Weird noise after timing belt replacement

Hi,

Certainly, something could have come loose or failed. There is actually a timing belt tensioner under the cover. It may have failed or started to fail allowing slack in the belt.

This tensioner is an automatic tensioner, so it would need to be replaced and not physically adjusted. I attached a pic below so you can see what it looks like.

Here is my biggest concern. If in fact the belt is becoming loose or something is failing, it can cause major internal engine damage if the belt jumps timing, breaks, or falls off. This is an interference engine and if the timing is off, there isn't enough clearance between the tops of the pistons and the valves in the open position. If it fails, usually the result is bent valves and cylinder head and or piston damage. Because of that, I would recommend taking it back and having it checked.

Let me know if this helps, what I can do to help, or if you have other questions.

Take care,

Joe

I drove it again today and didn't notice the noise upon first startup, but I did notice it after driving for a bit then stopping and opening the hood. So, the noise only happens after warmup it seems.

When I got home today my neighbor brought over his stethoscope and the noise is definitely coming from under the timing belt cover. I've made an appointment back at the dealer to have it checked. It's a bummer if they take it all apart and it's not something they did, then I got to pay the labor for disassembly and diagnostics...

Hi,

If that is where the noise is coming from, something needs attention. We have two ways to attack this. First, have them listen to confirm that is where the noise is coming from before taking things apart.

Or I attached a pic below. It shows the two upper timing belt covers and the bolts holding them in place. You could remove those and check belt tension by hand and with a flashlight, look down into the bottom cover to see if anything appears loose or damaged.

This should be all that is required of them to do for confirmation. You will likely need to remove the serpentine belt and a few covers, but it really isn't that difficult to do.

Let me know if you have questions or if I can help in any way.

Take care,

Joe

See pic below.

Dealer took the cover off and the timing belt and tensioner are fine. They said it's the serpentine belt tensioner making noise. That wasn't part of the timing belt package (but the actual serpentine belt was). How difficult is it to replace the tensioner myself?

Hi,

It's interesting that it didn't start until after the work was done.

Regardless, the worst part of replacing this is room to work. You will need to remove the belt and then the plastic splash shield under the front. It is held in by several different plastic clips.

If you look below, I included a pic of the tensioner (pic 1) showing which way to move the tensioner to loosen the belt. Remove the belt first. Next, pics 2 and 3 explain how to remove the splash panel. If you find access without removing the entire thing, that is fine.

The last pic shows the tensioner and directions. There are two bolts that need to be removed for the removal of the tensioner. The installation is the opposite of removal.

Let me know if this helps or if you have other questions.

Take care,

Joe

See pics below.

Yeah, it is kind of fishy, but it did wait nearly 3 weeks before showing issue so maybe it was happenstance? I did go out today and physically try to wiggle the serpentine tensioner and the topmost pulley on the tensioner did make a single "click" sound when I wiggled it up and down. So maybe that is indeed the problem?

The tensioner serves two functions. First, it keeps the belt tight to prevent slipping. Second, it houses (in this case) two pullies that the belt rides on. Each one of the pullies has a bearing that can fail.

If the belt seems tight, it may just require one or both of the pullies to be replaced. The only way to check is to remove the belt. Once it is off, spin the pullies to see if they make noise and wiggle them side to side and up and down to check for play.

If you could record the sound and upload it for me to hear, I should be able to direct you better.

Let me know.

Joe

You have to listen very carefully it's almost inaudible over the engine itself, but it's there...

Hi,

I hear something but as you said, it's hard to notice. If it was my vehicle, I think I would drive it like that because nothing sounds like it is ready to fail. Once it gets a little louder, then you can pinpoint exactly where the sound is coming from.

If you would feel more comfortable checking, then I would suggest removing the belt and spinning one pulley at a time to see if you hear the sound.

Let me know what you find or if I can help in any way.

Take care,

Joe

I'm thinking that as well. Most times I've heard a tensioner go bad it squeals really bad, so I'll just drive until I hear more noise. Worse case if it does fail I'll just lose power steering and alternator and need a tow back home for repair.

Hi,

If the tensioner would lose its strength, you are correct. The belt will likely start to squeal. If it is one of the bearings failing, it will just get louder until it ultimately locks up, but you will likely hear that happening long before total failure.

If possible, let me know how it is after a week or two. If it does get louder, upload a recording so I can hear it.

Take care of yourself and let me know if I can help in any way.

Joe

Okay, now today I've noticed a loud chattering coming from under the hood when the A/C is on. If I turn it away, the chattering stops. Could this be related to the tensioner or something else?

Hi,

If it is the tensioner, you should be able to tell in one of two ways. With the engine off, grab the belt and see if it has any play. It should be tight. Or open the hood and turn on the engine and A/C. Use a flashlight to see if the tensioner is jumping around which would indicate it is likely bad.

If you can, record it and upload it for me to hear. Hopefully, I recognize the sound,

Let me know.

Take care,

Joe

I noticed when I was in the drive thru with the window down, but once I got to where I was going and opened the hood, the noise was gone (except for the original sound I started the thread for). If I hear it again, I'll try to record it...

Hi,

Sounds good. If it happens again, try to inspect the tensioner before turning it off.

Let me know what I can do to help.

Take care,

joe

Okay, my neighbor came over and we looked everything over. Belt tension is good, no clicking or movement in the belt. We've narrowed the noise down to the motor mount. I put it in drive and reverse with foot on brake, and when I hit the gas, he saw the mount move and we heard the chattering sound a bit. So, I guess the motor mount is on its way out the door...

