Buzzing sound after TB/WP/Valve Gaskets & Drive Belts

[jpeaslee]

Summary: I did all this yesterday and today, now I have a buzzing sound that seems to be coming from the outside of the engine, seems like the power steering pump.

It's dark now and I'm calmed down. Thinking through thinks I wonder if I potentially over tensioned the power steering belt. Would this cause such a noise?


Long story, yesterday I started taking everything down to change my valve cover gaskets. Reassembled that this morning, also changing the cam plugs (sealing with a dab of rtv on the corners, reseating/sealing the half moons with rtv, changing the spark plug tube seals on the valve cover gaskets and reassembling the intake manifold, etc.

I then moved on to take everything down to do the Timing belt, water pump, idler pulley, tensioner, tensioner pulley, cam seal, power steering belt and AC belt (would have done the Alternator, but AirCabinMan on eBay sent me the wrong belt). I put in a new radiator and put my cooler in series with it while I was at it. I reassembled everything (minus the fan shroud), put in about a gallon of coolant until the radiator was full, cranked the motor.

It started up fine, I turned on the heater, and proceeded to put more coolant in the radiator. About 30 seconds in, a faint noise started to turn into a prominent, lower pitched buzz. I immediately turned the motor off and had a non clinical panic attack. Started it back up and it immediately did the same thing, and shut it back off. I thought back through EVERYTHING I did, couldn't think of what I might have done to cause this.

I started it up again to listen to where the noise was coming from, and started to calm down when it clearly isn't coming from inside of the motor/valve covers. Seems like it's coming from the front of the motor (outside the timing cover) and more towards the power steering pump.

 

[JRZEE2000TR4LTD]

Summary: I did all this yesterday and today, now I have a buzzing sound that seems to be coming from the outside of the engine, seems like the power steering pump.

It's dark now and I'm calmed down. Thinking through thinks I wonder if I potentially over tensioned the power steering belt. Would this cause such a noise?


Long story, yesterday I started taking everything down to change my valve cover gaskets. Reassembled that this morning, also changing the cam plugs (sealing with a dab of rtv on the corners, reseating/sealing the half moons with rtv, changing the spark plug tube seals on the valve cover gaskets and reassembling the intake manifold, etc.

I then moved on to take everything down to do the Timing belt, water pump, idler pulley, tensioner, tensioner pulley, cam seal, power steering belt and AC belt (would have done the Alternator, but AirCabinMan on eBay sent me the wrong belt). I put in a new radiator and put my cooler in series with it while I was at it. I reassembled everything (minus the fan shroud), put in about a gallon of coolant until the radiator was full, cranked the motor.

It started up fine, I turned on the heater, and proceeded to put more coolant in the radiator. About 30 seconds in, a faint noise started to turn into a prominent, lower pitched buzz. I immediately turned the motor off and had a non clinical panic attack. Started it back up and it immediately did the same thing, and shut it back off. I thought back through EVERYTHING I did, couldn't think of what I might have done to cause this.

I started it up again to listen to where the noise was coming from, and started to calm down when it clearly isn't coming from inside of the motor/valve covers. Seems like it's coming from the front of the motor (outside the timing cover) and more towards the power steering pump.

Fan hitting the shroud?

 

[jpeaslee]

Fan hitting the shroud?

I haven't reinstalled the shroud, the fan isn't hitting anything.

 

[JRZEE2000TR4LTD]

I haven't reinstalled the shroud, the fan isn't hitting anything.

Does it speed up and slow down with engine speed? I assume it does. Does it sound metallic or plastic sounding? Maybe start taking belts off one at a time and see if the sound goes away.

 

[jpeaslee]

Does it speed up and slow down with engine speed? I assume it does. Does it sound metallic or plastic sounding? Maybe start taking belts off one at a time and see if the sound goes away.

It does change with the engine speed, I think.

I can't say whether it sounded more metallic. Initially I thought it did, but I think that because I thought my cams were grinding for some reason. I wasn't thinking straight at that point.

I think my plan at this point is to (in the morning, with good light) give everything another good visual inspection, then loosen up the PS belt and go from there. If that doesn't work, I'll start taking the belts off and see if the sound goes away. Is there a quicker way to take belts off other than taking the fan off? That thing is a real SOB to get off with my fat fingers/hands.

 

[jpeaslee]

Ok. so I loosened the drive belts and had the same noise. Took off the timing belt cover and confirmed it wasn't coming from there and everything looked good underneath.

Took off the drive belts/pulley and Fan, and voila! noise gone. In doing this I noticed the fan support was really hot. Anyone know if it normally runs hot? I wasn't running the car for more than a few mins. Could I have jacked up the bearing in there, causing the noise? Thinking about it, it really does sound like a bearing.

I'm going to reinstall it with just the alt belt and see if the noise is still there since the sound is definitely not coming from the right side of the engine.

 

[Unner]

Take a long screwdriver or pry bar or something and put it on the fan bracket, alternator, power steering pump, etc and put the handle end up to your ear. You'll easily be able to pinpoint which one of them is making the noise. Just be careful sticking things in the engine bay and putting your ear up to it... This worked 100% each time I had to diagnose my alternator with bad bearings (Stupid Chinese parts). You'll be able to hear the bearings grinding in the one that's malfunctioning, and the ones that are fine will sound smooth. Good luck!

 

[jpeaslee]

UPDATE: Problem Solved!

It's the a/c idler/tensioner pulley. Don't know how it went bad just taking it off and putting it back on during all this, but it did. A little WD-40 made it a bit quieter, but I'll get another one ordered. So relieved that's all it was. Thanks for the help!

