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Discussion Starter #1
I am really waiting for someone to "crack" the torque limiter, aside from using one of the piggybacks available ($$$). Especially if you could just flip a rocker switch to disable it when you wanted. Now that I am acclimated to the car, 1st and 2nd feel a bit too limited, underpowered. (4th gear is my favorite. :) )

Just thinking...is there not a simple sensor somewhere that tells the ECU what gear the car is in? Could we not just trick the computer into thinking the car is always in 4th? Other than the torque limiter, I can't think of anything else that would be affected by what gear the car is in. Also, I know the trans is very mechanically complex, but it shouldn't be too electronically complex (if at all); not like the new fancy automatics that are controlled by TCMs, etc; so a hack may be easy once someone figures it out.

Anyone know what sensor is responsible for triggering/signalling the torque limiter? (those with shop manuals?)

Excuse me if I am oversimplifying it.
 

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I was wondering about the same thing. I thought someone posted that there was a couple of switches on the tranny, that basically told the ecu what gear the car was in.. If the is in-deed the case then it should be pretty easy to make a switch box to trick the ecu into thinking it's in 4th or greater all the time, you could use a 2 pos. switch. Position "A" normal stock, position "B" full torque in all gears. I would be willing to make a prototype (and test it on my car) if someone can give me the schematic showing the switch and how it is wired into the ecu. I could put an led on it that would illuminate when in position "B" - this way you would know visually what mode it was in. Anybody got a shop manual ?
 

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I checked this out 2 months ago but was waiting for better weather to try it out. If you take the lower panel off and look at the transaxle you will see 2 switches mounted in the end of the housing (driver's side) one of them is the reverse light switch and the other is the 1st/Neutral/2nd gear switch. Right off the top of my head I think the upper one is the 1/N/2 switch, the switch is closed in the Neutral position and open in both 1st and 2nd gear. In other words the ecu only knows when the trans is in 1st or 2nd gear by loosing the signal from this switch, if you jump the wires (and you can put a switch on the dash to control this) you can fool the ECU into thinking the transaxle is NEVER in 1st or 2nd. Now that the ice and snow and most of the rain is gone I'm going to try this and see what happens.
 

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[quote author=Byron link=topic=70198.msg1225460#msg1225460 date=1172190975]
I checked this out 2 months ago but was waiting for better weather to try it out. If you take the lower panel off and look at the transaxle you will see 2 switches mounted in the end of the housing (driver's side) one of them is the reverse light switch and the other is the 1st/Neutral/2nd gear switch. Right off the top of my head I think the upper one is the 1/N/2 switch, the switch is closed in the Neutral position and open in both 1st and 2nd gear. In other words the ecu only knows when the trans is in 1st or 2nd gear by loosing the signal from this switch, if you jump the wires (and you can put a switch on the dash to control this) you can fool the ECU into thinking the transaxle is NEVER in 1st or 2nd. Now that the ice and snow and most of the rain is gone I'm going to try this and see what happens.
[/quote] Sweet deal man, let us know what happens.......... Can't wait to find out!!!! :D :D :D
 

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Subbing, drooling, and standing poised and ready with wire strippers and a soldering iron in hand!

While we're at it, does anybody know how to defeat the torque limiter that kicks in when the wheels are turned?
 

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I'm waiting for the factory service manual with wiring diagrams to show up, I went looking for the sensor for the steering angle input for the ECU but could not find it at the steering rack. I guess it is up under the dash or at the wheel, I did not have the time to tear it all apart looking for it. I am hoping it is just a potentiometer and we can just install a resister in the line to Lie to the ECU that the wheel is at center. Again I would think that you could put a switch in the system to turn it on and off.

<Mad scientist rubbing hands together with evil grin on face>
 

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[quote author=Byron link=topic=70198.msg1225554#msg1225554 date=1172194180]
I'm waiting for the factory service manual with wiring diagrams to show up, I went looking for the sensor for the steering angle input for the ECU but could not find it at the steering rack. I guess it is up under the dash or at the wheel, I did not have the time to tear it all apart looking for it. I am hoping it is just a potentiometer and we can just install a resister in the line to Lie to the ECU that the wheel is at center. Again I would think that you could put a switch in the system to turn it on and off.

