Smoke coming from underneath
Thread Starter
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Joined: Sep 2011
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Smoke coming from underneath
So I drive my CE a lot for work, about 100 miles a day m-f. I have about 30-45 mins of stop and go traffic in the evenings and while in that stop and go traffic I'll notice a lil bit of smoke coming out from underneath on the passenger side accompanied by this burning smell. I also notice a slightly fainter burning smell even without the smoke. It only seems to happen after driving for a bit and/or if it's warm outside. If it's really cold out then I don't see any smoke but I still get that odor. If I lid the hood then the smoke will reroute itself to the engine compartment. Now this smoke is not enough to envelop me or anything but it's still rather concerning. Ideas?
Thread Starter
Advanced
Joined: Sep 2011
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That's the thing is that I rarely might get a drop or 2 on my carport but I just did an oil change (~4000 miles) and when I did it was maybe 3/4 a quart low. I would think that with this happening so regularly that I would have lost more oil than that if it was an oil leak causing it. Or am I wrong there?
Intermediate
Joined: Jul 2014
Posts: 41
Likes: 0
From: Alabama
Not really. We are talking about drips. Put a piece of cardboard up underneath it for a few hours. Running and engine off. It will give you a good idea where it's coming from. Then jack that bad boy up and get busy. 👊
Burning Brakes
Joined: Dec 2014
Posts: 1,038
Likes: 44
From: Pensacola Florida
As you're driving it's probably leaking a bit more than idling, and when moving it's being blown back on the exhaust and that's from where the wonderful blue smoke is coming.
I had an embarrassing amount boiling out at stop lights before I added the Lucas Oil Stopleak.
Rick
I had an embarrassing amount boiling out at stop lights before I added the Lucas Oil Stopleak.
Rick
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Racer
Joined: Dec 2007
Posts: 416
Likes: 3
As a test, when it's nice and hot turn it off and pull the dipstick out and let it drip on the exhaust manifold, it'll let you see how much smoke comes off one drip. Trans fluid puts out more smoke.
Le Mans Master
Joined: May 2006
Posts: 7,708
Likes: 266
From: indy indiana
The thing is.. an oil leak is more dangerous than a fuel leak, in this way. Fuel will hit a hot spot and evaporate quickly b4 catching fire. oil will dance and sizzle, getting hotter and hotter till IT CAN get hot enough to ignite. Of course we all know that fuel doesn't ignite..its the fumes that are dangerous, and that,is of course, more dangerous than oil but were talking about leaks/spills without an igniter.
Safety Car
Joined: Aug 2009
Posts: 3,751
Likes: 276
From: Melbourne, Victoria, Australia
Do not forget the transmission, the rear seal is above the cat.
One drop on the exhaust makes quite a bit of smoke.
Burning Brakes
Joined: Apr 2011
Posts: 917
Likes: 25
From: College Station Tx
So, in trying to chase down a leak on my '95, I've replaced, oil pan gasket, valve cover gaskets, opti and water pump seals. There were small leaks from each of these places, and I still have a small leak. I have it narrowed down to rear main or intake. Going to do the intake first and hope that it isn't the main.
It is difficult to locate the source of small, slow drips. Also, it will take a while for the drip to cause a noticeable change in oil level. And, as said already, one small drop can cause a lot of smoke.
Lastly, after an oil change, I noticed a lot of smoke. Turned out that I didn't tighten the oil filter adequately.
It is difficult to locate the source of small, slow drips. Also, it will take a while for the drip to cause a noticeable change in oil level. And, as said already, one small drop can cause a lot of smoke.
Lastly, after an oil change, I noticed a lot of smoke. Turned out that I didn't tighten the oil filter adequately.
Melting Slicks
Joined: Jan 2001
Posts: 2,996
Likes: 304
From: MOORESVILLE NC
My 88 700R4 leaked onto the passenger side exhaust sometimes. It was a pump. Had to pull the 700R4 out for a rebuild. No more smoke.
I hope it is only a valve cover leak. Put a piece of cardboard under the area so you can see what color the leak is.
I hope it is only a valve cover leak. Put a piece of cardboard under the area so you can see what color the leak is.
Pro
Joined: Oct 2012
Posts: 580
Likes: 121
From: Grapevine TX
It's a term used for the front and rear ends of the intake manifold. I think it's because the top edges of the block look kind of like the great wall of China in the way they curve.
Another possibility for smoke and smell is if you ran over some plastic and it stuck to the exhaust. It can take quite a long time for it to burn completely off. I agree with the others though, it sounds more like an oil leak if it's been going on for more than maybe a couple weeks.
Another possibility for smoke and smell is if you ran over some plastic and it stuck to the exhaust. It can take quite a long time for it to burn completely off. I agree with the others though, it sounds more like an oil leak if it's been going on for more than maybe a couple weeks.
Melting Slicks
Joined: Nov 2005
Posts: 3,323
Likes: 142
From: Green Valley Arizona
So I drive my CE a lot for work, about 100 miles a day m-f. I have about 30-45 mins of stop and go traffic in the evenings and while in that stop and go traffic I'll notice a lil bit of smoke coming out from underneath on the passenger side accompanied by this burning smell. I also notice a slightly fainter burning smell even without the smoke. It only seems to happen after driving for a bit and/or if it's warm outside. If it's really cold out then I don't see any smoke but I still get that odor. If I lid the hood then the smoke will reroute itself to the engine compartment. Now this smoke is not enough to envelop me or anything but it's still rather concerning. Ideas?
oil filter adapter bolts
oil filter
front cover seals...all three of them
front or rear edge of block where intake sits
oil pressure sender at back of block
oil pan drain plug
rear main seal
Get under car and wipe off any oil.
Idle engine for a good 20-30 minutes and if you can be careful and be SAFE, get under the engine and looks for drips. Going to be a bit warm under there though and very hot exhaust piping.
Should be able to get the leak determined.
Good luck.
Safety Car
Joined: Aug 2013
Posts: 4,429
Likes: 605
From: Minneapolis Mn
I didn't notice what the aroma is so here's one I've seen before. It's possible if the pipes are too close to have the exhaust cooking the body in one spot or other.
Not the first thought but it's possible and seems like all the leak points have been listed.
Good luck
Not the first thought but it's possible and seems like all the leak points have been listed.
Good luck
Thread Starter
Advanced
Joined: Sep 2011
Posts: 95
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So I'm just going to do a full top end kit for the gaskets. I was going to just do it piece by piece but figured why not? Now the question is I seem to have issues finding part numbers for an lt4 gasket set. Also I've heard talk of an off road intake manifold gasket, what is the part number for this and is it worth it? Also any info on this subject as far as what's better for what and tips would be appreciated. And lastly any thoughts on a lower temp thermostat?