What's this sound from the alternator area?

[speedster]

Hi guys,

Started the car today and heard this inconsistent ticking like sound while the car was warming up. Please see the google drive link to the video below. It sounds like it's coming from somewhere near the alternator area. The serpentine & AC belt are relatively new (1.5 years old). The sound went away when I returned after about an hour's drive. Another point to note is that when the car is running the voltage is around 12.3-12.4V (not sure if this is in any way connected to the sound). I've read that it should be closer to 14V when the car is running. Battery is new, less than a year old & alternator about 3 years old. Does this sound like a pulley or tensioner on its way out? TIA!

Link to the video: https://drive.google.com/file/d/1SXG...ew?usp=sharing

[Arith2]

Sounds like you may need a new alternator. It should be closer to 14V and you should spin it with the belt off. I had an alternator that functioned until I took the belt off and found almost an inch of movement in the pulley. Something's screwed up and it's probably that alternator.

[FBloggs]

That is a bearing that has dried out on the idler pulley. Probably the one by the alternator but you should change them all . It is getting ready to spit ball bearings.
If you remove the accessory drive belt and then spin the pulleys by hand you'll feel how dry and loose they are.

[R1pilot]

Easiest way to find the source is to remove the belt and spin the pulleys.

When my alternator was on its way out, it was showing 12.x volts, but the battery light would occasionally light up as well. Does your battery light flicker?

[bigjae46]

If you're at 12v then the alternator is failed. Has a similar issue and it ended up being a failed regulator. Fixed it for about $90. If I had to do it again...I wouldn't even need to remove the alternator. Could be done in car.

Make sure you get the correct VALEO regulator. Even if you have a Bosch rebuild..its a Valeo regulator.

[sapote]

Hi guys,
Another point to note is that when the car is running the voltage is around 12.3-12.4V (not sure if this is in any way connected to the sound). I've read that it should be closer to 14V when the car is running. Battery is new, less than a year old & alternator about 3 years old.

3 years old remanufactured alternator?
Where did you measure the voltage? Try to measure directly on the nut holding the fat cable to the rear of the alternator to make sure if it's not a bad unit but having a bad cable connection elsewhere.

[speedster]

Sounds like you may need a new alternator. It should be closer to 14V and you should spin it with the belt off. I had an alternator that functioned until I took the belt off and found almost an inch of movement in the pulley. Something's screwed up and it's probably that alternator.

That is a bearing that has dried out on the idler pulley. Probably the one by the alternator but you should change them all . It is getting ready to spit ball bearings.
If you remove the accessory drive belt and then spin the pulleys by hand you'll feel how dry and loose they are.

Thanks for the suggestion! I'll remove the belt, spin them and check but probably a good time to change them all out at once. Not sure how hard of a DIY it is though.

Easiest way to find the source is to remove the belt and spin the pulleys.

When my alternator was on its way out, it was showing 12.x volts, but the battery light would occasionally light up as well. Does your battery light flicker?

My battery light does not flicker, it displays 12.x volts in the secret/hidden menu & on my radar detector. It's a 3 year old rebuilt alternator that I would have expected to last a longer time.

If you're at 12v then the alternator is failed. Has a similar issue and it ended up being a failed regulator. Fixed it for about $90. If I had to do it again...I wouldn't even need to remove the alternator. Could be done in car.

Make sure you get the correct VALEO regulator. Even if you have a Bosch rebuild..its a Valeo regulator.

Thanks for the helpful suggestion regarding the regulator. How did you narrow it down to the regulator and not the alternator? Mine is a 3 year old Bosch rebuilt unit. Seem's like I should replace both the alternator & the regulator.

3 years old remanufactured alternator?
Where did you measure the voltage? Try to measure directly on the nut holding the fat cable to the rear of the alternator to make sure if it's not a bad unit but having a bad cable connection elsewhere.

Yup its a 3 year old Bosch remanufactured alternator. I measured the voltage while the car was running through the secret/hidden menu as well as on my radar detector. It's always 12.x volts while idling. I'll measure the voltage on the nut at the rear of the alternator. Thanks for the suggestion!

[sapote]

I'll measure the voltage on the nut at the rear of the alternator. Thanks for the suggestion!