<Mad scientist rubbing hands together with evil grin on face>
[/quote]

It's about time. I needed a new hero!
 

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[quote author=Byron link=topic=70198.msg1225554#msg1225554 date=1172194180]
I'm waiting for the factory service manual with wiring diagrams to show up, I went looking for the sensor for the steering angle input for the ECU but could not find it at the steering rack. I guess it is up under the dash or at the wheel, I did not have the time to tear it all apart looking for it. I am hoping it is just a potentiometer and we can just install a resister in the line to Lie to the ECU that the wheel is at center. Again I would think that you could put a switch in the system to turn it on and off.

<Mad scientist rubbing hands together with evil grin on face>
[/quote]
Most likely the steering angle sensor is also tied into other things such as the DSC. I wouldn't think about trying to defeat it.
 

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Discussion Starter #9
[quote author=Byron link=topic=70198.msg1225554#msg1225554 date=1172194180]
I'm waiting for the factory service manual with wiring diagrams to show up, I went looking for the sensor for the steering angle input for the ECU but could not find it at the steering rack. I guess it is up under the dash or at the wheel, I did not have the time to tear it all apart looking for it. I am hoping it is just a potentiometer and we can just install a resister in the line to Lie to the ECU that the wheel is at center. Again I would think that you could put a switch in the system to turn it on and off.

<Mad scientist rubbing hands together with evil grin on face>
[/quote]

HAHooooHAhahahHAHa!!! We are on the same page, my friend! :bananadance:

I'm glad I started this thread. Spark some conversation, anyways. I'd love to see the wiring schematic/sensor layout. Have you ordered it already?

If the sensors on the trans truely do what is supposed, it sounds like we might get there. My only concern is that the torque limiter would be tied to the vehicle speed sensor (RPM to gear ratios to gear(?); seems like the hard way to get there). Electro-Mechanical sensor seems easier, but I'm no expert.

I don't want to get too excited, but I am willing to experiment once I have some more knowledge...
 

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[quote author=GT1 link=topic=70198.msg1225598#msg1225598 date=1172194862]
I wouldn't think about trying to defeat it.
[/quote]

I've got a car with 263 horsies and I feel like I'm driving a Metro when I'm trying to make a quick right onto a busy road from a dead stop. That feature is on the top of my "stupidest things Mazda has ever done that deserve to face obliteration" list.

Besides, DSC is always off in my car anyway :p

Edit:

However, that is an excellent point. If you defeat this, DSC will more than likely become quite the safety hazard...It's hard to imagine exactly how it would react in emergency situations if it thinks the steering wheel is always at TDC. Perhaps the switch that defeats the angle sensor should also be set up to defeat DSC as well.
 

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[quote author=C-Bass link=topic=70198.msg1225957#msg1225957 date=1172199949]
[quote author=GT1 link=topic=70198.msg1225598#msg1225598 date=1172194862]
I wouldn't think about trying to defeat it.
[/quote]

I've got a car with 263 horsies and I feel like I'm driving a Metro when I'm trying to make a quick right onto a busy road from a dead stop. That feature is on the top of my "stupidest things Mazda has ever done that deserve to face obliteration" list.

[/quote]

Hey it could be worse, have you ever seen the stock intercooler on the twin turbo RX-7 (FD) ?! It is 1/4 the size of ours, and has to cool two sequential turbos on a hot running rotary! Just trying to keep it in perspective.

Anyway, please keep us updated guys. If you make it, tires and LSD clutches everywhere will be crying in terror!
 

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[quote author=C-Bass link=topic=70198.msg1225957#msg1225957 date=1172199949]
However, that is an excellent point. If you defeat this, DSC will more than likely become quite the safety hazard...It's hard to imagine exactly how it would react in emergency situations if it thinks the steering wheel is always at TDC. Perhaps the switch that defeats the angle sensor should also be set up to defeat DSC as well.
[/quote]
That was exactly my point about not defeating it. I have read that the DSC is never fully off.
 

