Help! Please! Odd Noise...grinding/churning?
 

Hi Everyone!

I have been a FREQUENT viewer of this forum but this will be my first post.
I currently drive the Alabaster White 2004 XFire Coupe. 50k miles --- been driving it since it had around 30k. A few months back, I began to heard a noise coming from under the hood, to me, it sort of sounds like a grinding/churning noise. I only notice it when I am either in a drive-thru or at a stop light.

The noise is very hard to explain but I think grinding/churning is fairly accurate; the churning almost has like a repetitive tick; as if maybe something is turning and again "grinding/churning"

I have taken it to Chrysler dealership twice and had the service mechanics looks at it. One who was a "Crossfire Specialist" ---- He found nothing at all wrong. While I understand..he is a professional...I know my car and I know when I originalyl bought it, it was not making this noise so I am PRETTY sure...that SOMETHING is going on; I just can't imagine what it is.

Have any of you heard this noise or would you have any clue at all as to what it could be? Any advice would be greatly appreciated.

I am at the point now where I am considering trading my car in for another Alabaster Coupe just to get rid of the noise but if I do that, I will lose financially --- so I would "prefer" not to.

Anyone?

Re: Help! Please! Odd Noise...grinding/churning?
 

Does the noise change with the heater/ air conditioner fan speed?

Re: Help! Please! Odd Noise...grinding/churning?
 

I don't think so. I feel like I hear it regardless. I don't think it's stronger when the heat nor the air is on.

Re: Help! Please! Odd Noise...grinding/churning?
 

Re: Help! Please! Odd Noise...grinding/churning?
 

The most common issue that causes a noise like this is the bearing going out in the idler pulley. Someone also has a similar noise coming from the alternator. If the car is in park/neutral do you hear the noise? If so does the sound change as you increse the RPM's?

Re: Help! Please! Odd Noise...grinding/churning?
 

Generally, I only hear it when I am stopped at a stop light or in a drive through. I notice that when I am in a drive-thru and put the car in park; as opposed to having my foot on the brake....I no longer hear the noise.

Re: Help! Please! Odd Noise...grinding/churning?
 

When the car is in park, I don't hear it. I realize that when I am at a red light or in a drive thru...my foot is generally on the break...that's when I hear it. When I put the car in park while sitting in a drive-thru --- the sound goes away.

Re: Help! Please! Odd Noise...grinding/churning?
 

When you're stopped does it sound like something turns on when you hear the noise?

Re: Help! Please! Odd Noise...grinding/churning?
 

No not at all. It may be an issue of me only hearing it because there is generally no outside noise at a stop light or while in a drive thru. Do you see what i'm saying? Maybe it makes the noise all along but I only hear it during those times.

Re: Help! Please! Odd Noise...grinding/churning?
 

Figured it out!! :)

Yesterday, I took it to the dealership and suggested to them that it could be the idler pulley. The results...

They said I need a new idler pulley AND a new water pump. Idler pulley with part and install is $190; Water pump with part and install is $1100. ----:o

I wanted to ask you all should I only do the OEM parts or is a water pump from GMB or BOSCH fine to use? Just trying to figure it out because the OEM water pump is $700. I have found the GMB and BOSCH water pump for $100.

Thanks again you all for helping me out yesterday! I really appreciate it.

Re: Help! Please! Odd Noise...grinding/churning?
 

:D Glad you got it figured out! I would do the idler pully first, then if it still is churning do the water pump. Stealerships tent to bump the diagnosis up to line the pockets of said stealership. Your wallet will love you! :D

Re: Help! Please! Odd Noise...grinding/churning?
 

There's your answer!

Now get her fixed and don't be such a stranger!!!:p

Re: Help! Please! Odd Noise...grinding/churning?
 

;) Thanks Tighed1, I try to give good advice. Sometimes I get it wrong. I also try to keep repairs to the lowest $ value. A little research goes a looooong way, especially when it involves my dollars. ;)

Re: Help! Please! Odd Noise...grinding/churning?
 

I have seen the pulleys on eBay for $15 new, brand name but I forgot what.
The OEM water pump may be a Bosch anyway, I purchased a Bosch water pump for my na for < $100 total and that was shipped to Canada. The SRT water pump is much more at OEM prices, it has three outlets and the na only has two. It is more anyway but not the half as much again that the OEM ones are.
You may need only one of these parts, employees in dealerships have to pass tests for lying and most of them pass with 100% marks.

Re: Help! Please! Odd Noise...grinding/churning?
 

So are you saying that buying the Bosch one is okay? The dealership told me that I should purchase from them because if something happens to the aftermarket part, I would have to pay for installation all over again because they offer no warranty. Thoughts?

Re: Help! Please! Odd Noise...grinding/churning?
 

:) I have never met a water pump I could not replace... That said, you really should first replace that idler pully and then see if the noise goes away. Try the simple inexpensive fix first! :)

Re: Help! Please! Odd Noise...grinding/churning?
 

Yes, I am going to certainly do that first. Should the idler pulley be OEM or is it fine to use an aftermarket one?

Re: Help! Please! Odd Noise...grinding/churning?
 

:( No recommendation on that, someone here might have a better brand/advice on which part to use. I for sure would not use OEM because chrysler seems to add quite a premium on their parts. I found autozone/oreillys to have pretty good parts but again for the XF someone else might have to chime in. :(

Re: Help! Please! Odd Noise...grinding/churning?
 

You can use an after market Idler pulley with no issues..... I have a couple of Gates pulleys on my Aero and they work fine..... I too would change the pulley and see how the car is.... then I would find a new shop to work on my car..... I use a good indy MB shop.....;)

Re: Help! Please! Odd Noise...grinding/churning?
 

You can find out which part is at fault just by removing the serpentine belt and rotating the pulleys by hand, shake them around a little as well. See if there is any harshness in the rotation.

If the OEM pump is a Bosch it will have the Mercedes part number and the Bosch number stamped on it. If you buy the Bosch pump in a Bosch box it will have the Bosch number stamped on it.
You have to ask yourself if the Mercedes number is worth $600. I know what my answer is.

Find out what's wrong before you spend a penny.