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Discussion Starter #1
Hello
I did this a few times where i pushed teh pedal all the way to see how fast i can go to 140 kmph. each time i can smell some kind of oil burn or something burning. it goes away tho after few seconds i let go off pedal.
So i was wondering is this normal or should worry ?
Thanks
 

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Not normal, so it might be a good idea to have a mechanic look over the engine and undercarriage for visible leaks. Might also be a good idea to have them drive the car and identify the smell if possible. When you know cars, some issues can be identified by nose.
 

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Discussion Starter #3
Not normal, so it might be a good idea to have a mechanic look over the engine and undercarriage for visible leaks. Might also be a good idea to have them drive the car and identify the smell if possible. When you know cars, some issues can be identified by nose.
Thank you. i was thinking myself maybe its smell of gearbox oil. since it takes to much pressure when u go to fast.
Could anyone please try it to see if they smell such thing as well? it only happens when i floor the pedal till it reaches from 0 to 100
 

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You have an oil leak up on the top end somewhere and it's leaking down onto the exhaust,

When the engine is revved up, oil is pumped thru the engine faster, which can cause oil to pool up under the valve covers. At the same time, blow-by pressure has increased, increasing pressure under the valve covers, pushing out oil thru any little crevasse, dripping down onto the exhaust manifold, causing the smell under heavy sustained acceleration.

I would first check the PCV, which if faulty or stuck closed, will increase the blow-by pressure due to blow-by pressure not having an escape path (The PCV valve.), forcing oil out and onto the exhaust manifold. Cheapest and easiest first.

OK, not knowing the service history, it might be the oil changes haven't been regular, causing sludge to form up in the heads, affecting oil drainage. Remove valve covers. If sludge is observed, scrape and clean everything as much as possible, paying attention to the drain holes. Install valve covers and use an engine flush. I only run an engine flush for 10 minutes with the RPM at 2K, regardless of instructions to drive 100 miles or whatever. Drain, change oil filter and fill with fresh oil.

If it continues after this, then have the cylinder compressions checked. Worn rings will cause excessive blow-by, increasing internal engine pressure, causing the oil to leak under heavy acceleration. If this is the case, then either an engine rebuild or replacement is required.

Best advice? Bring it to a trusted garage/mechanic for a lookover. They should be able to spot where the oil is dripping and the make a determination on the best course of action, and how serious it really is.

Please remember these are only suggestions on a course of action. Your mileage may very. Good luck.

Have a good day.
 

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Discussion Starter #5
You have an oil leak up on the top end somewhere and it's leaking down onto the exhaust,

When the engine is revved up, oil is pumped thru the engine faster, which can cause oil to pool up under the valve covers. At the same time, blow-by pressure has increased, increasing pressure under the valve covers, pushing out oil thru any little crevasse, dripping down onto the exhaust manifold, causing the smell under heavy sustained acceleration.

I would first check the PCV, which if faulty or stuck closed, will increase the blow-by pressure due to blow-by pressure not having an escape path (The PCV valve.), forcing oil out and onto the exhaust manifold. Cheapest and easiest first.

OK, not knowing the service history, it might be the oil changes haven't been regular, causing sludge to form up in the heads, affecting oil drainage. Remove valve covers. If sludge is observed, scrape and clean everything as much as possible, paying attention to the drain holes. Install valve covers and use an engine flush. I only run an engine flush for 10 minutes with the RPM at 2K, regardless of instructions to drive 100 miles or whatever. Drain, change oil filter and fill with fresh oil.

If it continues after this, then have the cylinder compressions checked. Worn rings will cause excessive blow-by, increasing internal engine pressure, causing the oil to leak under heavy acceleration. If this is the case, then either an engine rebuild or replacement is required.

Best advice? Bring it to a trusted garage/mechanic for a lookover. They should be able to spot where the oil is dripping and the make a determination on the best course of action, and how serious it really is.

Please remember these are only suggestions on a course of action. Your mileage may very. Good luck.

Have a good day.
Thank you so much for informative things you said. I hope as you say its not inside engine.
I dont know much about mechanical stuff so i didnt understand most of what you just said.
But i have a question.. If i leave it like this, would this be ok?
Also whats the chance of it being non serious issue? cuz i already changed oils once when i got the car. just didnt want to look into this issue and tried to ignore it.
but something i know is the last owner didnt change oils much. hope it didnt damage the engine much. cuz its running very smoothly.
I love this car. Best SUV ever. i dont want to see it damaged.
Please if you have any other suggestion tell me.
Thank you very much
 

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Best advice? Bring it to a trusted garage/mechanic for a lookover. They should be able to spot where the oil is dripping and the make a determination on the best course of action, and how serious it really is.
As I said above.

