Okay, I need some insight. My car likes to smoke every once in a while and I can't figure it out. It'll smoke after I run over some really bumpy road then will smoke a bit then be fine. Now could this have anything to do with my bad brake master cylinder/brake booster (every so often my revs'll pulsate in time with my brake pedal) Odd right? The smokes off white or grey and smells sorta sweet. Any ideas? Thanks everyone.

 

sounds like antifreeze, if antifreezeis leaking onto anything hot that would do it

 

antifreeze may be overflowing, hence why it smokes on a bumpy road. what is the temp like?

 

is the smoke coming from the enigne bay or the tail pipes

 

antifreeze on the exhaust..you should check hose clamps and hose connection points .wipe every thing that has a hose on it off ..take it down the bumpy road and look for the wet spot(hehheh)...or pressure test cooling system,,sounds like it may be near the back of the engine.. firewall pass side ..check the heatercore connections on the outside too..good luck

 

If we are talking about smoke through the exhaust then:

White smoke= water seeping into the combustion chamber. Usually a bad seal.
The sweet smell is the coolant/antifreeze.

Black smoke= Oil being burned. If it is just at start up it is normaly from a little
residue from the oil meetering pump in the chamber. If it continues
for a long period of time or while you are running, usually it is a
bad oil seal.

Blueish smoke= Usually gas being burned. Usually in the mornings, the injectors
could be staying open and dripping overnight causing this.


If it it other than through the exhaust then you should check your heater, block hoses, bac or any hose that carries water. You might have a drip/leak that is falling on a hot surface when you are on a bumpy road.. As said before the "sweet smell" is indication of coolant. This shouldn't have anything to do with the brakes.

 

any spotting on the ground?green?drive it onto a big piece of cardboard..you'll get a fair idea where the leak is,if it is leaking externally and you will know by the color of the fluid What it is...go by the judge by using the tire marks as a reference.park the car beside it and hunt it down..

 

Hmm, wow you guys are awesome. Lets see. The smoke's coming from the tail pipes first off and the temp's fine, never gets past halfway and thats really rare.

I haven't noticed any spots on the ground but I'll do the cardboard trick soon.

Is it possible for brake fluid to get into my engine and burn off??

 

Well, if the smoke is actually coming out of the tail pipes (and not smoking from something near a tailpipe), you won't necessarily see any leakage. The leakage would be internal to the engine if the smoke is coming out of the tailpipes. Is your coolant level dropping? That would certainly be an indication of such a problem, especially if you have no obvious coolant leaks.

No way for brake fluid to get into the engine unless you intentionally pour it in. Is the fluid in your brake master cylinder dropping? If so, that's either a separate problem or possibly the fluid is somehow spraying onto a tailpipe and giving the appearance of the smoke coming FROM the tail pipe.

 

Hmmm.. yeah I have to refill the ****** every couple of days. That'll be fixed soon though. I'll keep a closer eye on the coolant levels.

 

Um... you mean you have to refill the coolant every couple of days?

 

Nope sorry, I have to refill the brake fluide every couple days. (I like that one much better)

 

Ah, yes, that's better.. . but it sounds to me like you have a pinhole leak in your brake lines, somewhere... possibly in the rear where it passes over the exhaust? I'd put the car up on jack stands, get underneath it and watch what happens when someone hits the brakes.. Brake fluid can smell sweetish, if burnt... Trust me on this one

 

Ahh, hmm, first thats been suggested. I'll give it a shot. I''ll tell the my mechanic to chek when he's replacing the front diff. mount. Thanks.

 

I think the driver may be the only thing thats "sweet"....................

 

...Are you hitting on me? LOL

 

Sounds like a bad master cylinder to me. Sounds like your brake fluid is running out of your master cylinder and into the brake booster. Then, the vaccum from the engine is sucking the brake fluid from the brake booster to the engine and burning it. That would cause the sweet smell, and the disappearing brake fluid.

 

Okay that was how it was explained to me before but thought that they were wrong. Can that damage my apex seals at all?

 

brake fluid likes to eat paint, but I dont think it would hurt your apex seals.

 

Brake master cylinder and brake booster are NOT connected by anything except a small metal pushrod. That means there is no way you are getting brake fluid into the brake booster from the brake master cylinder unless you have some HUGE holes in your system and that would mean your brakes would not work at all. Think about it... if mazda made it so brake fluid was running into the booster at all then their would be a chance when they get all old that the system would fail and brake fluid would be shot into the LIM or UIM (can't remember where the vacuum hose comes from). This would equal stupid designing and all rotories would probably be dead due to this.

If you don't believe me check out this website on how power brakes work.

http://auto.howstuffworks.com/power-brake.htm

 

I know how power brakes work. What im saying is if the seals in the master cylinder go bad it CAN push brake fluid out the back of the master cylinder and into the booster. It happened on a honda civic a friend of mine had.

 

I KNOW my brake master is bad and my brake booster looks horrid. So, I'm going with this guy.

 

OK, let's say that your master cylinder went bad and you were leaking fluid out the back of the cylinder and onto the booster. It would have to get past the push rod and the push rods seal to even get into the booster. Very highly unlikely but lets say it happens. After that seal breaks then boom, you just lost your vacuum seal making it extremely hard to press your brakes and that's why I said...


Seeing as this has only happened to one person ever I didn't think it was viable. If your brakes aren't working why would you continue to use the car and possibly get brake fluid into the vacuum.

 

Are your brakes still easy to press? Then that means you still have vacuum, meaning no leak into the booster. Please try again.

 

Also this would mean you would have a large vacuum leak causing your car to possibly not run at all or just run like crap.

Seriously guys try to think about what would PROBABLY happen not what could POSSIBLY happen. You might as well say that a monkey ate all the leaking fluids during the night so you don't see any on the cardboard.