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7000 ohms? That's a Hell of a lot of resistance, but WHERE did you measure resistance. I'm venturing a guess that the throttle body actuator/motor is grounded through a wire in the harness (it's mounted to a plastic intake manifold, can't really ground through that). If the resistance on THAT GROUND WIRE is really high, then maybe there's an empirical reason grounding the throttle body would help.

If you just checked resistance on one of the metal bolts that secures the throttle body to the plastic intake manifold, I'm not surprised you got that high of a resistance. Plastic makes one heck of a good insulator.
 
7000 ohms? That's a Hell of a lot of resistance, but WHERE did you measure resistance. I'm venturing a guess that the throttle body actuator/motor is grounded through a wire in the harness (it's mounted to a plastic intake manifold, can't really ground through that). If the resistance on THAT GROUND WIRE is really high, then maybe there's an empirical reason grounding the throttle body would help.

If you just checked resistance on one of the metal bolts that secures the throttle body to the plastic intake manifold, I'm not surprised you got that high of a resistance. Plastic makes one heck of a good insulator.
Yes, I just checked on one of the bolt. But I have read some previous posts said their resistance was just about 1-2k.
Thanks
 
Like I said, its a bolt threaded into a plastic manifold, resistance is gonna be sky high, but that's not the ground path the throttle body actuator follows guaranteed.
 
Like I said, its a bolt threaded into a plastic manifold, resistance is gonna be sky high, but that's not the ground path the throttle body actuator follows guaranteed.
Yes, I just wondering if I should ground the throttle body. Some post said it made their auto tranny shift smoother, that's what I'm looking for. I just ordered the cable from flex. It's cheap and risk free mod, hope it won't take long to be delivered.
 
Hello, I just joined this forum and I did the grounding of the throttle body today, and I immediately noticed engine was smoother between shifts. I have a 5 speed and before the rpms would always want to spike should I say between shifts, now everything is nice and smooth...loving it!!! :chuckles:
 
Hello, I just joined this forum and I did the grounding of the throttle body today, and I immediately noticed engine was smoother between shifts. I have a 5 speed and before the rpms would always want to spike should I say between shifts, now everything is nice and smooth...loving it!!! :chuckles:
Good stuff, but would be more helpful if you provide your car trim/year for others reference :)
 
How have I not heard of this yet? Doing this soon.
 
I did this a few days ago, first day I thought it helped on my 2008 Mazda 3s but then the next couple of days it stopped seeming to work. Doesn't seem like the ECU could compensate for something like that at all, maybe I just got used to it. Either way, for me it was a small but initially noticeable difference when not WOT shifting, mostly when shifting when the RPMs were around 4000. If driving at say 4000 rpms they drop down to 2000 very quickly, then VERY slowly go down to idle if I push the clutch in. I know that seems kinda contradictory to what I said about it not helping with WOT when shifting, but that was my experience.
 
I don't understand how this can even work. I've taken apart one of the older 60mm throttle bodies and there is no physical electrical connection between the aluminum housing and the electronics inside.
 
I did it and didn't notice a difference at all. I drove it like that for a couple months then unhooked it and didn't notice a difference either.
I guess even if it's a placebo effect for some people, something that gets you more enjoyment out of your ride for a measly $5 isn't too bad.
 
Huge difference!

I did this last night because I was noticing laggy throttle response (revving up between shifts, slow acceleration when the pedal was first pressed, etc...). It's so much better with the throttle body grounded now. Thanks for the write up.

I noticed that on this thread some people aren't noticing any difference at all. I wonder if that's just because their throttle response was better already?
 
I recently did this mod, used insulated 6 gauge wire (stranded) with coated copper connectors. I bolted them down under the top right throttle body bolt (8mm) and to the battery chassis ground bolt (10mm) on the driver's side. Vehicle is 2004 Mazda3 S hatch (2.3, 5mt)

Results certainly justify the small cost, and would justify a higher cost, really.

I can objectively say that pesky rev-up between shifts has gone away (I blame it on the crappy drive-by-wire system). Accelerate, clutch in, and the revs drop like normal. The rev-hang now feels like the *minor* rev-hang on every car, and honestly better than most IMO.

No change in power or torque.

Response seems feels a little more immediate, and power delivery is smoother and more controlled. You don't necessarily feel those specific changes; the net result is minor improvement in power/throttle smoothness- those are just the reasons behind it.


