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Discussion Starter #1 (Edited)
First off, clutches can have two sensors on the pedal. Our 2105 2.0 Mazda3 has a clutch position sensor that will cut off the cruise control when you barely push in on it. Our car has 3k miles.

My problem is the clutch position sensor is actually controlling the throttle by wire system in first and second gear.

Scenario:
1st gear, clutch fully out, going from idle to slow acceleration, barely push in on the clutch pedal = car accelerates and your head bobs back.

Same scenario: release remaining clutch pedal travel = car decelerates and head bobs forward.

Second gear does this some too, but I haven't been able to replicate it consistently. All the above observations only happen at low RPMs (traffic nightmare!).

I can do this over and over again in first gear and the actual clutch disk never disengages or slips, so I am 100% sure it is electronic related.

Shifting from 2nd onwards is buttery smooth and rewarding.

Any thoughts? 0:)
 

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More free time than money
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First off, clutches can have two sensors on the pedal. Our 2105 2.0 Mazda3 has a clutch position sensor that will cut off the cruise control when you barely push in on it. Our car has 3k miles.

My problem is the clutch position sensor is actually controlling the throttle by wire system in first and second gear.

Scenario:
1st gear, clutch fully out, going from idle to slow acceleration, barely push in on the clutch pedal = car accelerates and your head bobs back.

Same scenario: release remaining clutch pedal travel = car decelerates and head bobs forward.

Second gear does this some too, but I haven't been able to replicate it consistently. All the above observations only happen at low RPMs (traffic nightmare!).

I can do this over and over again in first gear and the actual clutch disk never disengages or slips, so I am 100% sure it is electronic related.

Shifting from 2nd onwards is buttery smooth and rewarding.

Any thoughts? 0:)
The car is giving itself gas when you have the clutch in so that it is easier to drive. Idle is ~550rpm but when you put the clutch in it revs to ~700. However, I am not having any problems with that.
 

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I feel like most of the clutch problems aren't clutch problems at all. They're the motor moving around because of the super soft engine mount this car has.
 

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I'm experiencing the same thing and I suspect its the soft engine mount too that's causing some sort of resonance.

The reason I don't think its the clutch is, if I just put the car in first, no throttle and fully clutch out, the car bobs my head too, nightmare in traffic.
 

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Are you able to shift smoothly from 1st to 2nd in slow-average acceleration conditions (a/c on or off)?
I can 50% of the time, just takes a little practice. Still doesnt do it half the time.

I feel like most of the clutch problems aren't clutch problems at all. They're the motor moving around because of the super soft engine mount this car has.
Yes.
 

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Discussion Starter #8
I've got an appointment with Mazda service tomorrow. Trying to decide if this will be an act of futility. I'm a 15 year manual transmission veteran and retired mechanic. The only reason to buy a manual is for fun (and perhaps longer service life), but I'm currently not having much fun driving this one.
 

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I feel like most of the clutch problems aren't clutch problems at all. They're the motor moving around because of the super soft engine mount this car has.
I'm experiencing the same thing and I suspect its the soft engine mount too that's causing some sort of resonance.

The reason I don't think its the clutch is, if I just put the car in first, no throttle and fully clutch out, the car bobs my head too, nightmare in traffic.
I can 50% of the time, just takes a little practice. Still doesnt do it half the time.



Yes.
I've got an appointment with Mazda service tomorrow. Trying to decide if this will be an act of futility. I'm a 15 year manual transmission veteran and retired mechanic. The only reason to buy a manual is for fun (and perhaps longer service life), but I'm currently not having much fun driving this one.
I put on a 80A JBR motor mount a few nights ago and all my shifting problems are gone! 1-2 has none of that jerk and the rest of the gears are great. The only problem is that now it feels like I'm driving a rally car and my interior vibrates like nothing else.
 

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I put on a 80A JBR motor mount a few nights ago and all my shifting problems are gone! 1-2 has none of that jerk and the rest of the gears are great. The only problem is that now it feels like I'm driving a rally car and my interior vibrates like nothing else.
Any comment about the CS Mount? I would love to get rid of that 1-2 gear jerk.
 

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Discussion Starter #11
Interesting that the CS mount solved your problem. Keep us posted.
I had a Mazda tech ride with me this morning and he didn't think there was anything he could do about the issue. I asked about TBW learning and if there were any service bulletins out on an ecu reflash. We determined unplugging the battery and having the car relearn me and my wife's driving style might be a good experiment. If that fails then I will look into shimming, removing, or modifying the clutch position sensor signal.
 

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I put on a 80A JBR motor mount a few nights ago and all my shifting problems are gone! 1-2 has none of that jerk and the rest of the gears are great. The only problem is that now it feels like I'm driving a rally car and my interior vibrates like nothing else.
Is that a transmission motor mount you’re talking about ? It’s 2020, I have a ‘17 Mazda3 bothered with the same issue. How’s it holding up?
 

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Rear motor mount and transmission mount from CS. Great combo.
CK
 

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I put on a 80A JBR motor mount a few nights ago and all my shifting problems are gone! 1-2 has none of that jerk and the rest of the gears are great. The only problem is that now it feels like I'm driving a rally car and my interior vibrates like nothing else.
I bumped up my idle rpm to 1080 and all vibrations are gone. Additionally, car picks up better
 
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