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Discussion Starter #1 (Edited)
Show us your automotive diagnostic skills. Or more likely, let’s see who is just plain lucky! A squeak, creak, or rattle in your beloved vehicle can make you crazy in short order. I had two noises coming from the front of my 2003 M5 with 20,000 miles. Due to a recent accident involving a crack-smoking pickup truck driver plowing into my parked M5, my car was repaired (or rather, “restored") to the tune of approx. $22,000.

SOUND #1: So this first noise was a metallic, sheet-metal sound coming from what I thought was ahead of the steering wheel, engine side of the firewall. The sound could be easily reproduced by throwing the steering wheel side-to-side while traveling slowly in a parking lot. It would also clank when hitting some of the larger bumps in the road. Quite loud. Any ideas?

SOUND #2: This one was more of a “creak”. This would happen over bumps. It would also happen when moving slowly (as in 1st gear), when applying power and also deceleration. Since both struts and upper strut bearings were replaced, my first theory was a binding strut, or perhaps a spring perch, or misaligned strut or misaligned spring. Complete disassembly of the strut assembly showed no problems. Upon further experimentation, it would also do the same creak, albeit a shortened version, upon engine startup and also shutdown. The interesting thing is that I could bounce the car up and down violently while parked (by pulling/pushing on the body just behind the headlights with the hood open) and could NOT make it creak. I saw evidence of my Dinan strut brace imprinting into the new hood insulation, but removal of the Dinan piece made no difference in the creaking. Take a guess what I found!

Hint: Use ALL the clues. Don’t guess “bad struts” if the noise couldn’t be reproduced by bouncing the suspension while parked. Hint #2: I searched the Board for “front noise” and got 7 pages of results. None of these threads contained the correct diagnosis. Don’t feel bad if you get it wrong. It took me approx. six evenings with the car up on jacks to figure both of these out ( I'm slow but thorough!)


Have fun! Winner gets the M5Master Mechanic Diagnostician Magician Award (a.k.a. bragging rights).

cherrsagai
 

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Common problem. Bad steering control arms. They always need replacing, particularly on X5s. Various symptoms. All of yours fit the symptoms.
 

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No guesses and I don't mean to hijack the thread but I had a dandy in a Mitsu 3000GT. A popping noise everytime I let out the clutch from a stop. It turned out to be a piece of plastic popping against the frame when the engine rocked during clutch engagement. It took a master tech 4 hours to find it. I have a noise in my M5 I need to start another thread about.
 

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Discussion Starter #5
Guys - Don't feel bad, the dealer couldn't figure it out either.

Digi: Not the control arms, that would be too easy! Besides, the control arm (wishbone), traction strut, tie rod end, steering box, and pitmann arm were all replaced on the left side.

Richard in NC: You're getting close on NOISE #2! Take a stab!

PhillyM5: Cmon, take a WAG. Hint: Your silver car had this area (part) replaced with aftermarket. OK, so did your blue car.
 

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ELEVENS said:
SOUND #2: This one was more of a “creak”. This would happen over bumps. It would also happen when moving slowly (as in 1st gear), when applying power and also deceleration. Since both struts and upper strut bearings were replaced, my first theory was a binding strut, or perhaps a spring perch, or misaligned strut or misaligned spring. Complete disassembly of the strut assembly showed no problems. Upon further experimentation, it would also do the same creak, albeit a shortened version, upon engine startup and also shutdown. The interesting thing is that I could bounce the car up and down violently while parked (by pulling/pushing on the body just behind the headlights with the hood open) and could NOT make it creak. I saw evidence of my Dinan strut brace imprinting into the new hood insulation, but removal of the Dinan piece made no difference in the creaking. Take a guess what I found!


Have fun! Winner gets the M5Master Mechanic Diagnostician Magician Award (a.k.a. bragging rights).

cherrsagai
This sounds like something having to do with the clutch.. possibly the throwout bearing? I used to get the squeak when I would just let the car go over speed bumps without hitting the clutch, but it seems to have gone away now that I hit the clutch every time I go over one.
 

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my M5 made noise #1 after getting headers installed. There was a heat shield that was bent and contacting one of the tie rods. I bent it back, problem solved.
Mike
 

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#1 could it be sway bar bracket in the rear.....you thought was clanking in the front.

#2 something to do with the brake lines?
 

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sound one - do you use a bunch of keys with the igntion key on it? I have had a simialrly confusing noise, and realised my house keys were hitting on the steering cowling.

number 2 I dont know.....



