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Grinding noise when turning left and hard acceleration

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Location
Bedford
#1
I don't do this real often, but sometimes I just need to get on the gas while turning left so I can get into the small gap in traffic. Get a bit of wheel spin and I get a terrible grinding noise that sounds like it's coming from front right of car during wheel spin. I first noticed this on Friday July 9th. I checked for wheel bearing play and as far as I can tell there's none. I checked suspension stuff and am not seeing anything obviously wrong, no torn boots on anything. Steering and suspension still feels solid when driving. The other thing I noticed right about the same time is that the engine seems louder (but not significantly so), especially during a cold start. It could be placebo because I hear one sound and now I'm looking for others because I don't like abnormal noises coming from my vehicles. Haven't replaced anything that would make it louder. The trim in the interior plastic also vibrates more at first cold start and during driving which also started at the same time. I know correlation doesn't always equal causation and these don't really seem linked at all, but I wanted to put that in as something I have experienced. I'm not really worried about the trim vibrating, it's a nearly 6 year old economy car, so it's expected. I mention it because it wasn't doing it prior and suddenly I'm getting a louder noise from the engine and more trim vibration

I don't feel any vibrations or noise from the front right when driving normally. The grinding only happens on a hard left with acceleration. I tried it with sport mode as well and it has the same result. My first guess was wheel bearing or CV joint, but wheel bearing feels fine as I mentioned and I spun the wheel off the ground and didn't hear any noises from the CV joint. I've had bad wheel bearings in my other cars and know what they sound like which is a constant low whirring noise when the wheel is spinning that goes along with the speed of the wheel and I don't hear that in this case. I've never had a CV joint failing on any of my cars but from what I read it clicks constantly, and I don't hear any clicking. My other thought is an issue with the transmission, but not sure how to diagnose that. I did try a couple accelerations when turning right and couldn't make the noise, so it's only left turns on the right front corner of the car to the best of my hearing ability when inside the cabin. I checked for loose plastic near the wheel and didn't see any. The sound is more metallic from what I can hear, but I'm not 100% certain on that.

Recent work on the car: Passenger side motor mount (torqued down with a torque wrench, but I haven't checked and they could have backed out), coolant replacement, transmission fluid replacement with Ravenol MTF-2 75W-80, spark plugs. About a month after doing that work I drove the car on a 3000 mile road trip that was uneventful as far as car issues other than getting the engine temps a bit high driving up inclines in Utah and Colorado. As soon as I realized it both times I slowed down and turned on the heater to full blast to help cool it down. It's been a month since the trip. Engine oil was replaced right before and right after that trip. Haven't noticed any drips or leaks from anything.

I had read something of an issue that sounded similar that someone had and they said once their front brakes were replaced the issue was gone after having replaced the wheel bearing that didn't fix the issue. I still have life in my pads, but there's a good sized lip on the rotor from wear. Probably time to swap the brakes. I replaced them before somewhere around 3 years ago and ~45K miles and I now have 93K miles. I used the brakes a lot harder my first couple of years of ownership. I didn't realize how much they would wear and ran them down to nothing for my first set to the point that the lip of the rotor was rubbing on the metal back plate of the pad. It's not there yet, but I won't wait this time.

I suppose I could just do a brake replacement and test but I was just wondering what others may suggest. It only does this when accelerating and turning left from a stop when I get wheel spin. I've done hard left corning at speed and did some fun turns around some roundabouts without any grinding when driving it to test.
 


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Location
Indianapolis, IN, USA
#2
Disclaimer: I have no damn idea. But I'd check first the passenger side mount you replaced. Bolt could be broken or worked itself loose? Just a thought since that's the side it's coming from and that mount takes a lot of pressure when accelerating.
 


OP
S
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Location
Bedford
Thread Starter #3
I finally got a moment this evening to check the torque on all the passenger side motor mount bolts. The only one that needed a little tightening was the main bolt that goes in the middle of the mount, but it wasn't significant. It also didn't change the loud noise or vibration in any way.

I investigated a bit further and listened to the engine to try and pinpoint where the loudness is coming from. When I first cold start the car it goes to about 1200-1300 rpm as it normally would before settling down to 800-900ish at regular idle. During that 1200 rpm idle is when it's the loudest. It's normal at normal idle. When I rev it up I get the loudness when it goes through the 1200-1300 area (I didn't pay attention to the exact range, bit likely up to 2000), and then the loudness settles down and it's just engine revving. When the rpm comes back down it again hits that range again and vibrates and is louder until it goes down to idle and then it's fine.

I will have my roommate rev the engine for me tomorrow so I can actually check from outside the cabin, but as far as I can tell the loud sound is coming from behind the engine. It doesn't really sound like vibrating heat shields. But it does make the whole car vibrate which is why the interior trim is vibrating like crazy. Checked the engine oil and it's fine.

I ordered new brakes, just waiting for them to ship in. I don't know if that will solve the grinding noise. These two issues don't seem at all related from what I can tell.

Driving my truck for now in case this is a serious issue, don't really want to do more damage.
 


OP
S
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397
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Location
Bedford
Thread Starter #4
Replaced the front brakes but the grinding noise persists.
 


XR650R

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Eerie
#5
U joint on the right driveshaft?
 


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Location
Springfield
#6
My work vehicle makes an annoying clicking sound. It too is front-wheel drive, and the technician said the CV axle needs to be replaced. Maybe it's your CV axle making the noise.
 


OP
S
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Location
Bedford
Thread Starter #7
Maybe. I drove it to work today and it seems like it's getting worse. I could hear a rotational noise sometimes. I just dropped it off at the mechanic this evening. Seems like two separate issues and I'm just not skilled enough to diagnose them. I don't like wasting money throwing parts at it until it works again.
 


XR650R

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#8
I think Sprinkle Star nailed it. I guess we'll see.
 


OP
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Location
Bedford
Thread Starter #9
They looked at it some more after hearing the noise and couldn't figure it out. Said everything looks good. They point to the Cobb rear motor mount as the problem for the vibrations. But it's been on there since nearly new. The car was pretty much vibration-less when brand new with the stock mounts, and only added small amount of vibration after I installed it. Since then it's been fine, until suddenly there's a lot of vibration.

They said they've done all they can. They swapped out the transmission mount as it was the only original mount in the car still. It probably needed to be done anyway judging by how bad the passenger side mount was. So I'll pick it up and look at the Cobb mount to see if it looks damaged or something. Maybe swap in the original rear motor mount to test if I can find it in my storage unit. That wouldn't solve the grinding noise though, so I don't know.
 


OP
S
Messages
397
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Location
Bedford
Thread Starter #11
I thought about grabbing my dashcam footage and seeing if it captures the sound. If that doesn't work, when I have time I'll try to attach a camera somewhere outside and see if I can get it to do it. I plan to be going out of state this weekend and driving back with another car so I don't have to daily drive my truck anymore since this Fiesta is going to take awhile to figure out.
 


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Location
Canada
#12
I thought about grabbing my dashcam footage and seeing if it captures the sound. If that doesn't work, when I have time I'll try to attach a camera somewhere outside and see if I can get it to do it. I plan to be going out of state this weekend and driving back with another car so I don't have to daily drive my truck anymore since this Fiesta is going to take awhile to figure out.
I may have missed it in your other posts, but I'm also wondering whether the noise is present everywhere after certain steering wheel angle or only in a certain range and disappears if you keep cranking the wheel past it? How far is the wheel turned before it starts grinding?

Either way, you can probably note the wheel position and then raise the right wheel on jack stands, set the wheel angle, put the car in neutral and see if you can reproduce it by just spinning the wheel.
 




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