Have a good day.
 

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Without hands-on, it's impossible to give an answer.

As stated above, print my first reply and bring it to a trusted mechanic or garage so that they can go thru the steps that will answer your questions.

Have a good day.
 

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Discussion Starter #9
Without hands-on, it's impossible to give an answer.

As stated above, print my first reply and bring it to a trusted mechanic or garage so that they can go thru the steps that will answer your questions.

Have a good day.
Thanks again for ur reply..
Last question just for myself to learn, U suggested me to CHeck PCV and valves myself. i searched for PCV and found out what it looks like.
Just not sure about this part and how to remove it when you said ....
"Remove valve covers. If sludge is observed, scrape and clean everything as much as possible, paying attention to the drain holes. Install valve covers and use an engine flush. I only run an engine flush for 10 minutes with the RPM at 2K, regardless of instructions to drive 100 miles or whatever. Drain, change oil filter and fill with fresh oil."
Could you please show me with a pic where is Valve cover and how to remove it?
Thx again
 

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Discussion Starter #11 (Edited)
Don't mean to be disrespectful, but if you have to ask where the valve cover is, you probably won't be able to properly remove it, and properly put it back. If you are curious, here is a video showing the removal of valve covers.
Thanks for video..
this is what he said im tryign to take notes... Could you please say what does he mean by "heads" heads of what?
"OK, not knowing the service history, it might be the oil changes haven't been regular, causing sludge to form up in the heads"
Thanks

Edit" this video is very confuing. I couldnt figure out which one is Valve cover and which one is PCV valve. And the way it looks a mechanic should do all these. i cant even change my oil, let alone removing and putting back all these parts.
So i need 2 things if u could plz help me..
1: a pic of PCV valve
2: a pic of valve cover. is valve cover under intake?
 

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First, the valve cover is the big black plastic piece At 5'24", his hand on the valve cover, and at 9'16" the removed and upside down valve cover. There are 2 valve covers on Murano engine and one of them is under the intake manifold.
The PCV valve is the white-yellowish thing on one of the valve covers. It is shown at 9'59" on the left side of the screen.
 

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Thanks for video..
this is what he said im tryign to take notes... Could you please say what does he mean by "heads" heads of what?
"OK, not knowing the service history, it might be the oil changes haven't been regular, causing sludge to form up in the heads"
Thanks

Edit" this video is very confuing. I couldnt figure out which one is Valve cover and which one is PCV valve. And the way it looks a mechanic should do all these. i cant even change my oil, let alone removing and putting back all these parts.
So i need 2 things if u could plz help me..
1: a pic of PCV valve
2: a pic of valve cover. is valve cover under intake?
Anne,

Don't make this too complicated. External oil leaks get pulled down by gravity so just get under the car with a flashlight and mirror and look for oil or oily residue around the sides and bottom of the engine. If you see something and you're not sure, touch it and see if it feels slippery. If you find something, take it to a mechanic and they'll figure out exactly what's leaking and how much it will cost to fix.
 

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Discussion Starter #14
Anne,

Don't make this too complicated. External oil leaks get pulled down by gravity so just get under the car with a flashlight and mirror and look for oil or oily residue around the sides and bottom of the engine. If you see something and you're not sure, touch it and see if it feels slippery. If you find something, take it to a mechanic and they'll figure out exactly what's leaking and how much it will cost to fix.
hi.
I had it checked by mechanic. they said the leaking is so small that its not worth opening engine. it will prolly be ok after few oil changes.
Btw i changed engine oil too. But they didnt have Nissan engine oil. SO they used Total oil. He said it has same spec of the Nissan oil.
Do you think its ok?
Thanx
 

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hi.
I had it checked by mechanic. they said the leaking is so small that its not worth opening engine. it will prolly be ok after few oil changes.
Btw i changed engine oil too. But they didnt have Nissan engine oil. SO they used Total oil. He said it has same spec of the Nissan oil.
Do you think its ok?
Thanx
As long as the motor oil meets the specifications stated in your owner's manual, it should be just fine.
 
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