'91 Grand Marquis, stock SEFI 302, AOD tranny, and dual exhaust. Any thoughts on what would cause a plume of white cloud/steam to emit from the car when I downshift out of overdrive into 3rd or 2nd when I get on it to get up a hill or merge onto the interstate? Under normal/light throttle driving this does not occur even if I downshift out of overdrive into 3rd and not get on it, no white cloud is apparent. It's not an oil burning cloud as it is bright white and dissipates like it's steam or some type of vapor coming from the engine or tranny. My friend was behind me when this happened and he said it smelled like burning rubber. Another friend said it smelled like gas. Could it be the bands inside the tranny slipping during high revs in 2nd or 3rd causing this white cloud that dissipates? Anyone else experience this weird occurrence?
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Well, if the trans was leaking you'd see puddles when parked and the dipstick would be low, only way it would smoke.
Light oil burning is often white, so is coolant. Is your coolant level high or low or contaminated? When coasting there is a lot of vacuum inside your engine, as it is trying to pull air in the cylinders from anywhere possible. If your valve seals are bad & your guides sloppy, it will pull air and oil in from them and youll see that burn when fuel is reintroduced to the combustion chamber when you get back on it.1985 LTD Crown Victoria - SOLD
1988 Town Car Signature - Current Party Barge
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I'm not sure that it would be caused by the trans slipping, whether it is or isn't slipping.
Can you reproduce the cloud if you stomp on the throttle while the car is parked?
Does it seem to be more on one side or the other of the car?
My thought is perhaps a pinhole leak in a coolant hose.
If it's mainly on the passenger side, it could be one of the heater hoses. If it's on the driver side it could possibly be the EGR cooler lines (those are fun to get at without removing the upper intake.)
I once had a pinhole leak in one of the small hoses at the water pump. I couldn't pinpoint it until I opened the hood and pulled the throttle open by hand. Each time I would rev it the coolant would shoot up, the cooling fan would then blow it back all over the open hood. For whatever reason I guess it was a small enough pinhole that I couldn't see the leak unless I got on the throttle.
This may not be your issue, but it should give you something to rule out. Check all the coolant hoses.Last edited by VicCrownVic; 08-01-2018, 08:46 AM.Vic
~ 1989 MGM LS Colony Park - Large Marge
~ 1998 MGM LS - new DD
~ 1991 MGM LS "The Scab"
~ 1991 MGM GS "The Ice Car"
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There is the possibility that you're looking at residual moisture in the exhaust being suddenly evaporated and pushed out by the sudden increase in temperature associated with a sudden rise in engine RPM and load. However, this would hardly be noticeable.
There is also the possibility that your intake gaskets are bad causing any of #1, 4, 5 or 8 to pull coolant from their adjacent coolant passages and burn it. It doesn't need to be a lot of coolant to be visible, but you'd probably be adding some every 3-6 months.
There is only one band in an AOD, for OD, so it's out of the picture for 3 and below. However as with any time a question about the AOD comes up, make sure the TV cable is reliably attached with a correct grommet/bushing.
Thinking outside (or under) the box, it might be something happening inside your cats...cat material burning? Broken apart cat dust being blown out forcefully by the sudden increase in exhaust flow? I'm reaching here, but it's not so unlikely with a car this age.
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Can you reproduce the cloud if you stomp on the throttle while the car is parked?
Does it seem to be more on one side or the other of the car?
cat material burning?
Could be possible I guess, I don't know. They are the original cats on it. When this happens there are no strange noises, pinging, or anything. The check engine light doesn't even come on.
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+1 eating coolant.
Go for a normal drive and then let it sit overnight. Should pull a slight vacuum when you open the radiator cap. If not, it’s very likely leaking somewhere.1990 Country Squire - weekend cruiser, next project
1988 Crown Vic LTD Wagon - waiting in the wings
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My firebird poofed oil exactly like you described, whiteish mostly, sometimes with a tinge of blue. Bad valve seals. Would not burn while cruising. Reving it up in neutral and then letting RPM fall to idle and revving up again should produce smoke if it oil was getting past the guides/seals or rings. Might also puff if coolant is getting past the headgasket or somewhere else. Worth a shot and won't hurt anything.
But I suspect you are eating coolant from somewhere. Keep an eye on the level, keep an eye on the oil dipstick too. When I redid the EGR/Throttlebody gasket on my '88 I noticed a nice clean streak where coolant was leaking into the intake. Never saw it out the exhaust. I only fixed the issue when I saw it leaking onto the valve cover. Not surprised it isn't setting the CEL.Last edited by DerekTheGreat; 08-01-2018, 12:26 PM.1985 LTD Crown Victoria - SOLD
1988 Town Car Signature - Current Party Barge
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That TB gasket could also be suspect if it’s seeping through and leaking into that.
My Cars:
-1964 Comet 202 (116K Miles) - Long Term Project
-1986 Dodge D-150 Royale SE (112K Miles) - Slowly Getting Put Back Together
-1987 Grand Marquis Colony Park LS (325K Miles) - April 2017 + September 2019 POTM Winner
-1997 Grand Marquis LS (240K Miles) - The Daily Workhorse & March 2015 + January 2019 POTM Winner
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Chock front wheels, have your foot on the brake (hard) and put it into gear and give it some gas. Have someone inspect whats going on behind the car, under the hood (from the side of the car).~David~
My 1987 Crown Victoria Coupe: The Brown Blob
My 2004 Mercedes Benz E320:The Benz
Originally posted by ootdega
My life is a long series of "nevermind" and "I guess not."
Originally posted by DerekTheGreat
But, that's just coming from me, this site's biggest pessimist. Best of luck
Originally posted by gadget73
my car starts and it has AC. Yours doesn't start and it has no AC. Seems obvious to me.
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When I redid the EGR/Throttlebody gasket on my '88 I noticed a nice clean streak where coolant was leaking into the intake.That TB gasket could also be suspect if it’s seeping through and leaking into that.
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Did it solve your problem?~David~
My 1987 Crown Victoria Coupe: The Brown Blob
My 2004 Mercedes Benz E320:The Benz
Originally posted by ootdega
My life is a long series of "nevermind" and "I guess not."
Originally posted by DerekTheGreat
But, that's just coming from me, this site's biggest pessimist. Best of luck
Originally posted by gadget73
my car starts and it has AC. Yours doesn't start and it has no AC. Seems obvious to me.
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I should clarify that the coolant was getting into the EGR spacer not the throttle body, and the clean streaking was on the inside bottom of the EGR spacer not the throttle body as mentioned in my post yesterday.
Did it solve your problem?
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