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Noise Paranoia! PS Pump? Idler Pulleys?

9761 Views 13 Replies 9 Participants Last post by  4g63t666
Noise paranoia. We all have it. I might be suffering from delusions.

Anyway, over the past 10K miles (currently at ~54K) or so, I've noticed a "whirring" noise coming from the passenger side of the motor. My thoughts:

  • Noise is most priminent between 1000 and 3000 rpms at partial throttle. Mostly during cruising in any gear. Beyond those engine speeds and under acceleration, engine and exhaust sound drown out the whirring.
  • I've ruled out the transfer case as the noise is RPM based and not velocity based.
  • I've ruled out the transmission as the noise would then be either on center or driver side.
  • Possibly the power steering pump. However, noise does not increase with steering input. It might increase with engine load but that is tough to tell as the amplitude of all other noise increases as well.
  • Possibly the idler pulleys? Ive checked these out and looks like they have wear similar to what ive seen at this mileage. Accessory belt does not look overly worn, about standard for this mileage as well.

Any thoughts, guys?
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change out ps fluid to atf instead of that crap mitsu stuff- if the noise goes away then it was the ps pump. If not then look at the plastic idlers.
easiest way to narrow it down.
change out ps fluid to atf instead of that crap mitsu stuff- if the noise goes away then it was the ps pump. If not then look at the plastic idlers.
easiest way to narrow it down.
That was the plan, just in reverse. I already have a new belt and pulleys for the next major service, so i was gonna do those first since i have to do them anyway. Then replace the PS fluid if the noise doesn't disappear.

What makes the Mitsu stuff crap?
That was the plan, just in reverse. I already have a new belt and pulleys for the next major service, so i was gonna do those first since i have to do them anyway. Then replace the PS fluid if the noise doesn't disappear.

What makes the Mitsu stuff crap?
They market it as oem fluid that has to be run or else .

ATF lubricates everything better, it was designed as a high pressure hydraulic fluid. and its way cheaper
They market it as oem fluid that has to be run or else .

ATF lubricates everything better, it was designed as a high pressure hydraulic fluid. and its way cheaper
OK. Ill look into it. You didnt really answer my question though...The mitsu fluid might just be ATF.

Have you replaced yours? Is the ATF viscosity higher than the OEM fluid?
Mitsubishi power steering fluid is just atf according to the owners manual. Wouldn't hurt to top it off or flush it out with new stuff. My PS pump starts whinning if the resorvoir isn't all the way at maximum, but only when I turn the steering wheel.
OK. Ill look into it. You didnt really answer my question though...The mitsu fluid might just be ATF.

Have you replaced yours? Is the ATF viscosity higher than the OEM fluid?
I use ATF F - and yes, mitsu fluid is atf as well. no clue on viscosity,

I replace mine at least once a year
That seems like common Oil pump noise - get's louder when oil get's older, after oil change it's somewhat better but goes back to same noise level once oil get's older again.

My dealership said it's designed that way :/ I have 40k miles - noise was since day 1 and didn't change much.
do you need to replace a new oil pump if you car has this noise. a new pump might also has the noise as its getting old. is this a defective or the car will be okay to drive with old pump.
That seems like common Oil pump noise - get's louder when oil get's older, after oil change it's somewhat better but goes back to same noise level once oil get's older again.

My dealership said it's designed that way :/ I have 40k miles - noise was since day 1 and didn't change much.
Its not oil pump. Recently changed the oil with no difference in sound. I'll be replacing the idler pulleys and belt as soon as a get a couple free hours. I'll check back in when complete.

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That seems like common Oil pump noise - get's louder when oil get's older, after oil change it's somewhat better but goes back to same noise level once oil get's older again.

My dealership said it's designed that way :/ I have 40k miles - noise was since day 1 and didn't change much.
Same here. Less miles but same experience.
subd for results. I literally have the same exact noise/ (issue?) going on
CanEvo already said it... It is most likely your oil pump noise.
Is it similar to this noise? ( the video is a little extreme, mine was only this loud if my oil change is over due)
http://youtu.be/F8qry6HutYQ

If it is similar to this, then it is your oil pump noise, get your oil changed , it will quiet down a lot.
Did the idler pulleys do the trick? I've got the same annoying problem here
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