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Thick white smoke on first start up after sitting overnight.
Posted: Fri Dec 14, 2018 10:43 am
by Highway Patrol
Hello everyone, I’m freaking out at the moment because my 1994 SSEi has a thick cloud of white smoke on startup. I really don’t know how long this has been happening exactly because I’ve been just dismissing it as just being condensation (it’s like 36 degrees F here in Massachusetts) but now I’m coming to the realization that this could be something a whole lot worse. The smoke goes away after running for a minute of two so I’m worried that my LIM gasket is blown. I’ve noticed my coolant level is pretty low but I can only run it in the driveway. Also I checked the oil and I didn’t see any signs of milkshake so I’m really puzzled. Please any help would be greatly appreciated. I’ll see if I can get some images of the smoke up on here but I’m sending this from my phone and can’t figure out how to do it.
Re: H E L P
Posted: Fri Dec 14, 2018 10:44 am
by Highway Patrol
Correction: 26* not 36* F.
Re: Thick white smoke on first up after sitting overnight.
Posted: Fri Dec 14, 2018 1:51 pm
by Highway Patrol
Just uploaded a video of what's been going on onto youtube (I had taken this video originally to complain how it doesn't like starting on the first try with the remote start, but as you can see, it became much more than just that

). Here's the link:
https://www.youtube.com/watch?v=OxSo1JBq7CA
Re: Thick white smoke on first start up after sitting overni
Posted: Fri Dec 14, 2018 10:21 pm
by J Wikoff
Most likely the LIM gaskets are leaking. Head gaskets are a possibility, but not likely. Or maybe the throttle body gasket.
Re: Thick white smoke on first start up after sitting overni
Posted: Fri Dec 14, 2018 11:33 pm
by Highway Patrol
J Wikoff wrote:Most likely the LIM gaskets are leaking. Head gaskets are a possibility, but not likely. Or maybe the throttle body gasket.
Ouch. Well, thanks for helping me narrow things down. I have heard that most 3800s do end up experiencing intake manifold gasket failure at 80-100k miles (I’m sitting at 106,758).
Re: Thick white smoke on first start up after sitting overni
Posted: Sat Dec 15, 2018 12:29 pm
by J Wikoff
It's far more common with the 95+ L36 and 96+ L67, but older 3800s aren't immune to it. It's a few hour job, not bad. It's good that it's not in the oil, but I wouldn't wait to fix it.
Re: Thick white smoke on first start up after sitting overni
Posted: Wed Jan 23, 2019 7:46 pm
by imidazol97
My suggestion would be to change the oil frequently until you can get the LIM gasket and manifold replaced to stop the coolant getting in. I'm not
clear if you're driving it or it's just sitting in driveway and you're starting it, but I'd change the oil out that is contaminated with coolant and put
in whatever is cheapest oil that meets the specs (1094?) for GM from Walmart.
That's what the oil testing folks in Ft. Wayne told me to do when they detected sodium and potassium in the sample I sent to check on mileage
since it was my first full synthetic. They said changing the oil frequently would keep the coolant level low at the seep rate I probably had and would
prevent damage to the bearings hopefully. Cheap insurance if you can't get to the job soon--just change it every 1000 miles.
Then change the oil with cheap stuff after replacement of intake to pick up any residual coolant left in bottom of engine, and drain at 500 or 1000 and replace with what oil you choose to use.
Re: Thick white smoke on first start up after sitting overni
Posted: Thu Jan 24, 2019 1:17 pm
by Highway Patrol
imidazol97 wrote:My suggestion would be to change the oil frequently until you can get the LIM gasket and manifold replaced to stop the coolant getting in. I'm not
clear if you're driving it or it's just sitting in driveway and you're starting it, but I'd change the oil out that is contaminated with coolant and put
in whatever is cheapest oil that meets the specs (1094?) for GM from Walmart.
That's what the oil testing folks in Ft. Wayne told me to do when they detected sodium and potassium in the sample I sent to check on mileage
since it was my first full synthetic. They said changing the oil frequently would keep the coolant level low at the seep rate I probably had and would
prevent damage to the bearings hopefully. Cheap insurance if you can't get to the job soon--just change it every 1000 miles.
