Strange noise (goes away after alternator belt removed) NOT alternator or belt

2003; 2.4L; stock; 161k mileage.

It's been about two months with the noise. After start up, it goes away after 5-10 minutes of driving or idling. I had a hard time getting it looked at because after sufficiently warmed, the noise goes away. It takes a couple hours of rest to come back. The noise increases with acceleration at idle.

My mechanic removed one belt at a time, checked A/C, and steering. Narrowed it down: Noise went away after alternator belt removed. Replace belt. Didn't fix. Replaced alternator. Didn't fix. He put my old parts back on and didn't charge me. Said he couldn't diagnose and to continue driving because it's not effecting performance.

Any ideas? Thanks!

 

I'd suggest finding a new mechanic. If he had a mechanic's stethoscope he should be able to quickly find where the noise is coming from.

 

My guess would be the water pump bearing.

 

I might try somewhere else. He's been my trusted mechanic for over a decade. Never overcharging or selling me things I don't need. I'm hoping the fact that it was a busy Saturday prevented him from fully exhausting all options. He did mention wanting to look into the water pump and crankshaft pulley, but not having enough time.

 

Thanks for the info and the video, sounds like a pulley. If he narrowed it down by finding out which belt was causing the noise, that's a great start. Which are the pulleys used by that belt? Do you have a longer wooden dowel or long flat screwdriver you can use as a stethoscope of sorts? You obviously have to be very careful when you do this, but that could possibly tell you very quickly which is the noisy pulley.

 

Forgive my ignorance on this, but I believe it's the alternator pulley. My mechanic methodically removed belts and asked me to start up, all the while checking A/C and steering wheel. Once the alternator belt was removed, the sound went away. Neither replacing the alternator or belt removed the sound. Possibly an alternator pulley or bearing?

 

New alternators come with a new pulley and bearing, so you've already ruled those out.
That belt also drives the water pump and fan/clutch, so it must be one of those.

The fan clutch would be easy to eliminate.

 

Exactly what this guy ^^^ said. Good post.

 

I'll test the fan clutch today and report back.

 

It's not the fan clutch.

 

Take the belt off and wiggle the water pump pulley and check for play from side to side. Also turn it while putting pressure on it like the belt would and see if you can feeling grinding. I'd say with everything you've listed so far the water pump sounds like your next suspect and if that's the case it will have an effect on performance in the near future if not already.

 

Update: Dropped it off at World Toyota in Atlanta this morning, and they shuttled me to work. Got a call saying I needed a new water pump and fan clutch. Price $1278.24. $670 for parts, the rest for labor. Seems excessive doing a basic Google search for those parts. Thoughts?

I'm waiting for them to fix a spare tire recall, and come and pick me up. They want a deposit on the parts since they have to be ordered. Should I have someone else do the fix for cheaper? I'm currently waiting on my other mechanic to call back to give me a quote on this fix

 

My mechanic said he would charge $526.80 for the repairs, but no guarantees on a fix, and no returns on the water pump, given the extent of the fix.

I'm sadden by my '04 Tacoma that was totaled earlier this year due to someone running a red light. Same truck, but 220K miles with no major problems.

 

I would tell them to kiss your ass. That is outrageous. $670 in parts?????? Are they gold plated?
Look online and buy the parts. Install them yourself or look locally for a small shop mechanic. $608 for labor? Holy smokes. Run from that dealership.

 

If your are mechanically inclined........you can replace the water pump and the fan.

 

tensioner?

 

Like said before, get the parts and find someone to install them if you can't. Those prices are why I got an extended warranty when I got my truck, up to 100,000 miles anyway, then I start turning wrenches again. I wouldn't mess around replacing that fan clutch, turned out to be the cause of my AC failure in my precious truck. The freon returning to the compressor was way to hot and melted the rubber shaft seal, because the fan wasn't spinning fast enough when stopped in traffic.