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Discussion Starter · #1 ·
Not a click, not a clunk, but a single clack when accelerating from a stop. It sounds like the clack the EVSE makes when turning on. The interesting part is, it makes the sound most of the time, not all the time.

So far, I've check the brakes and wheel bearings and they're fine. The suspension doesn't make any noise going over speed bumps, expansion joints, etc.. Next, weather permitting, I'm going to take the bottom cover off and look around under there.

Any thoughts?
 

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Try to push "gas" with brakes applied. Shift to R and do the same. Still there?
will the clack appear in L when you push or let off?
 

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Discussion Starter · #9 ·
Try to push "gas" with brakes applied. Shift to R and do the same. Still there?
will the clack appear in L when you push or let off?
I couldn't find my 32mm socket, so a friend came over with his and we checked the axle nuts and they were fine. We tried the accelerator with the car "in gear" and foot on the brake and it produced no noise. I've also stopped the car in D, L and with the paddle, and 90-95% of the time the clack is still there when taking off.
When the weather stays better, I'm going to take the bottom cover off and stick something in there to isolate the sway bar, to see if there's any change in the noise.
 

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Not a click, not a clunk, but a single clack when accelerating from a stop. It sounds like the clack the EVSE makes when turning on. The interesting part is, it makes the sound most of the time, not all the time.

So far, I've check the brakes and wheel bearings and they're fine. The suspension doesn't make any noise going over speed bumps, expansion joints, etc.. Next, weather permitting, I'm going to take the bottom cover off and look around under there.

Any thoughts?
I went through four sets of motor mounts in my EV-1s. Electric motors are notoriously high-torqued. The symptom was a single "clunk!" at hard acceleration and swift deceleration.
 

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Could it be in item simply rolling around loose somewhere? Side door pockets, center console, glove box, etc.? If it's definitely from under the hood, maybe a rock or other item is loose and banging. Or something fell down into defroster vents and bangs around. There might be a slope that the item rolls up when you come to a stop and then when accelerating it rolls back and makes a clunk.
 

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Discussion Starter · #12 ·
I went through four sets of motor mounts in my EV-1s. Electric motors are notoriously high-torqued. The symptom was a single "clunk!" at hard acceleration and swift deceleration.
There's nothing like that going on, it's just a little clack, like a relay closing, and it only happens from a stop. Interestingly enough, there were a couple of stops where I didn't hear the clack.
 

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Discussion Starter · #13 ·
Could it be in item simply rolling around loose somewhere? Side door pockets, center console, glove box, etc.? If it's definitely from under the hood, maybe a rock or other item is loose and banging. Or something fell down into defroster vents and bangs around. There might be a slope that the item rolls up when you come to a stop and then when accelerating it rolls back and makes a clunk.
Not from under the hood, it sounds more like underneath, and only from a stop, no other time.
 

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Not from under the hood, it sounds more like underneath, and only from a stop, no other time.
Check for loose things everywhere, including under the seats. Coming from a lot of VW's, I'm used to having to track down odd rattles and clunks. It's amazing how sounds like that will bounce in the cabin and mislead you as to their location. I've had sounds that I could swear were coming from the driver's side and it wound up being on the passenger side. Maybe get a passenger to help track down the source location and go from there.

You say "only from a stop", but maybe try this. Come to a firm stop and then start out very slowly and after getting a little speed, hit the accelerator and see if you can get the clack. Then you can say whether it is from a stop related or acceleration at some point after stopping.
 

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Discussion Starter · #15 ·
Check for loose things everywhere, including under the seats. Coming from a lot of VW's, I'm used to having to track down odd rattles and clunks. It's amazing how sounds like that will bounce in the cabin and mislead you as to their location. I've had sounds that I could swear were coming from the driver's side and it wound up being on the passenger side. Maybe get a passenger to help track down the source location and go from there.

You say "only from a stop", but maybe try this. Come to a firm stop and then start out very slowly and after getting a little speed, hit the accelerator and see if you can get the clack. Then you can say whether it is from a stop related or acceleration at some point after stopping.
The sound is definitely outside, underneath the car. The sound is there if I stop the car by brake pedal or by one pedal driving and take off.
I tried your suggestion and this is what I got. If I accelerate from stop with D or L, I get the clack. Next, I put the car in D and let it creep forward first, then hit the pedal. Whether accelerating fast or slowly, I didn't hear the clack.
I'm going to experiment with this method a few times and see if the results are consistent.
 

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That is an odd one. Some other ideas;
Try it with windows down and head out window a little to verify it's more an external sound. Also, trying to notice if it's coming more from the front, rear, or below.
Push down brake pedal with left foot. Shift into reverse and hit the accelerator just a little. Then shift into drive, while holding brake, and hit accelerator a little again. Maybe motor movement could be a cause.
 

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Discussion Starter · #17 ·
That is an odd one. Some other ideas;
Try it with windows down and head out window a little to verify it's more an external sound. Also, trying to notice if it's coming more from the front, rear, or below.
Push down brake pedal with left foot. Shift into reverse and hit the accelerator just a little. Then shift into drive, while holding brake, and hit accelerator a little again. Maybe motor movement could be a cause.
I've checked the motor mounts previously and they're fine, no noises.
I had three chances to creep/accelerate on the way into work. The first time was a click, the second time, I didn't hear anything, the third was the clack.
 

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CV joints? I can hear mine in garage - especially in L.
 

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something loose in the car? I am running out of options.
 
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