I'm of the opinion that everyone should at least try this mod. The worst that can happen is nothing happening. I suspect that many people haven't noticed a difference because of factory differences. Economy cars like Mazda don't have absurdly extreme tolerance specs, and most of us know some of our engines are weaker or stronger than others simply because of factory timing tolerances. I think it's safe to assume that trait is present in other parts of the car- this is a gross oversimplification, but you get the point. :)
 
Hi everyone I'm new I'd love to help those wanting to do tb ground I had some 4g wire and took it to my local auto shop asked if they had any connectors they put it on for free try this at most will cost 5 and the throttle body on 04-09 maz3 are located on top you'll see a flat plastic piece that goes to your battery housing to your grill right under that plastic piece is your airbox it on the lower right facing engine lol right behind the headlight on driver side ok take the engine cover off then you have more room for throttle body there are three screws one to your right top 10mm I'm pretty sure then there on about 5/8 from the bottom of the whole assembly on the left than finally there's a another one on underneath the top right very annoying to get to so now the process take a 10mm and unscrew the top right fully take it out then thanks the connector and put the screw through it the just put back so easy then go to the batteries ground yay 😊😹😂😂😂 make sure to put the engine cover on lol 😜 tighten the bolt for good connection don't brake lol recommended to disconnect the negative battery terminal when working on electrical system even ground and your off to the races it's helped alot and I hope this help to others I've notice that I've actually gotten better gas because the engine doesn't have to build up to response and I've gotten around 400 to 430 on single tank and going down hill it you almost don't use any gas I noticed that before it would eat through gas when going down hill 😉 yuck 🤢 I doordash for a living and need anything that help get more mileage lol now I am for sure free to 5 mod don't buy grounding kits please just make your own its fun if you liked this please follow me on FB or Instagram I can answer more questions if you pm me I can send a video too hope this help and voomvoom !!!!
 
What most people don't realize... and WHY this works is... your gas pedal doesn't open a carburetor the way an OLD engine does.


It's basically a Potentiometer? What is a Potentiometer? A potentiometer is a manually adjustable variable resistor with 3 terminals. Two of the terminals are connected to the opposite ends of a resistive element, and the third terminal connects to a sliding contact, called a wiper, moving over the resistive element.

The throttle valve potentiometer determines the opening angle of the throttle valve. This information is then forwarded to the control unit and used as a parameter for calculating the necessary fuel quantity. It is mounted directly on the throttle valve shaft.

I did this "trick" only this past summer (June 2023) and I was SO angry that I didn't discover this sooner. For a mere $8 in parts from Lowe's, I went with 8 or 10 ga. wire and loops (which I crimped right in their store after measuring a cut, lol), I then did the fix in the parking lot.

First thing I noticed... throttle response was SMOOTHER. Not perceived, it was. This after driving this 2011 Mazda 3i, from NJ to Florida (4 times, Florida to Texas, Florida to VT and back again). Within 2 minutes of the install, I took the car to some back winding hilly roads and it literally glided through them.

No more awkward shifts and it trying to find the right place to shift but instead, smooth higher revs and upshifts with better response, as well as downshifts and instant throttle throughout.

DO THIS FIX NOW IF YOU HAVEN'T ALREADY!!!
 
It does nothing unless you already have a grounding concern with the chassis in which case that should be addressed first.
I build custom T?B and never advise or recommend to ground them. There is no empirical reason if the T/B is functioning properly to do any grounding outside the casing!

Maybe some should first disassemble a T/B and see exactly how they work both mechanically and electrically before posting a theory?
I am surprised we don't see a member post to ground the drive-by-wire (throttle pedal controller) as well? lol
 
What most people don't realize... and WHY this works is... your gas pedal doesn't open a carburetor the way an OLD engine does.


It's basically a Potentiometer? What is a Potentiometer? A potentiometer is a manually adjustable variable resistor with 3 terminals. Two of the terminals are connected to the opposite ends of a resistive element, and the third terminal connects to a sliding contact, called a wiper, moving over the resistive element.

The throttle valve potentiometer determines the opening angle of the throttle valve. This information is then forwarded to the control unit and used as a parameter for calculating the necessary fuel quantity. It is mounted directly on the throttle valve shaft.

I did this "trick" only this past summer (June 2023) and I was SO angry that I didn't discover this sooner. For a mere $8 in parts from Lowe's, I went with 8 or 10 ga. wire and loops (which I crimped right in their store after measuring a cut, lol), I then did the fix in the parking lot.

First thing I noticed... throttle response was SMOOTHER. Not perceived, it was. This after driving this 2011 Mazda 3i, from NJ to Florida (4 times, Florida to Texas, Florida to VT and back again). Within 2 minutes of the install, I took the car to some back winding hilly roads and it literally glided through them.

No more awkward shifts and it trying to find the right place to shift but instead, smooth higher revs and upshifts with better response, as well as downshifts and instant throttle throughout.

DO THIS FIX NOW IF YOU HAVEN'T ALREADY!!!
I'd rather fashion a new hat out of tin foil than to waste my time grounding my throttle body.
 
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