Stu
 

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Discussion Starter #10 (Edited)
mottati said:
my M5 made noise #1 after getting headers installed. There was a heat shield that was bent and contacting one of the tie rods. I bent it back, problem solved.
Mike
Close enough! WE HAVE A WINNER!!!! :happybirt The stock headers were hitting the heat shield, plus the hanger/clamp just behind the header was hitting the underbody. I bent the heatshield back just like you did, but on the clamp I cut off 3/16" or so using a cutoff wheel.

Now, what about sound#2? Hint1: "Richard in NC" was close when he mentioned the engine rocking... ;) Hint2: I've never heard this (culprit) part mentioned on this board...
 

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ELEVENS said:
Close enough! WE HAVE A WINNER!!!! :happybirt The stock headers were hitting the heat shield, plus the hanger/clamp just behind the header was hitting the underbody. I bent the heatshield back just like you did, but on the clamp I cut off 3/16" or so using a cutoff wheel.

Now, what about sound#2? Hint1: "Richard in NC" was close when he mentioned the engine rocking... ;) Hint2: I've never heard this (culprit) part mentioned on this board...

I'd guess motor mount, based on the hint. Engine hitting the dinan bar (there's not much clearance anyway), which is rubbing on the underside of the hood...
Mike
 

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Discussion Starter #12
mottati said:
I'd guess motor mount, based on the hint. Engine hitting the dinan bar (there's not much clearance anyway), which is rubbing on the underside of the hood...
Mike
BINGO!!! :happybirt :happybirt

MOTOR MOUNT was the problem. When under the car, I was using a pry bar on the various parts and low and behold - when I pried up the engine on the passenger size, there was the creak! The 16mm nut on the top of the motor mount was very loose. So I tightened it up (about 1 full turn), then checked the other side. That one was not quite as loose, but still turned a 1/4 rotation. Checked it with the pry bar after tightening, no noise! Test drive - noise gone! So if you have a creak that happens under light throttle and throttle lift, inspect your motor mounts!

Good one, Mottati. :cheers:

:flag:
 

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Discussion Starter #13
Update: Apparently the final chapter hasn't been written. The creak is back. So I popped the hood and shined a flashlight down the right (passenger) side of the motor focusing the light onto the top of the motor mount. Guess what - It's broken! The aluminum webbing on the piece that attaches to the engine is busted. New parts are being over-nighted.

It's interesting that both the SA and master tech drove the car, and could not figure this out. But then, it took me probably a half-dozen attempts.

Here's a pic of the motor mount looking down between the left fender and the engine. You can see the broken tab under the nut. No wonder that nut was so loose - 1/2 of the contact surface has moved away. Also, no wonder the exhaust headers were hitting the other side of the car. The engine has shifted about 1/4" to the left.
 

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it's still disappointing when a master tech cant make a diagnosis of a mechanical problem. I had my car in last week for this "clunk" noise on bumpy roads, speed bumps, driveways etc. They said aftermarket suspension, probably a bad strut, but thrust arm bushings are bad. I said to replace the bushings, and pointed out that the car had been in twice for this same sounding noise. Previous visits, they tightened misc bolts in the front end which fixed it, for 6 mos at least. Car goes to dinan on monday so we'll see.
Most dealer techs do not seem to be good diagnosticians, in my experience, which is too bad. I often get the feeling that i know more then the people i'm dealing with, or at least i care more!
Mike

ps, elevens, my car creaks occasionally too, going into driveways, dinan strut bar rubbing on the underhood pad.
 

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ELEVENS said:
Update: Apparently the final chapter hasn't been written. The creak is back. So I popped the hood and shined a flashlight down the right (passenger) side of the motor focusing the light onto the top of the motor mount. Guess what - It's broken! The aluminum webbing on the piece that attaches to the engine is busted. New parts are being over-nighted.

It's interesting that both the SA and master tech drove the car, and could not figure this out. But then, it took me probably a half-dozen attempts.

Here's a pic of the motor mount looking down between the left fender and the engine. You can see the broken tab under the nut. No wonder that nut was so loose - 1/2 of the contact surface has moved away. Also, no wonder the exhaust headers were hitting the other side of the car. The engine has shifted about 1/4" to the left.
Can't tell if they are stock, but you might want after market, some of the SSK companies have motor mounts too. They should be more robust.
Regards,
Jerry
 
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