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I bet they are smarter than this. I'm sure they will wonder why it's getting 15 psi of boost and only going 15mph. Theres always checks to countercheck the sensors. However my first guess was to unplug the SAS and hopefully it will run limp mode
 

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You can speculate all you want but until someone tries it we will never know. After looking at the way the boost is controled (a hose from the outlet side of the turbo right to the waste gate controler about 3 inches long) It looks to me like they are controling engine power by limiting throttle plate angle (fly by wire throttle, even when the pedal is to the metal the plate may only be open 25%) the ECU has complete control over throttle plate angle.
 

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Discussion Starter #16
[quote author=TruboPower link=topic=70198.msg1226264#msg1226264 date=1172206278]
I bet they are smarter than this. I'm sure they will wonder why it's getting 15 psi of boost and only going 15mph. Theres always checks to countercheck the sensors. However my first guess was to unplug the SAS and hopefully it will run limp mode
[/quote]

Are there always counterchecks? Can you think of any specific roadblocks, especially related to the gear sensor(s)?

[quote author=Byron link=topic=70198.msg1227049#msg1227049 date=1172248919]
It looks to me like they are controling engine power by limiting throttle plate angle (fly by wire throttle, even when the pedal is to the metal the plate may only be open 25%) the ECU has complete control over throttle plate angle.
[/quote]

I think that is the consensus.

Anybody with a shop manual care to shed any light on sensors/wiring/logic?
 

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I read the posts above with great interest! Not only would it be nice to defeat the torque limiter in first and second, but I would like to figure out how to get a wire for my remote start to use one or both of those switches as a safety... anyone know of a way to do this?
 

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The reverse light switch is closed only when the transaxle is in reverse, The switch for 1st/2nd gear is closed only when the transaxle is NOT in 1st or 2nd gear. There is no way of telling if the gearbox is in 3rd,4th,5th, or 6th gear using the existing switches. Both of the switches use 2 wires, neither one grounds to the transaxle body to make the circuit.
 

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Discussion Starter #19
[quote author=Byron link=topic=70198.msg1227409#msg1227409 date=1172257530]
The reverse light switch is closed only when the transaxle is in reverse, The switch for 1st/2nd gear is closed only when the transaxle is NOT in 1st or 2nd gear. There is no way of telling if the gearbox is in 3rd,4th,5th, or 6th gear using the existing switches. Both of the switches use 2 wires, neither one grounds to the transaxle body to make the circuit.
[/quote]

So, just to clarify, the total signal options are: reverse, 1-2, and 3-6? Is the 1-2 switch also closed when the car is in reverse? If so, I can't see any harm to closing that switch. I guess all it takes is jumping the 1-2 switch wires and see what happens. Where exactly on the trans is that switch?

I really wouldn't anticipate there being an ECU counter-check on that signal, but I guess it is possible (through speed and RPM).

Also, the final drive change doesn't occur until 5th (right?) so the switch would not be to recognize that.

Also, when you say that neither grounds to the trans body, what does that imply? Any significance?

I am liking this...
 

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[quote author=Byron link=topic=70198.msg1227049#msg1227049 date=1172248919]
You can speculate all you want but until someone tries it we will never know. After looking at the way the boost is controled (a hose from the outlet side of the turbo right to the waste gate controler about 3 inches long) It looks to me like they are controling engine power by limiting throttle plate angle (fly by wire throttle, even when the pedal is to the metal the plate may only be open 25%) the ECU has complete control over throttle plate angle.
[/quote]

You've hit the nail right on the head here man. I truly think that the throttle plate is causing all of the issues in terms of power limits in at least gears 1 and 2. As well the plate, so I've heard, closes as much as 50% in the upper revs. Hence why the car falls on its face in those high rev ranges. Someone.. begi w/xede, cobb, cp-e NEEDS to gain control over the throttle plate position! At this point that is more important the boost pressure, air/fuel or timing. IMO
 
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