SOLVED: White smoke puffing out of exhaust after brake job

So today I resolved leaking brake fluid by replacing my master cylinder, and was ready to be happily on my way when I cut the engine on and noticed a ton of smoke pouring out of my exhaust.. truly anticlimactic.



I immediately started to wonder if my head gasket was blown? Maybe I spilled some brake oil into the exhaust? Maybe something to do with these hoses I disconnected and then reconnected?? Take a peak..



On a positive note the engine sounded normal and my coolant reservoir was unchanged while there was no overheating at all. Also the smoke was white not blue, and there was also water dripping out as well which meant maybe it is a water leak? Also a slight sweet scent to the smoke. A couple buddies in the area took a look and were also stumped. We left the car running and the heavy smoke did slow down a tad, especially while accelerating, but as soon as I take my foot off the accelerator the smoke gets slightly heavier again.

After a couple hours it’s not as heavy but there’s still white smoking dissipating, especially on idle.



On a side I recently had the timing belt/water pump replaced if that means anything. For the time being I’m going to let her sit for a couple days as she’s my second vehicle, and also don’t want to push it if it indeed is a head gasket about to go. Regardless I love these 4.7s!!

Any input would help friends!

 

Check your oil dipstick and see if it has a somewhat white or frothy look to it.

 

I also forgot to mention that! Oil is a very healthy golden brown, no milky/cloudy color to it.

 

How are your brakes?

How's your brake fluid level? Is it possible brake fluid is leaking past your new master cylinder, getting into the vacuum booster, then being drawn into the intake manifold?

 

Checked brake fluid level this morning, not a difference. Buddy of mine said good chance it’s valve seals?

 

Not sure if this is even the right direction to point you but you can easily remove the intake tube to the throttle body and see what it looks like.

 

The fact that you mentioned slight sweet scent tells me its coolant you're burning. When my T100 lost a head gasket it was like burning candy and white smoke. It doesnt take much to totally whiten the exhaust smoke, you may not notice the reservoir lowering for a while. It is odd that it happened right after the brake repair though...

 

That ^

Or


Not familiar with Tundra braking systems but if it was most any other manufaturer, I'd say you have brake fluid going to your intake through the vacuum hose.

 

I just installed an new engine on an Escalade original broke a rod I reused original intake and injectors wen I started up the new engine it was running rough and billowing out white smoke started diagnosing the problem and found a stuck open #6 injector replaced it smoke is gone now new engines runs perfect

 

I dont think its brake fluid. I swapped my booster and MC recently, I dont see any way to get enough fluid in the hose for that much smoke.

I think it is a separate problem that just presented itself.

 

In that case you're burning coolant, sorry dude.

 

Sure sounds like symptoms of a leaking head gasket. Possibly just a small leak of coolant to exhaust so you're not seeing coolant in the oil? How's your coolant level?

 

I'd suggest to annotate your coolant level, drive a bit and check. I heard that driving it while leaking could impact your O2 sensor or CAT though. Should check on that before adding more damage.

 

Unlikely. That would generally cause a "puff" of blue smoke immediately on start-up, and would be done withing a few seconds.

White smoke like that would point more to a substance other than oil. Coolant is likely, but since you just did brake work, brake fluid is suspect.

 

I saw a video of someone who had a similar scenario with a Subaru of theirs. Replaced leaking MC, then once done drove off and a ton of white smoke emitting from the exhaust. If it indeed was vacuumed in, is it just a matter of driving around till it’s all cleared?

My coolant level remains the same after a day. I drove the car around the neighborhood a bit and let it idle for a bit also. No noticeable difference in coolant.

That’s exactly what I am thinking here. One thing to note is today after work I came home and started her up, buddy said a good bit of liquid came out of the exhaust. I want to say it was a clear yellowish color with slight froth? I’m leaning towards brake fluid, but did that much really seep in for a smoke-like vapor to still be emitting? Mind you my MC was probably leaking for a good month if not longer. Im much less likely thinking it was engine oil the level has stayed the same, just as my coolant level. I’m getting those white puffs of smoke on acceleration driving around the block. I’m stumped here folks..

 

smell thesmoke, does it smell like burned oil or like no smell at all. It look like water getting in you engine somewhere, looks like some of the hose are worn out and need replaced, hoses
need to be tight and no leaking.

 

You need a schematic of the plumbing for the system and make sure you have it plumbed right first. Remember, keep it simple

 

You said it smelled slightly sweet right? take a straw and do a little dip into your reservoir and take out a few mL. drop this coolant onto a hot piece of steel or fying pan or something that will vapourise it. is it that smell?

 

This is a good idea , then you’ll know .

 

I had white smoke come out another car. It turned out to be the air oil separator.
They say coolent burning produces blueish and sweet smelling smoke. I had cooler leak in another car in college. I remember it looked white to me and I only noticed the sweetness when a mechanic pointed it out to me.
Good luck.

 

perhaps one of the coolant lines, heater core or throttle body for example could have gotten mixed up for a vaccuum line? until the truck comes up to full temp and the thermostat opens you wouldn't have a mass circulation of coolant to drop the level significantly. It also wouldn't mix with the oil this way. Just a thought. Agree with the above plumbing diagram and recheck.

 

You can also pull your park plugs, if its getting into a cylinder the plug will be very clean looking, it would basically have a steam cleaning.

 

Have you pulled of vacuum lines/hoses to see if any are wet? I am still betting it's brake fluid leaking and burning through the intake.

 

I've had this issue after working on the brakes of a friends Chevy. Best I could figure we over extended the master cylinder when pumping the brakes bake. Brake fluid got into the vacuum system and into the intank. Should burn off as long as it's not still getting past the master cylinder. To keep this from happening again ive started putting a cut 2x4 behind the brake pedal when I'm pumping up the brakes on older vehicles

 

Thanks for all the responses folks. Soo update today, didn’t get a ton accomplished but I’m starting to think could be a break booster issue. When the car is on and idle, none to barely any smoke comes from the exhaust. When accelerating is when it happens, making me assume vacuuming. But amount of smoke is less than previous two days. Also another key tidbit, whenever I pump the brakes with engine on I can hear a hissing noise coming from the pedal area. Now mind you I recently replaced my MC due to leaking, but could it be the booster was bad as well? Or could have all the leaked brake fluid done damage to the booster? Starting to feel my issue is this area ala brake fluid causing the smoke.

Great idea; actually did this and nope it’s not a sweet scent more like oily chemical scent..

Yes I pulled the hose from the booster, no liquid. Both before turning engine on, and after. Maybe a couple days ago it was wet, now the remaining smoke is coming from what’s seeped into the engine? Puzzled a tad with this.

 

As a follow up to my above experiment, the next step would be to similarly drip some of your brake fluid onto a frying pan or hot steel and smell that. if you can eliminate one or the other as your source of the problem it would obviously be helpful. Also, if you burn your brake fluid and its the smell coming out the tail pipe you should be very happy and maybe go buy a lotto ticket!

 

Cool hack to vaporize the liquid and smell it. Any concern over toxicity?

 

Sunscreen is toxic, if you eat enough of it.

 

True... water as well.

 

I’m replacing the brake booster later today, hoping once I do I notice the old one is still wet from all the original leakage & my problems are then solved.. its’s far too coincidental this occurs right after replacing a leaking MC.. If so i’ll hold off on lotto hopes till society returns to normalcy