White smoke out exhaust when RPM's get up (4500)

[1990QOwner]

I have a 1990 Q45. I have noticed that whenever I throttle it and it hits the power band (4500 RPM's) than a cloud of white smoke comes out the exhaust . It is enough smoke that I can see it from the mirrors while going over 45. Can anyone tell me what this means or what I can do to fix this? Thanks.

[qship96]

Be very careful,as previous owner may have stuffed muffler with bags of cocaine to smuggle across the country and forgot to remove before selling the car-they are now rupturing,resulting in the clouds of white smoke you are seeing!

[1990QOwner]

O OK, mabe that is why whenever I do it than the people behind me crash. LOL, you speaking from experience?

[goody90q45]

White smoke = Unburnt fuel. Did I read in one of your other posts that your mileage was in the 10mpg range? I think you have big problems with fuel injectors. Start by ohming them, it's quick and free. I suspect you have a few dead ones. If this isn't the problem it didn't cost you anything to rule it out.

http://www.q45.org/ohminjectors.html

[1990QOwner]

White smoke = Unburnt fuel.

http://www.q45.org/ohminjectors.html

Makes sense. Sorry about being mechanically illiterate but what do you mean by "ohming them"?

[1990QOwner]

O, I didn't see the link. I will check it out.

[qship96]

I still think it is powder cocaine,but if not,it is just water vapor and normal for the q45.

[1990QOwner]

It isn't normal for warmed up Q's is it?

[Q45tech]

Burning gasoline generates CO2 + H2O vapor

[1990QOwner]

Mabe I should get a picture. This is a large cloud of white smoke. I dont know any other way to explain it. I also have been getting horrible fuel mileage. Do you think it could be bad injectors? I have a new TCU coming and a FSM. I will be doing some work on it.

[Skibane]

Although burning oil has more of bluish tint to it, probably still wouldn't hurt to make sure that the oil level is right on the mark. If it's overfilled, you're likely to see some smoke at high RPMs.

[1990QOwner]

I had it serviced just over a week ago and they did put synthetic oil in it. Does the synthetic oil make any difference?

[Skibane]

Nope - All that matters is the amount...

[Q451990]

I always thought white smoke = oil or water vapor (coolant), and black smoke = fuel?

Heath

[qship96]

blue smoke-oil burningblack smoke-running very rich,fuel/air ratio issuewhite smoke-water condensation or blown headgasket burning coolant{sweet smell}

[maxnix]

If you suspect the engine has ever been overheated, keep a close eye on your coolant level.

If the vapor smells sweet, it's not blow but ethylene glycol. Not a good sign.

[1990QOwner]

That isnt too encouraging because the radiator has a leak. I have been keeping the coolant level up but a while back I noticed the engine temp was way up, it wasnt clear to the overheat point yet. So I shut the engine off. Do you think it could have done damage?

[ScottJackson]

YES. Put some of the stuff in the coolant that reacts to combusted gasses being present in the coolant. If it says you got compression getting into the radiator, you got problems. From there, pull all the spark plugs. One will likely be substantially cleaner than the others. That'd be the cylinder that's getting coolant in it. Aluminum expands twice as much as iron when heated. Overheating any aluminum engine or engine with aluminum heads usually ushers in the end of that engine... very quickly. I don't know why manufacturers don't put some ignition disabler that shuts the car down when the block/heads get above a certain temperature, especially in the aluminum engines (which is almost all nowadays). I know it could be dangerous in an emergency situation, but make a dummy light come on at say 250* saying the engine will shut down from heat soon, then at 260* have it cut power to only 4 cylinders and have the dummy light start flashing with maybe a beeper too. Then, 15 seconds later have it shut down until it's reset below a certain temperature.

[1990QOwner]

I have parked my Q and haven't driven it since my last post. I noticed that the coolant reservoir was clear full and the engine was still getting quite hot. So I took off the radiator cap off and the radiator was empty. What does that mean??

[maxnix]

You may have air in the coolant system and thus maybe hot spots where the coolant is missing. You have to understand the coolant heat gauge is heavily damped and not indicative of a specific temperature at any particular time.

You are wise to park it until you do a compression test and report back. If you have a bown head gasket or warped heads from the overheat, then a repair or repalcement strategy will have to be implemented to correct it.

[1990QOwner]

How do I go about a compression test? Is it something I can do or do I have to go back to the shop that doesnt know anything about foreign cars?

[qship96]

I have parked my Q and haven't driven it since my last post. I noticed that the coolant reservoir was clear full and the engine was still getting quite hot. So I took off the radiator cap off and the radiator was empty. What does that mean??

Only 2 possibilities-it is leaking externally{check under plenum and under car| or internally and being burned thru the exhaust-not good at all

[1990QOwner]

I suspect that it is doing both. The radiator has a hole in it and does leak (as I have said in a previous post). Also I suspect that it is leaking into the exhaust. I have just talked to a mechanic and he told me that the only way that overheating could damage a head gasket is if it had overheated for a long time which I don't think it did. I think I will check into the injectors before assuming the worse with the head gasket.

[qship96]

dont waste your time with injectors until you figure out coolant issue,as if headgasket has blown,you will have quite a problem on your hands...must then decide to junk the car or put a rehabbed motor in it,and if the body and rest of car are not in excellent condition this makes little sense.

[1990QOwner]

The interior and body are in excellent condition. Check out this thread: zerothread/287180. I have already considered selling it for parts or selling it. If the head gasket is not blown than I will probably just keep it and get the other car that is on ebay and swap out parts.

It does sound fun to just swap parts out and twink on it in my spare time. How can I tell for sure if the head gasket is blown?

[maxnix]

. How can I tell for sure if the head gasket is blown?

Start with a compression test.

[ScottJackson]

empty radiator but full overflow reservoir can also often mean a cracked/broken hose connecting the two. It will allow excess coolant to go into the overflow res. but won't hold a vacuum when the engine cools to pull the coolant back into the main cooling system. There's a LOT of engines that get damaged from lack of coolant simply because the owner checks the reservoir only and never under the actual cap.