Then change the oil with cheap stuff after replacement of intake to pick up any residual coolant left in bottom of engine, and drain at 500 or 1000 and replace with what oil you choose to use.
Hey, thanks for the feedback! The car is not on the road currently due to it not being registered. I used to start it every single day and let it run but, now, I discovered a new issue. Right as the engine first fires over, there is a quick hint of spark knock. Also, whenever the engine is revved very quickly (from idle to immediately giving half throttle) you will get spark knock. I don't think that it's bearing or rod knock because it doesn't happen if you gradually increase the throttle.
Forgot to add, the engine has a vacuum coming from the oil filler cap and the dipstick tube? If I remove either of them while the car is running, the idle will drop dramatically (to the point where the engine would probably die if I didn't put it back in) and I will get a terrible spark knock sound? I've got a video of the issue on my phone that I'll be uploading onto YouTube and then linking it onto here in a few. I've asked multiple people about this issue and I've narrowed it down to either the PCV valve or (as discussed above) the LIM gasket.
Re: Thick white smoke on first start up after sitting overni
Posted: Mon Jan 28, 2019 9:02 pm
by Highway Patrol
Forgot to post the link to the video I threw together a couple days ago:
https://www.youtube.com/watch?v=q08AWhvu7qc
Re: Thick white smoke on first start up after sitting overni
Posted: Mon Jan 28, 2019 11:22 pm
by J Wikoff
You may have a stuck pcv. Super cheap and easy to replace. High vacuum at idle should pull it closed and prevent such a problem like that.
I have a theory that your tb gasket is leaking. It's a high point so it may not leak when the engine is off and get coolant to the oil, but with some pressure while running will put a small stream into the engine.
Re: Thick white smoke on first start up after sitting overni
Posted: Tue Jan 29, 2019 12:42 am
by Highway Patrol
J Wikoff wrote:You may have a stuck pcv. Super cheap and easy to replace. High vacuum at idle should pull it closed and prevent such a problem like that.
I have a theory that your tb gasket is leaking. It's a high point so it may not leak when the engine is off and get coolant to the oil, but with some pressure while running will put a small stream into the engine.
Huh, I never even gave the TB gasket any thought? I'll have to check that. And would a failed PCV valve cause that big of a vacuum? I've had other people telling me that it could the LIM gaskets causing this, which kind of scares me. God I hope it's something simple.
Re: Thick white smoke on first start up after sitting overni
Posted: Tue Jan 29, 2019 1:02 am
by J Wikoff
Tbh, I don't know how much vacuum a stuck pcv will cause. You can check the valve though. Remove the little black plate from the top of the screen. The valve and a spring is right under it. The valve should rattle if you take it out and shake it.
And yeah, a Lim gasket could cause it too. It's not a huge job. It is intimidating, I've been there. But once you get in there, it's not so bad.
Re: Thick white smoke on first start up after sitting overni
Posted: Tue Jan 29, 2019 10:49 am
by nos4blood70
For what it's worth, my LIM gaskets failed at 60k miles.
