Help identifying engine sound

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Joined
Jan 30, 2023
Threads
2
Messages
11
Location
California
Hey guys,
I’m trying to track down the culprit for this sound. Sometimes it’s louder than others. Only heard it at idle and when parked. Was talking with @Mike NXP about it maybe being a fan bearing? Power steering pumps been whining as well.
 
Only reason I put the phone through the wheel well was because hood was closed and didn’t want to miss it, does sound like passenger side. Has new timing belt, water pump, tensioners, radiator.
 
It's too hard to tell from the video but I can hear some sort of metallic grindy noise so my guess is a bearing is failing somewhere.

You'll just need to stick with the troubleshooting path for belt noise that we chatted about. Otherwise it will be a guessing game until it gets way worse / fails.

  • Remove accessory belt
  • Inspect belt for debris, cracks, oil, etc.
  • While removing, feel the tensioner. It should have plenty of resistance / spring but it shouldn't be getting bound up or feel choppy at all. A nice smooth tensioner with decent resistance is what you want to feel

  • Now that the belt is off, did the noise go away?
    >> If Yes, we can focus on accessory pulleys
    >> If No, then you are going into the timing belt components.

  • You mentioned you just did the timing belt kit and water pump
    >> Did you use OEM?
    >> Who installed it?
    >> Did the problem start after the recent work?

  • Assuming timing belt and all that checks out you can focus back on your accessories.

  • Power steering and AC are probably your least likely culprits

  • Check the fan for a smooth spin and give it a wiggle to help diagnose fan clutch / fan bracket failure.
    >> My fan bracket was squealing like a banshee on cold mornings but it didn't have any play
  • Use a stethoscope to poke around the fan bracket / AC area and listen. You shouldn't hear any noise.

  • Check idler pulley x2 and tensioner discussed earlier
    >> There is a good chance these need replacement if they are original
    >> You want a smooth spin without any free spinning. Maybe 1/2 - 1 turn if you spin the pulley. Any noise or free spin , need to replace.

  • If all the checks out , put the belt back on and fire it up
  • Get a stethoscope and poke around the AC / Fan bracket area again to see if you can hear it now
  • When my fan bracket bearing was failing I was able to hear the noise reverbing throught the driver side / lower area near the AC
 
Thought I would update this, this seems to be quite the mystery. Fan bracket and bearing replaced, new power steering pump, new reservoir and upper lines. No fix.
Brought to Toyota to diagnose, they determined it was the alternator making the noise, which was new. They replaced the alternator and the noise was still present. Toyota says the sound is normal, I am not sure what else to do.
 
Thought I would update this, this seems to be quite the mystery. Fan bracket and bearing replaced, new power steering pump, new reservoir and upper lines. No fix.
Brought to Toyota to diagnose, they determined it was the alternator making the noise, which was new. They replaced the alternator and the noise was still present. Toyota says the sound is normal, I am not sure what else to do.
Tell me more about the fan bracket and bearing replace . Who installed it, did you go with OEM parts?

Gotta understand Toyota isn't willing to chase down issues like this , it's not worth their time.
 
Do or can you check and change stuff, like: Oil, coolant, air filter, etc? If so I may be able to help you diagnose.

If not, take an get second or even third shop(s) opinion. Local INDY shop that work on all makes and models, 90% of them do more harm than good. Take to 100 series specialist or Toyota/Lexus Dealerships.
 
Well I'm not sure, are you sure they changed the fan bracket deep within and not just the fan clutch??

The grinding / scratchy noise heard in the first video are not normal. Really any noise other than your fan roaring shouldn't be heard.


I'd have to point you back to my original steps of troubleshooting belt noise by removing and inspecting each pulley. I can help walk you through it if you need.
 
Do or can you check and change stuff, like: Oil, coolant, air filter, etc? If so I may be able to help you diagnose.

If not, take a get second or even third shop(s) opinion. Local INDY shop that work on all makes and models, 90% of them do more harm than good. Take to 100 series specialist or Toyota/Lexus Dealerships.
That would be awesome.
 
Well I'm not sure, are you sure they changed the fan bracket deep within and not just the fan clutch??

The grinding / scratchy noise heard in the first video are not normal. Really any noise other than your fan roaring shouldn't be heard.


I'd have to point you back to my original steps of troubleshooting belt noise by removing and inspecting each pulley. I can help walk you through it if you need.
When Toyota ran with the belt off they said the noise went away.
 
Here's what I'd do:

First with a cold engine, hood open and engine cover off, (before stating 1st check of fan clutch) I start engine. Trying to detriment general area of sound i.e front side(s), top or rear of engine. Which most common is front. So I'd take a $5 Harbor Fright stethoscope and check for any chirps, oscillating, sandy or grinding sounds. Being care not to get loose clothes, finger or tool caught in any moving parts. Listen to: Idler pulley (on blot head), tensioner pulley (on bolt head) and fan bracket bearings (on body/case/housing behind pulley/belt). I'd also check the alternator (on body/case/housing, don't short if contacts exposed), vane pump (on body/case/housing) and AC compressor (on body/case/housing). Look also to see if fan bracket pulley jumps or wobbles as in spins, in conjuction with sound.

I'd check fan clutch for proper operation before starting engine and as engine warms up, while I'm listening with stethoscope.


Next I'd remove fan belt do more checks. While removing belt, by way of tension 14mm left hand bolt. Note pull of tensioner, it should pull against you strong (about 12lb)


Then while fan belt off. Start engine. Is sound still present at front of engine. Then I'd suspect it's from Timing belt or it's pulleys or water pump.

Also worth a note, a wonky of partially stuck PCV valve of bad vacuum lines/hoses. Can make stranger sounds. So do inspect them.

Also inspect air filter, make sure in good condition and that it's rubber seal is good (not curled). Also air pipe to throttle body connected properly, making perfect seal 360 degrees (underside I find curled, all to often).

Also look very close at any work done, just before sounds started.

If all checks-out, as good. Hose fan belt with water, while engine running. Does it squeal as water drys. Replace the fan belt with OEM.
 

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