[photog]

we have a 2003 MO that we got back in august, have had no problems and absolutely love it. however, recently it has developed a strange whirring sound coming from engine that seems to speed up as you rev engine. any ideas what this could be?

 

[Eric L.]

Is it a supercharger like whine? High pitched like an electric motor?

If so, I think you have defective alternator bearings. It is actually a common problem with the newer Nissans with the VQ V6 engine. I suggest you take it to the dealer to check it out before you get the dreaded brake/battery light combo.

http://www.nissanmurano.org/forums/showthread.php?s=&threadid=1197

 

[photog]

thanks for the info. will get to dealer asap.

 

[photog]

sound

finally got to the dealer, turns out it is a bad fuel pump. somehow the noise is being tunneld to the front of the car from the back which is why it sounds like an engine problem. waiting for part to come in, thanks for the help.

 

[photog]

well, dealer finally got the parts in....got them installed and would'nt you believe the noise is still there! made another appointment, we'll see how that goes!

it's making a strange knocking sound that seems to shake when you first start it. anyone else have this problem? or have any idea what it could be?

 

[Eric L.]

The knocking sound is characteristic of the older VQ engines, particularly on the Maxima. On engines with over 100,000 miles, there is a bit of lifter noise on a cold start if the car hasn't been driven for a few days. Its too bad they eliminated the search function on Maxima.org (its for paying members only now), else I would provide a bunch of links on the topic. Might apply to the Murano as well since the engine is basically the same design.

It could also be knocking due to low octane fuel.

 

[photog]

well i only burn 97 octane fuel, so i don't think that is it. it's not like an engine knock it's more like a something's loose kind of knock.

thanks for the reply though.

 

[Eric L.]

well i only burn 97 octane fuel, so i don't think that is it. it's not like an engine knock it's more like a something's loose kind of knock.

thanks for the reply though.

Wow 97 octane! I don't think the VQ gets any benefit above the recommend octane which is 91.

 

[photog]

whoops! meant to say 93, don't even know where you can get 97.

 

[photog]

finally, after 5 trips to the dealer the mystery noise is solved! seems it was the fuel rail vibrating on metal that made the noise. after replacing the fuel rails the sound is gone.

might want to have these checked if you are hearing a noise that you can't figure out what it is or where it's even coming from.

 

[MO_808]

my mystery tick

sorry to dig up this old thread but has anyone else had photog's fuel rail problem.

ap13g1 (Phil) had a defective Fuel regulator valve that made his mystery ticking sound.
Like I mentioned in the other thread, my sound can be descibed as one that is similar to
when you used to put a playing card on your bicycle so that the spokes rub up against it
when riding - in turn making a cool motorcycle like sound....though not as loud AND not cool
at all when coming from the Mo's engine bay. (NOTE: this sound could be called a ticking
or rattle)

My Mo just started making the sound, i don't want to go through the
hassle of replacing the fuel pump if it's not the real problem.

any thoughts out there. I haven't been active in the forum for a while, but i'm sure glad it's here.

Aloha MO_808

 

[SIM]

MO_808, I have the same ticking sound and mine is coming from the tranny. A simple stethoscope test will indicate where the sound is coming from. Lifting the MO and simply turning a front wheel by hand will generate the sound if it is the same as mine. You can also try to rock it in neutral from the front end and you should also hear the ticking sound. Keep me posted!

 

[Eric L.]

MO_808, I have the same ticking sound and mine is coming from the tranny. A simple stethoscope test will indicate where the sound is coming from. Lifting the MO and simply turning a front wheel by hand will generate the sound if it is the same as mine. You can also try to rock it in neutral from the front end and you should also hear the ticking sound. Keep me posted!

If you can generate the sound by rotating the front wheel with the wheels off the ground, I suspect a front wheel bearing or possibly the differential.

Perhaps even a loose front stabilizer bar??

 

[MO_808]

thanks for the quick response!

Aloha Sim and Eric,

The sound is most evident at start-up - no motion involved.

Sounds like I have a cold air intake installed. If I was younger
I might have tolerated it. But I know it's not supposed to
sound like that.

Thanks for the input though.

 

[SIM]

Eric, they already went through all these diagnostic tests in my case and the noise is definitely coming from the tranny. It is quite easy to spot actually using a stethoscope. At first, they thought it was the transfer case and they changed it with no improvement. The noise comes from very close to the junction between the 2 parts.