Engine Braking = Blue Smoke
Whatever I did made it worse... I was blowing smoke almost all the way to work today... full throttle nothing but under light load low rpm (under 2K) there was a cloud coming out behind me. Guess I better start planning a rebuild.
first dont engine brake.
Its likely sucking in oil from the pcv. When I changed the intake on my old camaro, it was drenched in oil. It is a common issue for these engines. Removing the pcv and replacing with a breather is the best way to do. People have used catch cans but they dont seem to catch oll the oil.
I would check this before checking the valves, rings, etc
Its likely sucking in oil from the pcv. When I changed the intake on my old camaro, it was drenched in oil. It is a common issue for these engines. Removing the pcv and replacing with a breather is the best way to do. People have used catch cans but they dont seem to catch oll the oil.
I would check this before checking the valves, rings, etc
perform a test with the PCV disconnected, it sounds like you're pulling oil through there due to the high vacuum. If it still does it then its the valve seals, due to the high vacuum pulling oil through the seals
Update: replaced plug wires and smoke issue seems to be gone. One wire was completely fubar and no longer clicking onto the plug. Might be a combination here, I'm going to back off the decel and replace the valve seals. As of right now the issue seems to be gone, not sure a dead cylinder would have done this.
What your experiencing is typical with worn guides and/or bad seals and likely both.
Engine braking creates the highest manifold vacuum and will pull oil down the worn guide (that has excessive clearance now) and ultimately into the combustion process.
A dead cylinder might smoke a little as well....hopefully that's your issue, but in the event its not I would consider a cylinder head rebuild if your trying to eliminate the smoking issue your experiencing (frankly I would freshen the whole engine at that point).
A smoking engine due to ring seal issues would be more prevalent at WOT because the higher cylinder and crankcase pressures tend to force oil past the rings (and once again into the combustion process).
Good luck.....hopefully its your (potential) dead cylinder causing the problem.
-Tony
Engine braking creates the highest manifold vacuum and will pull oil down the worn guide (that has excessive clearance now) and ultimately into the combustion process.
A dead cylinder might smoke a little as well....hopefully that's your issue, but in the event its not I would consider a cylinder head rebuild if your trying to eliminate the smoking issue your experiencing (frankly I would freshen the whole engine at that point).
A smoking engine due to ring seal issues would be more prevalent at WOT because the higher cylinder and crankcase pressures tend to force oil past the rings (and once again into the combustion process).
Good luck.....hopefully its your (potential) dead cylinder causing the problem.
-Tony
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Verdad Gallardo did you at least try a breather?
also, check the intake behind the tb. Mine had pools of oil in it. It would probably smoke with a breather until all the oil is sucked out of the intake.
Check out the profile pic of TonyM, it has a breather
also, check the intake behind the tb. Mine had pools of oil in it. It would probably smoke with a breather until all the oil is sucked out of the intake.
Check out the profile pic of TonyM, it has a breather
Teching In
Joined: Nov 2007
Posts: 27
Likes: 0
From: Buffalo, NY
Just for comparison, my 99T/A with 45,000 miles has around 210-220psi when I do dry compression tests. When I changed my rockers, pushrods and springs, the compression was down a little, and re-adjusting the rockers ensured the valves were closing properly and helped with the compression readings.
Staging Lane
Joined: Mar 2012
Posts: 86
Likes: 0
From: Columbus
I think you're being paranoid at this point. Good to hear you abuse your engine that much and your compression is still within limits. I would avoid engine braking man at all costs its really hard on your transmission and like people above have said brakes are alot cheaper than an engine/tranny.
Whats your plug gap btw? It looked excessive on #7 Cylinder.
For future reference if you do have low compression You can sometimes hear the leak through the dipstick tube if its a comp. ring, and through the throttle body if its an intake valve. And on aircraft engines you can hear it through the exhaust, doubtfully on a car though.
Using seafoam does help on engines that have been neglected of routine oil changes. It will clean up rings to allow them to properly expand and restore compression.
Whats your plug gap btw? It looked excessive on #7 Cylinder.
For future reference if you do have low compression You can sometimes hear the leak through the dipstick tube if its a comp. ring, and through the throttle body if its an intake valve. And on aircraft engines you can hear it through the exhaust, doubtfully on a car though.
Using seafoam does help on engines that have been neglected of routine oil changes. It will clean up rings to allow them to properly expand and restore compression.
I think you're being paranoid at this point. Good to hear you abuse your engine that much and your compression is still within limits. I would avoid engine braking man at all costs its really hard on your transmission and like people above have said brakes are alot cheaper than an engine/tranny.
Whats your plug gap btw? It looked excessive on #7 Cylinder.
For future reference if you do have low compression You can sometimes hear the leak through the dipstick tube if its a comp. ring, and through the throttle body if its an intake valve. And on aircraft engines you can hear it through the exhaust, doubtfully on a car though.
Using seafoam does help on engines that have been neglected of routine oil changes. It will clean up rings to allow them to properly expand and restore compression.
Whats your plug gap btw? It looked excessive on #7 Cylinder.
For future reference if you do have low compression You can sometimes hear the leak through the dipstick tube if its a comp. ring, and through the throttle body if its an intake valve. And on aircraft engines you can hear it through the exhaust, doubtfully on a car though.
Using seafoam does help on engines that have been neglected of routine oil changes. It will clean up rings to allow them to properly expand and restore compression.
Thanks for the tips... car seems to be running 'normal' again I just need to relax I think.
Staging Lane
Joined: Apr 2009
Posts: 67
Likes: 0
From: TEXAS
Did u ever figure out what it was im going through the same problem right now but my car only smokes after you've driven it for 5 mins and come to a complete stop u can see smokes come out from under hood when im at the stop light car only has 130k its an 01 ws6 with mobile 1 oil I REPLACED the pvc, my hose was cracked by the intake in the back i put tape over the crack though idk if its that.
Did u ever figure out what it was im going through the same problem right now but my car only smokes after you've driven it for 5 mins and come to a complete stop u can see smokes come out from under hood when im at the stop light car only has 130k its an 01 ws6 with mobile 1 oil I REPLACED the pvc, my hose was cracked by the intake in the back i put tape over the crack though idk if its that.
Good luck with your issue...
Since Ive posted last in this thread, I did a head swap on my car. Also had blue smoke while engine braking. Although it was very little smoke, the valve guides where the problem. The intake valves were wet when disassembled and all the guides had carbon build up under the valve seal. That would be a good check on your car is to pull a couple seals and see if it looks like mine. I did not do a compression check before pulling the heads but I did early last year before it started smoking.
