CX-9 2010 Engine noise (slow chattering or rattling)

nfn2000

Member
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2010 CX-9
Car has 144K miles. Only work that has been done includes:
1. Fuel injectors and spark plugs replaced
I have tried to capture the noise in this video. Noise is there even with AC off.
What could it be? No error codes. Engine oil looks fine although the engine does consume about a quart of oil every 2 months.
I suspect that some pully bearing or water pump issue?
Hard to hear when engine is cold. But can hear it 1 min after engine starts.
There is a slight oil leak from the power steering system. But turning the steering does not change anything about the noise.
 
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18 Mazda CX5 AW
When's the last time you replaced your belts? Any other problems , overheating, higher temps, low coolant levels, etc that you feel it could be a failing water pump?
 

nfn2000

Member
:
2010 CX-9
When's the last time you replaced your belts? Any other problems , overheating, higher temps, low coolant levels, etc that you feel it could be a failing water pump?
Belts have never been replaced. They look ok. No screeching noises. Temperature is perfectly normal. Heater heats fine. I have had to add 1 fourth of a quart of coolant every year (past 2 years). I was just mentioning water pump because I thought maybe the little metallic fan thing in the water pump was rattling somehow because the noise sounds metallic.
What is an idler pulley? Saw some videos on youtube about the noise that comes when pulley bearings go bad. Does this sound like that?
 
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18 Mazda CX5 AW
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Belts have never been replaced. They look ok. No screeching noises. Temperature is perfectly normal. Heater heats fine. I have had to add 1 fourth of a quart of coolant every year (past 2 years). I was just mentioning water pump because I thought maybe the little metallic fan thing in the water pump was rattling somehow because the noise sounds metallic.
What is an idler pulley? Saw some videos on youtube about the noise that comes when pulley bearings go bad. Does this sound like that?
Idler tales up slack and keeps everything tight and everything else running.

It's possible it could be the pulley bearings or maybe the water pump (I've never had a pump sound that bad) or something else. But you should probably at least have a mechanic take a look. You probably should also change the belts while your at it.

Maybe others can offer more expertise. You mentioned no error codes. You have no other engine problems? Loss of power? Engine or exhaust smoke?
 
Does not sound like a valve lifter.

Sounds like something that's rotating w/ a sloppy bearing. Hopefully an accessory like alternator or water pump.

Does it make the same sound when you idle in gear?
 

nfn2000

Member
:
2010 CX-9
Does not sound like a valve lifter.

Sounds like something that's rotating w/ a sloppy bearing. Hopefully an accessory like alternator or water pump.

Does it make the same sound when you idle in gear?
Yes the sound is same while in gear. Harder to hear if I rev up the engine.
No loss of power. No visible smoke or any unusual smell (ok maybe it smells like a typical 140K mile ford engine).
I also feel that its some kind of failing wobbly bearing.
 
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2014 Ford Explorer Sport, 2009 CX9(Wife's)
Try pulling the serpentine belt and running it again to see if noise disappears.
You should be able to run it for a minute or 2 without worrying about the battery dying.
 

nfn2000

Member
:
2010 CX-9
Took it to the dealership which as expected turned out to be a stealership. The dude says I need a new engine. See at 1:52 of this video he sent me:
The oil is not frothy so I dont think the coolant has made its way into the engine yet.
Will a water pump replacement help? How much does that usually cost? There is no oil in the coolant either.
Or is the dealership just bs-ing?
 
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18 Mazda CX5 AW
Took it to the dealership which as expected turned out to be a stealership. The dude says I need a new engine. See at 1:52 of this video he sent me:
The oil is not frothy so I dont think the coolant has made its way into the engine yet.
Will a water pump replacement help? How much does that usually cost? There is no oil in the coolant either.
Or is the dealership just bs-ing?
EDIT: reread your posts and listened to video and added comments[/EDIT]

Go to an independent local garage mechanic and get a diagnosis.
Before you took it in, was your coolant low? Have you had to keep refilling coolant over the past year?
EDIT: never mind. Reread your previous post... I've never seen coolant sold by the quart. Do you mean you used 1/4 of a gallon container per year? If so, that's slot to be adding. It's possible the engine might be damaged if it's been leaking coolant into the engine that long. Was the oil ever think or milkshaky?
You've been burning oil? How much oil have you had to add over past several months?