BAD LIM GASKETS
Posted: Thu Jan 31, 2019 8:50 pm
by MKMike
BAD LIM GASKETS see #s 13 and 19 here
[url]https://www.facebook.com/GM3800Tips/posts/551818071634026?__xts__[0]=68.ARCQiE5GJ7VBAD-NJHVIifDKGktpImfaAY-ZpianunYUIfa5P5HPBmskqo3IWSf_vOIpWt4EVrLj7PcpqVNfGdSG_1elr_1IRgf5r752I6F0FVydPlaPVpuGrPf1yadhuv67rIP3giG-RL2nGSbm7SPKNcEfoUlhSgq4Eb2YVWA4fJ0sR4HmK5Yh-xZunRus9ZB1T9eB-s05HlO-NLg5xJRMODLry4quVwl5UTwfxKV3LatIi3lS8YkKlyH-r2p7Gdv6-1A0KbTMPDRuuCwNgU5nUveAbhARqzJQn4g4JrS7o4osz3R1CidMSteJn-IY3n5gtrKExoZOfnpYK7o&__tn__=K-R[/url]
If link fails to work, either copy and paste it OR go to Facebook, search for user GM 3800 Service Tips, Techniques, and Advice and look for post labeled "Quick Note: Signs you have a bad LIM gasket "
Re: BAD LIM GASKETS
Posted: Mon Feb 04, 2019 9:23 am
by Highway Patrol
MKMike wrote:BAD LIM GASKETS see #s 13 and 19 here
[url]https://www.facebook.com/GM3800Tips/posts/551818071634026?__xts__[0]=68.ARCQiE5GJ7VBAD-NJHVIifDKGktpImfaAY-ZpianunYUIfa5P5HPBmskqo3IWSf_vOIpWt4EVrLj7PcpqVNfGdSG_1elr_1IRgf5r752I6F0FVydPlaPVpuGrPf1yadhuv67rIP3giG-RL2nGSbm7SPKNcEfoUlhSgq4Eb2YVWA4fJ0sR4HmK5Yh-xZunRus9ZB1T9eB-s05HlO-NLg5xJRMODLry4quVwl5UTwfxKV3LatIi3lS8YkKlyH-r2p7Gdv6-1A0KbTMPDRuuCwNgU5nUveAbhARqzJQn4g4JrS7o4osz3R1CidMSteJn-IY3n5gtrKExoZOfnpYK7o&__tn__=K-R[/url]
If link fails to work, either copy and paste it OR go to Facebook, search for user GM 3800 Service Tips, Techniques, and Advice and look for post labeled "Quick Note: Signs you have a bad LIM gasket "
Hi! Sorry for taking so long to get back to you guys. I've been super busy with homework and my job and haven't had the time to reply. Anyways, I actually talked to the 3800 guy (the Facebook page that you linked) on Facebook Messenger and he told me that it was either the LIM Gasket or the PCV Valve. My car is currently covered in a layer of snow, but it's supposed to get up to like 54 degrees today and Tuesday so I'll see what I can do about checking the PCV Valve. I still haven't gotten around to calling my mechanic either (I'm 17 and I'm not sure if I'll be able to do the Lower Intake Manifold Gaskets all by myself) but I'm going to try and work on the car whenever its warm outside. By the way, how bad is it to run the car with this current issue? It's been sitting for two weeks now and I want to run it for a little bit.
Re: Thick white smoke on first start up after sitting overni
Posted: Mon Feb 04, 2019 9:40 am
by Highway Patrol
nos4blood70 wrote:For what it's worth, my LIM gaskets failed at 60k miles.
What symptoms did you have? The same that I'm having or were they different?
Re: Thick white smoke on first start up after sitting overni
Posted: Mon Feb 04, 2019 11:25 pm
by J Wikoff
If there's no coolant in the oil and not overheating, it's ok to run.
Re: Thick white smoke on first start up after sitting overni
Posted: Tue Feb 05, 2019 2:44 pm
by Highway Patrol
J Wikoff wrote:If there's no coolant in the oil and not overheating, it's ok to run.
Good to know haha. If the oil did have coolant in it though, would I see milkshake immediately (lets say I run it for 10 minutes) or does that take hours of normal driving for it to look like that? And if it is getting that spark knock, is that dangerous to the motor? I've heard that it can cause legitimate damage to the piston surface and whatnot.
Re: Thick white smoke on first start up after sitting overni
Posted: Tue Feb 05, 2019 7:12 pm
by J Wikoff
Knock can be bad. How do you that's what it is?
Milkshake would probably show up on the dipstick if it has been run recently, or under the oil fill cap.
Re: Thick white smoke on first start up after sitting overni
Posted: Tue Feb 05, 2019 7:40 pm
by Highway Patrol
J Wikoff wrote:Knock can be bad. How do you that's what it is?
Milkshake would probably show up on the dipstick if it has been run recently, or under the oil fill cap.
I don't exactly know what it is to be honest. In the video I linked, the engine makes that knocking sound when I remove the oil cap. I just ran it for a good hour today (it was 62 degrees outside) and took a lot of video. Even though it was warm outside, I still got some steam out of the exhaust but nowhere near as much when compared to the 26-degree start ups. I'm throwing together another video at the moment and it should be up within a couple hours.