If it's a plastic nut then swap out with a metal one, if the cable has no exposed conductor. 12.3V with hidden display is too low even the hidden display normally shows about 0.4v lower.

[WestBankM4]

Sounds like the exact same problem I'm having, except mine is a bit worse.

I've narrowed it down by listening to each part in the area with a screwdriver, and this was the problem for me. Listening to yours, it's definitely your idler pulley but I could be wrong. RealOEM shows the part number as, #11287841228.

[speedster]

Sounds like the exact same problem I'm having, except mine is a bit worse.

I've narrowed it down by listening to each part in the area with a screwdriver, and this was the problem for me. Listening to yours, it's definitely your idler pulley but I could be wrong. RealOEM shows the part number as, #11287841228.

Thank you. I too listened with an engine stethoscope and seems like the idler pulley. Just got all the pulley's, belts and tensioners today; will plan on doing the whole job sometime soon. Also got a new (remanufactured) alternator. Seems like the current one only lasted 2 years.

[WestBankM4]

Thank you. I too listened with an engine stethoscope and seems like the idler pulley. Just got all the pulley's, belts and tensioners today; will plan on doing the whole job sometime soon. Also got a new (remanufactured) alternator. Seems like the current one only lasted 2 years.

I had new belts placed last month, rest of the cooling system has been previously overhauled in the last year, so I think I'm good. My idler pulley is inbound from ECS, should be here today I believe, went the OEM route.

[speedster]

Just wanted to update this thread: I changed all accessory pulleys, belts and tensioners. Also replaced the alternator (& voltage regulator). The sound has gone and the voltage is back where it should be, about 13.4V while idling. The old pulleys were definitely on their way out as they made the same sound when I spun them once removed. Thanks to all for your help.
The only issue I'm facing now is that, I cleaned the maf when I did the pulleys etc and the first time I started the car after the pulley job it started but was struggling and felt like it was almost going to die. After about 30 seconds it started idling like normal. Then I got a check engine light after driving for a bit and the code was "running too rich". Cleared it and it came back after a couple miles again. Car was running fine though. I cleaned the maf again thoroughly and let it dry for an hour, drove the car and this time I got a code for "running too lean". Car runs fine again. I'm thinking that somehow by cleaning the maf it has got spoilt? It seems very strange. Looks like I'll have to order a new one soon.


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[sapote]

[QUOTE=speedster;n94095]The old pulleys were definitely on their way out as they made the same sound when I spun them once removed.

..... and the code was "running too rich"./QUOTE]

Pulleys by themselves do not making noise unless when manually spun by hand. Whatever the pulley was attached to is the source of the noise, i.e. water pump, power steering or alternator.

Either a bad MAF or bad connection casing the DME ran in open-loop mode (no air metering and just control fuel injectors by look-up-table data)

[speedster]

[QUOTE=sapote;n94220]

The old pulleys were definitely on their way out as they made the same sound when I spun them once removed.

..... and the code was "running too rich"./QUOTE]

Pulleys by themselves do not making noise unless when manually spun by hand. Whatever the pulley was attached to is the source of the noise, i.e. water pump, power steering or alternator.

Either a bad MAF or bad connection casing the DME ran in open-loop mode (no air metering and just control fuel injectors by look-up-table data)

Thanks for the correction regarding the exact source of the sound. Regarding the codes running too rich & too lean, what do you suggest I do? Is replacing the MAF the first step? Not sure what you mean by bad connection casing the DME? I didn't touch the DME during the pulley/alternator/tensioner job so I doubt I would have affected any connections in there.

[sapote]

[QUOTE=speedster;n95676]

Thanks for the correction regarding the exact source of the sound. Regarding the codes running too rich & too lean, what do you suggest I do? Is replacing the MAF the first step? Not sure what you mean by bad connection casing the DME? I didn't touch the DME during the pulley/alternator/tensioner job so I doubt I would have affected any connections in there.

Meant to write "causing" but the autocorrect changed it to "casing". How did you clean the MAF? Hope it wasn't damaged during cleaning. Also check the pins if any got bent during installation. A bad connection causing the DME to run in opened-loop and rich fuel.