Also, I should have mentioned that I used a wooden dowel as a mechanic's stethoscope and it just about confirmed without a doubt that's what it was before I started taking everything down, I don't know why I didn't just trust my instinct.

Also, for anyone else having similar symptoms, save yourself a lot of work and just take the pulley off and leave the fan and all the belts there. It'll run fine without causing issue and it will quickly confirm your diagnosis.

 

[jpeaslee]

Take a long screwdriver or pry bar or something and put it on the fan bracket, alternator, power steering pump, etc and put the handle end up to your ear. You'll easily be able to pinpoint which one of them is making the noise. Just be careful sticking things in the engine bay and putting your ear up to it... This worked 100% each time I had to diagnose my alternator with bad bearings (Stupid Chinese parts). You'll be able to hear the bearings grinding in the one that's malfunctioning, and the ones that are fine will sound smooth. Good luck!

Just noticed your post. That's always the first thing my grandpa asks, "did you take a piece of wood or pipe and listen to it?" I like wooden dowels the best, zero chance of sparking/shocking anything, and if somehow I got it caught in something seems like it'd be less damaging than something metallic.


You back in this part of the south, or are you still in NC?

 

[Unner]

Just noticed your post. That's always the first thing my grandpa asks, "did you take a piece of wood or pipe and listen to it?" I like wooden dowels the best, zero chance of sparking/shocking anything, and if somehow I got it caught in something seems like it'd be less damaging than something metallic.


You back in this part of the south, or are you still in NC?

Glad it was an easy fix! It's no fun when the truck starts making new noises...

I'm in SC for the summer, but I'll be back down in Alabama come August time frame. We'll have to meet up sometime. Looks like your trailer is coming together nicely too!

 

[185Runner]

Just an FYI. You don't have to remove the fan to change your belts. You can feed them around them fan. Just go slowly and do one blade at a time. It's way easier and faster than removing and reinstalling the fan Everytime.

 

[jpeaslee]

Welp, no issues sitting in my driveway, but 2 mins down the road and I threw a CEL. P0325 Knock Sensor 1 Circuit Bank 1, P0330 Knock Sensor 2 Circuit bank 2, and P0340 Camshaft Position Sensor "A" Circuit Bank 1 or single sensor.

Did I miss a plug somewhere? Any thoughts?

 

[amalik]

Wow man. You did all that work in one day?


Sent from my iPhone using Tapatalk

 

[Unner]

Welp, no issues sitting in my driveway, but 2 mins down the road and I threw a CEL. P0325 Knock Sensor 1 Circuit Bank 1, P0330 Knock Sensor 2 Circuit bank 2, and P0340 Camshaft Position Sensor "A" Circuit Bank 1 or single sensor.

Did I miss a plug somewhere? Any thoughts?

Did you plug in the cam shaft position sensor? It's right by the power steering pump. I'm not sure if it would run with that unplugged, but it's worth a check.

 

[jpeaslee]

Did you plug in the cam shaft position sensor? It's right by the power steering pump. I'm not sure if it would run with that unplugged, but it's worth a check.

I did. I just got back from lunch. I unplugged and replugged it to make sure it' was in there good. Cleared the codes, ran down the road, both knock sensor codes popped back up, but the timing code didn't. I drove a few miles down the road and the cam sensor stayed cleared.

So it seems as though it's just the knock sensors. I'm going to take the manifold back off and visually inspect everything. I do remember now that when I took everything off before doing the valve cover gaskets, the plastic cover over the harness broke off in a couple places (it was really brittle). I'm going to inspect it too and make sure I don't see any cuts or pinches in the harness.

 

[Unner]

I did. I just got back from lunch. I unplugged and replugged it to make sure it' was in there good. Cleared the codes, ran down the road, both knock sensor codes popped back up, but the timing code didn't. I drove a few miles down the road and the cam sensor stayed cleared.

So it seems as though it's just the knock sensors. I'm going to take the manifold back off and visually inspect everything. I do remember now that when I took everything off before doing the valve cover gaskets, the plastic cover over the harness broke off in a couple places (it was really brittle). I'm going to inspect it too and make sure I don't see any cuts or pinches in the harness.

It's possible the wires to the knock sensors got distrubed while you were in there and broke since they can get brittle due to age and heat. Looks like you can get a new OEM harness for them if that is the case. [MENTION=116467]Rock_Rat[/MENTION] has a good thread on the subject.

http://www.toyota-4runner.org/3rd-g...-everything-replaced-puzzled.html#post1880069

 

[jpeaslee]

It's possible the wires to the knock sensors got distrubed while you were in there and broke since they can get brittle due to age and heat. Looks like you can get a new OEM harness for them if that is the case. [MENTION=116467]Rock_Rat[/MENTION] has a good thread on the subject.

http://www.toyota-4runner.org/3rd-g...-everything-replaced-puzzled.html#post1880069

I was thinking along the same lines, for both sensors to go bad simultaneously seems more like it'd be that harness. Turns out if you don't plug the harness back in, you'll throw two knock sensor codes.

Apparently when I was moving the harness around to get the valve covers out, the plugs tucked up under the lip of the timing cover and I didn't plug them in... Plugged it back in and everything went to working like normal!

 

[Unner]

I was thinking along the same lines, for both sensors to go bad simultaneously seems more like it'd be that harness. Turns out if you don't plug the harness back in, you'll throw two knock sensor codes.

Apparently when I was moving the harness around to get the valve covers out, the plugs tucked up under the lip of the timing cover and I didn't plug them in... Plugged it back in and everything went to working like normal!

Good thing that was an easy fix too. Now you should be set for awhile on maintenance. When I did my valve cover gaskets I missed one of the plugs on the back of the throttle body. Happens to everyone haha.