How long has the current oil been in the engine?
Hopefully a few months at least.
At this point, you really need to drain the oil and send a sample to Blackstone for analysis. See how much had been mixing with the oil.

Take to local mechanic for diagnosis, change oil , send oil sample in for UOA analysis.

If you need engine look at salvage engines, then new, then reman. Pick you poison.

EDIT: watched video. He didn't do compression test. No milky oil per the video. Have you notice any blue or white smoke out tailpipe. Does the engine stall or sputter? Plus you haven't thrown any codes? I think you need a second opinion just for peace of mind. It's 50/50 whether the engines bad. You do have the water pump leak, noises, etc. But no codes, no frothy oil, no sputtering, no overheating, no loss of engine power? Yeah 50/50. Get second opinion.

Also, if you need a new water pump and also need new engine gaskets/seals plus borderline engine problems, then replacement might be the way to go, if your keeping the car. At that many miles/years, I'd just throw a salvage engine in it.

Also, it's a 13 year old car... Get a cheap salvage engine( under $1000 ?) if you can find one and pay a local $600 to swap it out for ya.
 
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nfn2000

Member
:
2010 CX-9
EDIT: reread your posts and listened to video and added comments[/EDIT]

Go to an independent local garage mechanic and get a diagnosis.
Before you took it in, was your coolant low? Have you had to keep refilling coolant over the past year?
Yes coolant was low and was at the min line. But that has been happening slowly for the past 3 years.
EDIT: never mind. Reread your previous post... I've never seen coolant sold by the quart. Do you mean you used 1/4 of a gallon container per year? If so, that's slot to be adding. It's possible the engine might be damaged if it's been leaking coolant into the engine that long. Was the oil ever think or milkshaky?
Oil has NEVER been frothy. The coolant in the reservoir goes from max line to min line once every 1.5 years. It has been doing that for the past 3 years. So I basically have filled coolant from min line to max line 2 times in the past 3 years. I dont see any floating oil in the coolant reservoir either. I do some particles in the coolant tank though. I will try to fish those out to see that they are.
You've been burning oil? How much oil have you had to add over past several months?
I quart every 2.5 months (about 2000 miles). I have been changing oil every 6 months or so. I just changed the oil last week. The oil you see in the video is new. I might do the analysis thing with the drained oil from the last change since I still have it.
How long has the current oil been in the engine?
Hopefully a few months at least.
At this point, you really need to drain the oil and send a sample to Blackstone for analysis. See how much had been mixing with the oil.

Take to local mechanic for diagnosis, change oil , send oil sample in for UOA analysis.
Yes thats the next step.

If you need engine look at salvage engines, then new, then reman. Pick you poison.

EDIT: watched video. He didn't do compression test. No milky oil per the video. Have you notice any blue or white smoke out tailpipe. Does the engine stall or sputter? Plus you haven't thrown any codes? I think you need a second opinion just for peace of mind. It's 50/50 whether the engines bad. You do have the water pump leak, noises, etc. But no codes, no frothy oil, no sputtering, no overheating, no loss of engine power? Yeah 50/50. Get second opinion.
Engine is super smooth. No overheating. No bad smoke. Theres one code for traction control but that does not even light up the chk engine light.
Also, if you need a new water pump and also need new engine gaskets/seals plus borderline engine problems, then replacement might be the way to go, if your keeping the car. At that many miles/years, I'd just throw a salvage engine in it.

Also, it's a 13 year old car... Get a cheap salvage engine( under $1000 ?) if you can find one and pay a local $600 to swap it out for ya.
Edit: The guy said that the crankshaft is wobbly. Is that even a thing? Does that happen without engine shaking? Isnt the crankshaft basically that moves the car? I looked at the belt and it seemed to be moving straight. I will try to make a video of the moving belt from under the car.

I really dont wanna buy a new car in this crazy market.
 
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18 Mazda CX5 AW
Yes coolant was low and was at the min line. But that has been happening slowly for the past 3 years.

Oil has NEVER been frothy. The coolant in the reservoir goes from max line to min line once every 1.5 years. It has been doing that for the past 3 years. So I basically have filled coolant from min line to max line 2 times in the past 3 years. I dont see any floating oil in the coolant reservoir either. I do some particles in the coolant tank though. I will try to fish those out to see that they are.

