White smoke is from antifreeze entering the cylinder and being burned during the power stroke. Since it's only one cylinder, looks like you might have a bad head gasket.

You'll probably notice that your antifreeze is going down and might also notice the plastic antifreeze housing getting dirty from combustion gas being forced into the engine water-jacket contaminating the antifreeze. If not, then you're probably a good candidate to try a head gasket sealer.

You might want to look at using one of the many head gasket sealing products out there that go into your antifreeze.

Bar's has been around a while, with a good reputation. The only one that I've seen tried and did work while they were able to save money and have the head gaskets replaced and heads serviced. Follow the directions closely.

As with any product, this type of product can cause issues down the road. If you have a cooling system that is older and has a lot of internal corrosion, this type of product can cause restrictions in the cooling system. When looking down into the radiator itself, if it looks clean with not visible corrosion, it shouldn't cause any issues.

Good luck.

Have a good day.

 

Yes, apparently you are right, it is leaking from the head gaskets. This remedy that you recommend may help, but mechanics say that it is dangerous and can also damage the radiator. Does anyone have real experience using this product? Perhaps there are specialists who can do this correctly?

 

The antifreeze reservoir is clean, and the oil color is normal (if there was antifreeze, the oil color would be like milk), also the radiator is like new, mileage 76,000

 

So, you have a micro hole in the head gasket which is letting antifreeze weep into the cylinder as the engine cools down. It hasn't gotten large enough to let compression gasses back into the water jacket on the power stroke, hence your coolant is staying clean.

I would try the Bar's and start saving for head job, about $2K, depending on where you get it done. That Bar's might do the trick and last longer than you might think. Just be prepared for when and if it eventually becomes a larger issue in the future.

Good luck.

Have a good day.

 

Oil in the cylinder itself seen after you remove the sparkplug, or in the sparkplug tube after you remove the coil?

Have someone start the car in the morning. Smell the exhaust. If it's antifreeze burning, the exhaust will have a sweet smell to it.

Does it blow white smoke every time you start it, or only when cold/first start of the day?

Have a good day.

 

I changed the spark plug and it started running fine. but when I drive, thick smoke appears periodically. and it doesn't smell like a sweet smell. I can't figure out if it's antifreeze. the oil is leaking

 

Check the PCV valve and if unsure of age, replace. Just want to make sure that the engine is breathing properly. A plugged/malfunctioning PCV can cause oil leaks and excessive oil being burned.

A dirty engine, gunk under the valve covers, can cause upper end oil flooding from being unable to drain back down into the oil pan. When that happens, the excessive oil is too much for the valve seals to handle, getting into the cylinder causing smoke in the exhaust.

You could also have a worn valve guide or valve stem seal on cylinder 4. Both will allow excess oil into a cylinder during the intake stroke.

Oil is leaking from where?

What does the smoke smell like first thing in the morning?

Have a good day.

 

There are no oil leaks anywhere at all. In the morning the smoke smells like gasoline. and the smoke is white and thick. started it cold this afternoon and there was no smoke at all.
But when I started driving after , was white smoke began so many

 

the oil is leaking

There are no oil leaks anywhere at all.

You're sending us mixed messages.

In the morning the smoke smells like gasoline. and the smoke is white and thick.

Thick white smoke that smells like gasoline probably means a large amount of raw fuel is being dumped into the exhaust stream. Perhaps the #4 fuel injector is leaking badly or stuck open? Is it a constant misfire or random?

 

You're sending us mixed messages.

Oil in cylinder
But no oil leaks

Thick white smoke that smells like gasoline probably means a large amount of raw fuel is being dumped into the exhaust stream. Perhaps the #4 fuel injector is leaking badly or stuck open? Is it a constant misfire or random?

 

There is oil in the cylinder, but the cylinder piston is not damaged

That statement was from your original post. Presumably, you inserted a bore scope through the spark plug hole to determine this? If you have a bore scope then you can test the leaky fuel injector theory easily since cylinder #4 is on the front bank. Remove the ignition coil and spark plug for cylinder #4, rotate the crankshaft until the intake valves open, and then do a few ignition on fuel primes without starting the engine to build up pressure in the fuel rail. If fuel starts dripping/pouring through the open intake valves then that would prove the fuel injector is leaking.

 

Rofl....304,000 miles on my 2003 and no fuel injectors ever replaced, though I did have a sticking injecter a couple of times that adding Marvel Mystery Oil to the fuel tank solved with maybe 10 miles of driving.

My 2003 probably has a cracked head or pinhole head gasket leak, and probably a few faulty fuel injectors. I really should try to see what's wrong with it before too much inactivity renders it a rust bucket.

 

I try to remember to run a bottle of Techron through each car once a year in hopes of keeping the injectors clean.

 

It might be worth noting that with that 2003 I had only used 95 octane from 2003 to just about the end of 2015. After that, around the 140,000 mile mark, I started using 87 octane, and only months later I had a sticking injector. From that point, since gas prices were so high, I alternated between 87 and 91 octane, but sometimes would do three fill-ups with 87, then one with 91. That was around the time my CATs started becoming clogged and I began adding lacquer thinner to the fuel, which helped flush/burn out the crap.