I went back and checked through the maintenance records, that same motor mount was just replaced around 40,000 miles ago at the dealer. I wonder why it would break so quickly, unless they messed it up somehow when they changed the timing belt?

Hi,

In most cases, a motor mount will last the life of the vehicle. Which one moved? How far did it move? Does it move in drive and reverse?

Here is a link that explains in general how one is replaced. Take a look through it and let me know if it helps.

https://www.2carpros.com/articles/replace-motor-mounts

Take care,

Joe

The passenger side motor mount is where we were looking since that's where the noise comes from. He said it shifted inside the mount in both forward and reverse when I pressed the gas and we heard the chatter when I pressed the gas as well.

Some movements are normal because it is mounted in rubber. However, rattling isn't. If you feel that is where the noise is coming from, then it certainly is a possibility.

Do you plan to replace it yourself or have the dealer do it again?

Let me know what I can do to help.

Take care,

Joe

I may go out there tomorrow and just re-tighten all the bolts on the motor mount just to be sure the dealer didn't miss something when doing the timing belt.

I would try to replace it myself for sure, it's a $25.00 to $30.00 part. But before I do anything I want to listen with the stethoscope again just to be double sure before buying anything. That's the only thing we didn't do today was stethoscope.

Hi,

That is a good idea. Let me know if it is the problem. Also, I attached the directions specific to this vehicle for replacing the front engine mount.

Let me know what you find or if I can help.

Take care,

Joe

See pics below.

I finally managed to get a video of the chattering. I had to drive it for a while with the AC going, then stop and out the parking brake on (but leave it in drive). If I put it in park or turn off the AC, the chattering stops.

Hi,

It sounds like the tensioner is chattering, which is very possible, or the A/C clutch is kicking on and off.

I attached a pic below. The highlighted part is the belt tensioner. Check to see if that is vibrating when this is happening.

Next, in red, I circled the A/C compressor. At the front of the pulley is the clutch. With the A/C off, the pulley spins freely. When you turn the A/C on, the clutch clicks in and turns the compressor. Check to see if that clitch is kicking on and off. Here is how you can tell:

The center of the pulley will not be turning with the AC off. When it's on, the center will engage and turn. If you look at pic 2, in red I circled the clutch. With the AC off, that will not turn while the pulley does. When turned on, that engages and begins to turn with the pulley.

Let me know what you find or if you have other questions. Also, if I had to guess, I would say the tensioner is the issue and not the compressor clutch, but since it stops when turned off, that is where the sound may be coming from as well.

Take care,

Joe

See pics below.

Can I just replace the idler and tensioner pulleys, or do I need to replace the entire assembly? I saw where they sell the individual pulleys for way cheaper than the assembly.

Hi,

Each of the pullies has a bearing. If the bearing was bad, yes you could do that. However, I'm questioning if it is the tensioner itself. It could also be caused if one of the other belt-driven accessories is faulty.

What to do is remove the belt and spin all the belt-driven accessories to make sure none are tight or make noise. Also, take note if there is any play up/down, side to side, in and out on the pullies.

If everything seems good, then suspect the pulley assembly needs to be replaced. Take a look at Rockauto.com for pricing. Usually, they offer the best price.

Let me know if I can help.

Take care,

Joe

Yes, I plan this weekend to relieve the tensioner and check all the items it connects to. I've already been looking at RockAuto the prices range from $50.00 to $150.00+. What's the difference?

Hi,

Often times the brand is causing the cost difference. As long as it is for your vehicle, you shouldn't have any trouble. If you find something inline by a private seller that is nameless, be careful. There have been a lot of after-market parts that last a day if you're lucky. LOL

Let me know what you find or if you have questions.

Take care,

Joe

Okay, we've definitely narrowed it down to the tensioner. I've noticed it even chatters a bit when the A/C is off and I'm turning hard or even right when I press the gas to take off. Sounds like any extra load on the tensioner causes chatter. And if you pull on the belt slightly you can hear the spring inside click.

Hi,

If you hear a clicking, that does sound like the issue. Have you replaced it yet?

Let me know.

Joe

No, I haven't ordered the part yet. How much longer do you think it will last, considering how it's sounding in the video I posted earlier?

Hi,

That's a really hard question to answer. It could last another 6 months or 6 minutes. LOL However, the belt will likely start squealing prior to total failure. Pay attention to that.

Let me know how things turn out for you.

Take care,

Joe

Well, I did see kits on rockauto that had the belt and tensioner together, lol.

Hi,

That's usually the least expensive place to get them. Also, when checking out it will ask where you learned about them. Use this code and you'll get another 5% off.

203171354183710334

Let me know what I can do to help.

Joe

I replaced the belt tensioner today and so far the noise is gone!

Hi,

Thank you for the update. I'm glad to hear it's fixed.

Please feel free to come back anytime in the future. You are always welcome.

Take care,

Joe

Question. I've noticed that the belt is riding off center on the tensioner pulley. It's not coming off, but it's like 1mm close to the edge facing the wheel. Will this cause any issues? My neighbor who used to be a mechanic said the belt said as long as it's on the pulley it's fine.

Hi,

He is correct, but I would rather know it's centered. Do me a favor. Just keep an eye on it to see if it changes at all.

Let me know if there is anything I can do to help. Also, if you want to take a pic of how it is and upload it for me to see, I would be happy to let you know my thoughts.

Take care,

Joe

I haven't noticed it move at all. I think it's just that we barely got the belt on there due to the new tensioner being so tight and hard to move. We figured it would self-center but I guess not. I might try to relieve the tension and slide the belt over some more of I can.