I quart every 2.5 months (about 2000 miles). I have been changing oil every 6 months or so. I just changed the oil last week. The oil you see in the video is new. I might do the analysis thing with the drained oil from the last change since I still have it.

Yes thats the next step.


Engine is super smooth. No overheating. No bad smoke. Theres one code for traction control but that does not even light up the chk engine light.

Edit: The guy said that the crankshaft is wobbly. Is that even a thing? Does that happen without engine shaking? Isnt the crankshaft basically that moves the car? I looked at the belt and it seemed to be moving straight. I will try to make a video of the moving belt from under the car.

I really dont wanna buy a new car in this crazy market.
Even if local mechanic says it needs a new engine. You could always get water pump fixed.... Keep adding/changing oil and run the engine til it blows up/seizes.
The decide whether to get a salvage engine or a newer used car.
 

nfn2000

Member
:
2010 CX-9
Update: I was wrong about no oil in the coolant reservoir. It just seemed clear. I put in a rag inside and touched the coolant. Its definitely oily. So it seems that coolant and oil has mixed although not a lot to cause engine oil frothing. I do use synthetic oil and I heard that synthetic does not froth as easily.
The pulley coming out of the engine does seem a tiny bit wobbly after i took a slow-mo video of it using my phone.
Given that there are no codes, and no engine degradation yet, is it still possible to save the engine by get the water pump etc changed?
 
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18 Mazda CX5 AW
Update: I was wrong about no oil in the coolant reservoir. It just seemed clear. I put in a rag inside and touched the coolant. Its definitely oily. So it seems that coolant and oil has mixed although not a lot to cause engine oil frothing. I do use synthetic oil and I heard that synthetic does not froth as easily.
The pulley coming out of the engine does seem a tiny bit wobbly after i took a slow-mo video of it using my phone.
Given that there are no codes, and no engine degradation yet, is it still possible to save the engine by get the water pump etc changed?
EDIT: Get your local garage to look at it and ask them about just replacing water pump, changing oil and coolant and ask them if you can run the engine til it dies. That's what I'd do. If it's at the point it's beyond repair, might as well run it. Plus the noise might go away once water pumps replaced, belts changed and pulleys tightened. Save up for an engine in the meantime. Plus maybe stay in the right lane while driving in case your engine goes kaput, so you can coast off the road. You mentioned it's accelerating fine but if it gets to the point you're noticing loss of power and acceleration, and it's making noise then it's probably time to replace it...before it fails on the road. You really need a mechanics opinion after he/she looks at it.
 
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nfn2000

Member
:
2010 CX-9
Update: I seemed to have made a mistake in saying that there was oil in the coolant. I thought that the coolant felt slick and oily. I actually tried feeling the coolant from a new coolant bottle and it also felt oily. I guess I never played with coolant before!
So bottom line is that there doesnt seem to be any oil in the coolant. I pulled some coolant out of the reservoir and while it did look darker than usual but it does not have any oil layer on top.

Will talk to some shops tomorrow.
 
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2010 CX-9 GT
The water pump can leak in two ways, one is annoying and the other is potentially catastrophic. You appear to have the annoying coolant leak, where coolant comes out a weep hole and drips outside the engine. If you search for "ford 3.5 v6 weep hole" you will find descriptions of this. It is a pain to see but if you get a flashlight and maybe a borescope you can confirm this is what is happening. Replacing the water pump will help with this.

The catastrophic water pump failure mode results in the coolant ending up inside the timing cover of the engine, where it then drains into the oil pan, contaminating the oil and potentially destroying the bearings, VVT actuators, and perhaps the entire engine if it isn't caught and addressed quickly.

In either case, the oil rarely ends up in the coolant as there is no pressure on the oil inside the timing cover, so there's no force driving the oil into the cooling system. It's not a surprise that you didn't find oil in the coolant.

Replacing the water pump on this engine at a garage is a ~$2k or more job. To get to the water pump, the timing cover must be removed, which involves removing a lot of pieces (including the crank pulley). You can do it yourself for far less but it is a very involved job.

