the stereo/SYS condition:
http://www.corvetteforum.net/c4/dave8476/index4.shtml
I just noticed you said that the car was a 96 but I bet you are having the same issue many 90-93's had.
Last edited by NEVRL8T; May 30, 2008 at 10:42 AM.
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
A short heavy blue smoke cloud at start-up is valve stem seals.
Blue smoke all day long is piston rings. If this is the case, change oil to 20 -50 til you get it fixed. Less oil will find it's way to your exhaust if it's heavier, and you won't foul your exhaust system. OR the EGR, which goes back through the intake.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
The "SYS" that is a result of the aftermarket stereo install is common. You need to add a couple of resistors to your wiring to fix it. Here is the fix courtesty of JEFNLSA:
http://forums.corvetteforum.com/show...58&postcount=7
Here is the TSB regarding the stereo/SYS condition:
http://www.corvetteforum.net/c4/dave8476/index4.shtml
I just noticed you said that the car was a 96 but I bet you are having the same issue many 90-93's had.
http://forums.corvetteforum.com/show...58&postcount=7
Here is the TSB regarding the stereo/SYS condition:
http://www.corvetteforum.net/c4/dave8476/index4.shtml
I just noticed you said that the car was a 96 but I bet you are having the same issue many 90-93's had.
Yes, the radio wiring needs two resistors added to cure the SYS light flashing on your 96.
Jake