I recently (about 500 miles ago) had a valve job done to my 90 LS Automatic Turbo Teg. I did the valve job because I needed to pull the head off to change a blown head gasket.
Since I changed the head gasket I haven’t gone over 3K RPM’s and have not run positive boost (basically I’m breaking in the re-done head). The car runs absolutely perfectly, TOTALLY smooth and ALL power is there, instant response.
My problem is when the car sits over night and then I start her up I get some white smoke if I let it sit at idle running cold it keeps smoking. (I’m fairly certain this in NOT vapor as it is quite a bit of smoke and will do it constant for too long) I’ve let it sit runnig up to 2-3 minutes and it smokes the whole time. Soon as I put her in drive and drive away it stops. If I start her and drive right away it doesn’t happen at all. Seems to only happen if I let it sit running idle cold. Basically it DOES NOT happen once I am driving and won’t happen again all day… once the car is warmed up it does not happen all day even when I let it sit during the day. Only if the car is totally cold does this happen.
As I said the head gasket is brand new and so is the valve job. What could be causing this smoke???
The car is running SOOO well that I really don’t want to mess with it. BUT this smoke is my ONLY problem and I’d like to try and fix it.
I have only a few ideas…
I have noticed that I am only getting about 250 miles per tank. I’m used to about 300…could a bad O2 sensor cause this smoke??
When I pulled the head off I cleaned some soot (a tiny layer of black) on the cylinder walls. Maybe since I removed this soot the rings aren’t sealing up against the walls as well??? If this was the problem wouldn’t I be seeing black smoke not white???
My cold start idle also is a bit too high. Not sure if this higher revving (which drops to normal once the car is at temp) could cause this?? I know at cold start it is supposed to rev a bit higher than normal but mine is extra high.
Those are pretty much the only things I can think of. ANY other ideas at all???
I’ve included a few more details about my Teg below just in case. I really appreciate ALL input!! THANKS
-My Teg has 130,000 orig miles and I am the original owner. I Turbo’d the car in 1993 when it had 50,000 miles. The car has had all maintanance including oil every 3K miles. The motor really is stock besides the turbo system and full 2.5" exhaust. I do NOT drive this car hard at all and DO NOT race it. The turbo never runs higher than 6 psi. I really have had NO problems at all with this car for all 12 years or so of my ownership (about 9 of which have been TURBO). The only problem I’ve had is this head gasket which I just replaced. Again any ideas about this cold start white smoke would be great!!-
It sounds like you’re running too rich before the car warms up. I’d say check the thermostat but that shouldn’t cause the smoke. Make sure the correct amount of gasoline is making it into the cylinders.
I’m curious…why did you turbo the car in the first place if you don’t drive it hard?
Thanks for the response. Would the car running too rich at start up cause a smoke like this??
“I’m curious…why did you turbo the car in the first place if you don’t drive it hard?”
I basically turbo’d the car for more all around power. Thats one of the reasons why I used a small tubo. The car gives very nice acceleration even at very low RPM. Also on the higway, where non-turbo I would have had to gun it for a pass now I just give it a bit of gas 2-3 psi (low rpm) & I’m gone. I never intended the turbo for racing just an all around more powerfull engine
Another possibility is that maybe your head gasket is letting some antifreeze into the cylinder(s). If that were the case then as soon as the engine gets warm enough, the gasket expands to block the antifreeze. Does the white smoke have any distinctive smells?
The headgasket is brand new though? The smoke really doesn’t have any strange smell mainly just fuel smell but I’m pretty used to that (no cat & all).
With regards to the T for water cooling the tubo. My turbo’s been running without water cooling for the last 30K miles or so. I confirmed that this would be OK with Turbonetics, basically I was told I did not need water cooling as long as I let the car idle 30sec-1min before shutting off.
The headgasket is installed facing the correct way. I’m pretty sure if you install the headgasket backwards all hell breaks loose (not just a little white smoke)… I mean I think the holes do not line up properly at all and it leaks all over.
Anyway I’m sure it is installed the correct way and again the car is running extremely well
My guess is that you might not have gotten the best seal on your new head gasket. Perhaps you have a very slow leak that fills up your cylinders with coolant when you allow your car to sit for an extended period of time. Check your coolant levels and make sure they aren’t diminishing. If they are, this is almost certainly the case. Hope this helps, best of luck.
I dont think this is a head gasket problem at all. If it was you would notice a bad idle and crappy accelleration due to bad compression. You said it runs good all the time but you have this one smoking problem.
You didnt put the head gasket on upside down. I have done that before and the second you start the engine all of the oil shoots out the back of the motor due to the one oil passage that doesnt get sealed with installed like that. It sucks, but it isnt your problem.
Considering the fact that you just had a valve job done, that would lead me to believe that you might have a valve stem seal problem.
If you put new ones on when you did the valve job then they may have been installed wrong or you got the wrong ones.
If you didnt replace them with the valve job then you might have had some bad ones all along.
There is another possibility though. You said you dont have a cat on. The same thing was happening with my friends b18c powered civic running straight through exhaust. It would have that constant white smoke while idling and that went away when he put a cat on.
I think that is most likely your problem and you may have just noticed because you were doing some inspections or something after the valve job.
Look into it and see what you can find out. Put a cat on there to see what happens and whether that fixes the smoke problem, which I am sure it will. Even a high flow cat would help out a lot and catch all the crap that is escaping through the exhaust.
If you need anymore help or advice just post it up and I will do what I can to help you out and get this taken care of for you.
Thanks guys for all the input. I’ve been away on vacation for a bit so I haven’t really had a chance to work on the car. I am definetly going to check out all your suggestions. And I will keep you posted!