 

I normally agree with @PaulDay , but I'm lukewarm on the stop leak approach. It may stop a head gasket leak (or stop it only temporarily) but it's also distributed throughout the cooling system. It's going to add some restrictions in small passages throughout the engine and especially in the radiator. And there is no guarantee that it will actually stop the leak in question.

It's a judgment call. I know of no specialists in using this stuff, and if I were a mechanic I would not use it on a customer's car because of the potential for either no result or a bad result. I tried it on one of my own cars many years ago and it didn't do much.

IMO there is no substitute for doing it right. If your financial situation is such that you have cannot afford to have the job done right, then it's up to you whether you want to try it. It might work, and it might not. If it doesn't and you're forced to have the head gasket changed, I would also flush the bejeezuz out of the cooling system in an effort to get rid of as much of it as possible. If it does work, start saving up for the head gasket job, because it's probably coming soon.

 

what is the possible cost of repairing the head gasket?

 

Call your favorite mechanic and ask. It will be north of $1000.

 

Тhey dont want fix they want to change the engine

 

Тhey dont want fix they want to change the engine

You're the owner, but it sounds like you're not very familiar with mechanical issues. You are in charge of this process, and their recommendation makes no sense, based on the information you have presented.

Unless they can provide a good justification THAT YOU CLEARLY UNDERSTAND for replacing the engine AND YOU AGREE with that explanation, don't do it. I suggest you find another independent mechanic, present them the information that you have, and see what they recommend.

My guess is that they simply don't want to do the head gasket. It's a pain in the butt in the Murano and they may not even feel competent to do the work. There are lots of good mechanics around. Doing the head gasket will be less than half (probably closer to one-third) the cost of replacing the engine, and that's if you find a used engine which has its own past that is unknown to you.

 

I performed an endoscopy and saw a subdect in one cylinder from the head. also the smell of smoke in the morning is sweet

 

What is a "subdect?"

Writing your posts more carefully will help us understand you.

 

leak in the cylinder

 

Seems foolish to replace an engine with 76000 miles on it with a used one with probably similar or higher mileage with many unknowns as to its history. If anything, bite the bullet and spring for a brand new engine.

Replacing the head gasket on the firewall bank of my 2003 AWD without pulling out the engine looks doable, but I think doing it that way potentially creates more quality control problems during prep and re-installation of the head.

 

At this point in time, it seems like it might be a good idea to try the Bar's to buy you some time.

The cooling system can be flushed when and if you end up swapping out the engine at a later date.

Good luck.

Have a good day.

 

I dont disagree with using Bar's, but it's a shame to use it on such a low-mileage engine and risk screwing up support components that may then need to be repaired or replaced if going the new head gasket route.

If I used the additive, I'd use it sparingly at first to see if it solves the problem, meaning if it says use the entire bottle, I might only use 1/2 or 1/3 of it. I realize that not using the indicated amount may not allow the additive to seal things, but.... it's a gamble either way you look at it.

 

And if I add a whole bottle, what could be the consequences? I looked at the reviews. The supplement helps some users. and what difference does it make a new or old motor, the additive works the same

 

I don't know if you remember back in early 2021 when I used K&W Fiberlock to try to quick-fix what seemed like a blown head gasket on my 2003 MO, but the stuff completely clogged up the small metal line that runs down the firewall-side of the engine to the engine's oil cooler. It turned out to be an oatmeal-like consistency. Yeah, I guess I could've just flushed the cooling system a few times until hopefully getting everything cleared out. That would entail having to be sure to disconnect smaller lines in order to adequately purge them of any additive. I don't think the cooling system would be purged on secondary lines, and it's always possible cooling jackets/ports and the thermostat could become permanently obstructed. In my case, I had only used about 40% of what I was supposed to use...

The cooling system is probably more tolerable to having additives used on it than the lubrication system, but there are still a number of things that can cause problems. Too bad it seems like such a PITA to remove the thermostat in these Muranos, otherwise I'd say pull it prior to adding the Bar's Leak, just to be safe.

 

I filled in the Bar's but nothing changed

 

With your endoscope, were you able to actually see a problem with the head gasket? Or did you simply see signs of blowby in an area of the combustion chamber? If the latter, it's possible the head has a hairline crack somewhere, in which case Bar's Leak liquid aluminum "Stop Leak" might work. I used that product in my 2003 that had a pinhole leak in the #3 cylinder cooling jacket that was visible from the exterior. It worked amazingly well and saved me from having to make an expensive repair, and it didn't become a more significant problem (if at all) until reaching 304,000 miles.

 

I did everything according to the instructions, but the white smoke remained

 

Well then, time to do a compression test on all cylinders. That gets into real work because of the transverse engine mounting.

 

Hi I want to change engine 3.5 Murano 2017

Im looking for engine, and sellers say me that I should buy only 2017, but engines 2015, 16, 17 the same

Maybe some certain ancillary components are different, such as wiring.

My question is

If you I have orig engine 2017 can I remove the auxiliary components from 2017 and install on 2016/15 change the engine to 2016/15