The oil leaking at the crank pulley is more concerning than the coolant leak at this point. It could be that the crankshaft seal has simply worn out, but that also could be caused by something more serious like a bad crankshaft bearing.

I'd recommend an oil analysis to see if there's any coolant or excess metal in the oil. If the oil is found to be contaminated, I'd call this motor toast. Beyond that, I'd take it to a mechanic you trust (not a dealer) and see what they find.

This is a crappy situation no matter what you do. Just fixing the pump is at least $2k and you still may end up with an engine that eats a bearing shortly after. Unfortunately, remanufactured and used motors for these are not plentiful or cheap. Used motors appear to start at around $2300 eBay and go up from there. By the time you pay someone to replace the water pump on the used motor and swap it in you are going to be over $3k. The trade in market has recently taken a bath and if you traded it in (in working condition) you might get $4-5k. If I were in your shoes, I would probably take it to CarMax (or some similar outfit) and get an offer. If it was anywhere near $4k I'd take the money and run.
 

nfn2000

Member
:
2010 CX-9
The water pump can leak in two ways, one is annoying and the other is potentially catastrophic. You appear to have the annoying coolant leak, where coolant comes out a weep hole and drips outside the engine. If you search for "ford 3.5 v6 weep hole" you will find descriptions of this. It is a pain to see but if you get a flashlight and maybe a borescope you can confirm this is what is happening. Replacing the water pump will help with this.

The catastrophic water pump failure mode results in the coolant ending up inside the timing cover of the engine, where it then drains into the oil pan, contaminating the oil and potentially destroying the bearings, VVT actuators, and perhaps the entire engine if it isn't caught and addressed quickly.

In either case, the oil rarely ends up in the coolant as there is no pressure on the oil inside the timing cover, so there's no force driving the oil into the cooling system. It's not a surprise that you didn't find oil in the coolant.

Replacing the water pump on this engine at a garage is a ~$2k or more job. To get to the water pump, the timing cover must be removed, which involves removing a lot of pieces (including the crank pulley). You can do it yourself for far less but it is a very involved job.

The oil leaking at the crank pulley is more concerning than the coolant leak at this point. It could be that the crankshaft seal has simply worn out, but that also could be caused by something more serious like a bad crankshaft bearing.

I'd recommend an oil analysis to see if there's any coolant or excess metal in the oil. If the oil is found to be contaminated, I'd call this motor toast. Beyond that, I'd take it to a mechanic you trust (not a dealer) and see what they find.

This is a crappy situation no matter what you do. Just fixing the pump is at least $2k and you still may end up with an engine that eats a bearing shortly after. Unfortunately, remanufactured and used motors for these are not plentiful or cheap. Used motors appear to start at around $2300 eBay and go up from there. By the time you pay someone to replace the water pump on the used motor and swap it in you are going to be over $3k. The trade in market has recently taken a bath and if you traded it in (in working condition) you might get $4-5k. If I were in your shoes, I would probably take it to CarMax (or some similar outfit) and get an offer. If it was anywhere near $4k I'd take the money and run.
Oh my! Could carmax be this dumb?!
Thanks for the info on the weephole. I have seen the repair video on youtube and that showed the weephole. Your explanation makes sense.
 
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2010 CX-9 GT
Oh my! Could carmax be this dumb?!
Thanks for the info on the weephole. I have seen the repair video on youtube and that showed the weephole. Your explanation makes sense.

I'm not suggesting being dishonest, just go to CarMax and ask for a trade in value and see what they offer.

They may take it, even with the noise. They can get things fixed cheaper than you and I can. Or,they will sell it to an auction house, someone else will buy it and will then part it out. There's some amount of salvage value they can recover even if the motor is hosed.
 
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Mazda CX-9 Grand Touring 2016
Don't talk about the oil foaming. That would require a very large amount of coolant in it. Way before you see foam you will see some degree of a milky appearance. That is too much coolant in the oil. Change the oil immediately, top off the coolant, clean off any dried coolant spots under the engine, and drive directly to a dealer to buy a different car.

An oil analysis will tell if there is coolant in the oil, and it'll list the wear metals from bearings or other parts that are normal or excessive in the oil. If the analysis is good, consider repairing and keeping the car. Otherwise trade it in on something healthier.
https://www.blackstone-labs.com/tests/standard-analysis/