decelerating at high rpms..smoke issue
#1
TECH Apprentice
Thread Starter
iTrader: (4)
Join Date: Feb 2006
Location: Md.
Posts: 398
Likes: 0
Received 0 Likes
on
0 Posts
decelerating at high rpms..smoke issue
Was driving,& i noticed in 3rd gear and 4th at 6 to 7k rpm's of course high speeds i am spraying blueish smoke from out the exhaust only when i decelerate....My last tunner disconnected the catch can and took off a resonator that comes off the headers so i am running straight pipes to my Borla mufflers on my vette...no smoke on acceleration just when i take it up to say 7k then let off the gas any suggestions or link to this problem..thanks
#3
TECH Apprentice
Thread Starter
iTrader: (4)
Join Date: Feb 2006
Location: Md.
Posts: 398
Likes: 0
Received 0 Likes
on
0 Posts
deceleration smoke
I have been running catless for 5yrs...and no problem till lately...My last oil change it seemed to have started and is now progressing....wondering the pure synthetic 10w/30 could be causing it....thinking about going back to conventional Penzoil 10w/30.....
#4
On The Tree
Join Date: Sep 2008
Location: Virgina Beach
Posts: 180
Likes: 0
Received 0 Likes
on
0 Posts
I'm guessing you have an LS1 Corvette? If that's the case your just seeing the crappy LS1 PCV system in action. I road race my LS1 trans am and have delt with that for the past few years. I can get it to the point that people come up to me after a session and ask me if I blew my motor. An oil catch can/seperator will help but not fix the problem. There is a good write up on LS1howto about switching over to the LS6 PCV system. That's going to be the only real way to fix the issue. It's not going to matter what type of oil, but if you use a thicker weight it will smoke a little less. The only thing it's affecting right now is you spark plugs. So don't worry too much. You'll learn to ignore it.
#5
TECH Apprentice
Thread Starter
iTrader: (4)
Join Date: Feb 2006
Location: Md.
Posts: 398
Likes: 0
Received 0 Likes
on
0 Posts
I'm guessing you have an LS1 Corvette? If that's the case your just seeing the crappy LS1 PCV system in action. I road race my LS1 trans am and have delt with that for the past few years. I can get it to the point that people come up to me after a session and ask me if I blew my motor. An oil catch can/seperator will help but not fix the problem. There is a good write up on LS1howto about switching over to the LS6 PCV system. That's going to be the only real way to fix the issue. It's not going to matter what type of oil, but if you use a thicker weight it will smoke a little less. The only thing it's affecting right now is you spark plugs. So don't worry too much. You'll learn to ignore it.
#7
Worn (intake mostly) valve seals are usually the cause of startup puffs of smoke, and decel smoke. When you close the throttle at high rpm's, theres a lot of vacuum created in the intake tract, and pulls hard on the valve seals as well, sucks some oil, and presta - smoke machine!
Oil causes detonation, so stopping your engine from burning it should be a priority.
The ls6 pcv is a great idea for these engines, with how isolated the "lifter valley" is from moving/rotating parts coming in contact with oil.
Oil causes detonation, so stopping your engine from burning it should be a priority.
The ls6 pcv is a great idea for these engines, with how isolated the "lifter valley" is from moving/rotating parts coming in contact with oil.