Car smokes at idle only...
Thread Starter
TECH Apprentice
Joined: Jan 2004
Posts: 380
Likes: 0
From: San Antonio, Texas
Car smokes at idle only... My car has had issues with smoking since the new motor which currently has 2500 miles on it. This nightmare has been going on for a couple of months just after getting my back up and running after a year.
It smokes at idle randomly. Seems like it smokes more when warmed up or after going WOT and then idling at a stop. No smoke whatsoever comes out when at wide open throttle or just driving around.
This is what I have done so far to troubleshoot:
Deleted the PCV system by capping all the passenger side side off and putting a breather on the passenger side valve cove, Did compression check, all numbers were close to 160, resealed the rocker arm bolts with sealant, added some "ring seal" oil additive to try to stop smoking.
I am waiting on my local shop to get their leak down test kit next week so I can do a leak down. So its coming down to bad rings, bad valve seals, or bad valve guides. The heads are 98 heads with new valve seals, but the shop that assembled them did not work on ls1s, so I'm not sure if they put the right valve seals on there.
Now if the rings are bad (not seated,gas washed) wouldn't the car smoke at WOT and at high RPMS? I really hope it is the valve seals... I do not know how many miles are on the heads so it could be possible the valve guide are bad. Can I replace the valve guide with the heads on the car?
I also heard something about 98 heads having different type of valve seals. Is this true?
It smokes at idle randomly. Seems like it smokes more when warmed up or after going WOT and then idling at a stop. No smoke whatsoever comes out when at wide open throttle or just driving around.
This is what I have done so far to troubleshoot:
Deleted the PCV system by capping all the passenger side side off and putting a breather on the passenger side valve cove, Did compression check, all numbers were close to 160, resealed the rocker arm bolts with sealant, added some "ring seal" oil additive to try to stop smoking.
I am waiting on my local shop to get their leak down test kit next week so I can do a leak down. So its coming down to bad rings, bad valve seals, or bad valve guides. The heads are 98 heads with new valve seals, but the shop that assembled them did not work on ls1s, so I'm not sure if they put the right valve seals on there.
Now if the rings are bad (not seated,gas washed) wouldn't the car smoke at WOT and at high RPMS? I really hope it is the valve seals... I do not know how many miles are on the heads so it could be possible the valve guide are bad. Can I replace the valve guide with the heads on the car?
I also heard something about 98 heads having different type of valve seals. Is this true?
TECH Addict
Joined: Dec 2001
Posts: 2,907
Likes: 1
From: Bergen County, NJ
So a couple of things:
First who built this engine - have you spoken to them?
Capping the PCV - there a three things to cap - both valve covers and the intake vacuum tube.
Additives - don't throw junk in there and possibly make the problem worse - a new engine should not smoke.
You're right - rings would smoke all teh time and especially at wot. Valve guide and PCV, cracked heads, etc. problems show up at idle and deceleration.
Vlave guide replacement reqyuire the heads to come off.
If you take them off - take them to a shop that knows what they are doing.
First who built this engine - have you spoken to them?
Capping the PCV - there a three things to cap - both valve covers and the intake vacuum tube.
Additives - don't throw junk in there and possibly make the problem worse - a new engine should not smoke.
You're right - rings would smoke all teh time and especially at wot. Valve guide and PCV, cracked heads, etc. problems show up at idle and deceleration.
Vlave guide replacement reqyuire the heads to come off.
If you take them off - take them to a shop that knows what they are doing.
