[aegrotatio]

My nearly perfect 2007 Frontier is starting to emit a loud, high-pitched buzzing whine. It seems to be independent of engine speed. It turns on and off. It actually sounds like the fuel pump on my old GMC truck, a flanging piezo buzzer sound, but those don't turn off on the GMC.

What could it be?

It's a 2007 Frontier LE 4x4 crew cab, short bed, 4.0 V6, with no off-road bits.

 

[Clint]

Does it do it at idle? If it does maybe remove the fan belt to see if that eliminates it. Maybe it's the idler pully. The timing chain issue doesn't stop and does fluctuate with the engine speed.

Clint

 

[aegrotatio]

Thanks for the quick advice!
Here is my troubleshooting:

It's a humid day around 38 degrees.
It makes the sound at idle and while revving but is a constant pitch and volume.
It is not activated by A/C compressor, nor by alternator load (turning on heated seats and defroster).
Turning the steering wheel doesn't make it come back or go away (thinking steering pump).
Pumping brake does not make it come back or go away (thinking brakes).
Shifting in and out of gears doesn't seem to have any effect (thinking tranny).
The noise is loudest in the wheel wells and underneath the front end.

When the sound does go away (and I haven't found how) if I push the accelerator, the noise comes back.

 

[Clint]

There is a bearing in the idler as well as the water pump which you couldn't test for by what you did.
How does the fan belt look?

Clint

 

[aegrotatio]

Interesting. The belt is fresh as a baby's bottom.
I'm thinking water pump.
Sorry if I sound silly, but is there an oil pump?

I'm bringing it in for burnt-out seat heater warranty fix this month so I'll add this to the list of complaints. I normally do spur-of-the-moment Jiffy Lube since the mileage isn't high enough for the big work yet.

Am I the only one who hates it when the service writer writes down "customer complains of..." all over the service order?

 

[1stNISSAN]

sounds like the fabled timing chain guides.

 

[dubie2003]

I would highly recommend that you remove the belt first and see if the noise is still there. I know you tried some thing as a test but removing it will be the definitive answer to if it is an accessory or an internal issue.

 

[devious1]

Agreed to removing the belt, if it stops, water pump or alternator pulley. Its a simple check.

 

[aegrotatio]

Thanks so much for the advice. I honestly don't know (or want to know) how to remove a serpentine belt so I was just looking for some good advice to listen for when they give me their diagnosis.

Thanks again, guys!!

 

[dubie2003]

I know you said you didn't want to know how to remove the belt but it is easy. Use a 3/8ths ratchet in the tenioner and move it to the side to put slack into the system. Then slide it off and you are good to go. The crappy part is that you have to move it around the fan so wear gloves and possibly long sleeves.

This is the only way to see for sure if it is accessory related or not. Also, usually its a bearing that goes bad so even thou there is no increased load on an object, it will still squeal.

 

[mouse]

Thanks so much for the advice. I honestly don't know (or want to know) how to remove a serpentine belt so I was just looking for some good advice to listen for when they give me their diagnosis.

Thanks again, guys!!

Before you take off the serpentine belt I would just take the truck into the dealer and ask them to check and see if it is the time chain guides. I just did this the other day on my 2007 SE and they were able to tell me I needed new guides and a new chain in about five minutes with the truck. It didn't cost me anything to have them check it and since my truck is under 60,000 miles they are going to warranty the fix. Good luck.. If you feel like it maybe the serpentine belt you could take it off and it isn't really too hard to do, just takes some time.

 

[Clint]

Before you take off the serpentine belt I would just take the truck into the dealer and ask them to check and see if it is the time chain guides. I just did this the other day on my 2007 SE and they were able to tell me I needed new guides and a new chain in about five minutes with the truck. It didn't cost me anything to have them check it and since my truck is under 60,000 miles they are going to warranty the fix. Good luck.. If you feel like it maybe the serpentine belt you could take it off and it isn't really too hard to do, just takes some time.

Some dealers will threaten you with a one hour labor charge if it's not a covered item. So it's free under the 5/60 if it's the chains but if it's something else like pump or alternator and not covered you're either out that money or have to have them perform the repair.

Clint

 

[aegrotatio]

I finally bothered to claim this on my warranty, which is two weeks until expiration, and the winner is: pretension belt pulley.

Thanks to you all for your assistance. Initially the dealer write-up guy was as baffled as I was, but evidently a tech took a closer look and confirmed it's the belt pretensioner.

For what it's worth, it sounded exactly like a GM fuel pump buzz but about 100x louder (and from the front end). I heard that GM solved the noise problem by dunking the fuel pump in the middle of the fuel tank to silence the noise from that cheap fuel pump.

 

[aegrotatio]

It's now 2014 and the buzzing has returned but it's much quieter. I suspect whatever the rubbing parts are will burnish itself out over time.

A rule of thumb that's held true since 1993 has shown me that cars, in general, don't last more than seven years before having serious problems.

 

[lowEnuff]

hey aegrotatio any chance you have the part number for the pretension belt pulley?
I noticed ny 2006 having this noise in the last days comes and goes.
Also anyone know if this is a job one can do themselves???

thanks,

 

[bob-w]

are you sure it isn't the electric aux fan - it has 2 speeds and can sound like whine. If it is turning on check your coolant level.

 

[lowEnuff]

thanks Bob I will check that out today !!

 

[xtopherfishing]

Cancel message, I failed to read later comments on the fix.

 

[madmat]

mine has the same high pitched whine.thought fuel pimp at first going to chect the pre tensioner and see if this prob thanks.

 

[frontierbill]

Find a flexible hose (like a garden hose) and cut a short (3 to 5 ft) section and put it up to your ear while pointing the open end closely toward the sound. You can pin point many problem sounds much quicker and eliminate the guessing. I have used this method for 60 years and it works.