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Discussion Starter #1
Was under the hood checking the grounding and such thinking i might try to help the the throttle lag by grounding the TB. I measured from the TB to the chassis ground and got 700K ohms, so i measured from the TB to the negative battery post and got the same. Looking at the threads about grounding and such I notice that in the pics of other cars compared to mine the 05 throttle body appears different. From the pics it appears that other years have something attached to the front of the TB where the ground wire is attached. On my 05 the front is clean. I didn't see any wires on the TB except for the plug in connector so i just picked a random bolt off of the TB and measured that to ground. Is this correct? All my other measurements were less than 5 ohms.

Has anyone with an 05 grounded the engine bay and have some advice or pics to share?
 

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Grounding from any spot on the TB to any chassis ground should accomplish the desired effect.
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It will accomplish nothing. If you ask me, "grounding kits" are just a waste of No. 4 wire that you can buy at Home Depot cheaper.

The throttle response it dictated by the PCU and the servo motor on the throttle body. - nothing more.
 

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He is asking about doing it himself. Grounding kits are not a waste of money, but don't expect unrealistic things from them. You will not get 20hp out of it. You will however get better throttle response and a smoother idle.

If I "asked you" then I would be getting misinformation. I have done a number of grounding spots to my car, and have lowered the resistance as a result.
 

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If I "asked you" then I would be getting misinformation. I have done a number of grounding spots to my car, and have lowered the resistance as a result.
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The only "misinformation" that you have is from the person who told you that wiring the TB housing to the engine block would actually do anything.

Just for a laugh, I'm going to play around with this and see what I can come up with...
 

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Discussion Starter #7
^ exactly I'm not using a kit either i was going to just ground one point with my own wire, as it is the only point with a high resistance to ground. Thanks for the info dabears
 

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^ exactly I'm not using a kit either i was going to just ground one point with my own wire, as it is the only point with a high resistance to ground. Thanks for the info dabears
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i still need to ground out my TB as well...
 

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he's not wiring the tb to the engine block.
more like tb to ground.
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The engine block IS part of the ground - just like any other part of the chassis.

I still think it won't do jack sh*t. We'll see what a little experimentation tells us...
 

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Discussion Starter #10
it may not noticeably reduce throttle lag, but it will provide a better ground, the tb is not part of the engine block
 

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The engine block IS part of the ground - just like any other part of the chassis.

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the engine block ISNT part of the ground, perhaps it is MADE part of the ground by a current grounding wire, but technically, the only real ground that offers the least resistance is the negative battery terminal. even the grounding wire from the negative terminal to the chassis can become corroded and not allow for a complete ground. then, all sorts of crazy shit goes on electrically. if you do a search for grounding mods tons and tons of threads will come up, this has been argued to death, and some people notice some changes for the better, some dont. its all very car specific.

im going to be doing some upgrading of by "big three" wires hopefully so i can get some better response from my sound system, and remove a weird ground loop issue i have with the amp right now,

is that a placebo, and wrong? no, everyone will say upgrading the big 3 makes a difference, but because your dealing with purely electronic components you can notice the difference much better. whereas with the tb ground, you hafta notice the difference in how the engine responds, and that is MUCH harder to notice.
 

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the engine block ISNT part of the ground, perhaps it is MADE part of the ground by a current grounding wire, but technically, the only real ground that offers the least resistance is the negative battery terminal. even the grounding wire from the negative terminal to the chassis can become corroded and not allow for a complete ground. then, all sorts of crazy shit goes on electrically.
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First - let's clarify what "ground" really is - in DC terms anyway. It's a conductive mass of sufficient size such that it can dissapate a residual electric charge, AND it must be at 0 VDC potential.

So, that means that the engine block and/or the chassis will serve as a good ground source, so long as the connection is good. There should be a metal strap bonding the two together anyway, because it's a good idea to use the same ground for the entire electical system.

To get back to my point - connecting a piece of wire from your TB housing to the chassis will do absolutely nothing. There is no potential difference between the two. And besides, the throttle servo is located inside the housing, and there is no electircal connection between the motor winding, it's casing, and the TB housing.

I snooped around with a multimeter and an oscilloscope, and there is no electrical explanation for the improved throttle response that some have mentioned. For a laugh, I put an alligator clip from the TB housing to the chassis and drove to work. It behaves the same as it always has.

But that's just one opinion - take it as you will.
 

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Geez . . . not this topic again . . .

Grounding the TB does nothing. The servo mechanism that actually operates the throttle does NOT ground through the TB. It grounds through the wiring harness connected to it. Thus, grounding the TB assembly does not improve the ground of the TB servo.

Grounding the TB assembly to improve engine response is like grounding your steering wheel to improve the responsiveness of your radio controls.
 

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just want to clarify im not disagreeing with you guys, nobody ever really hopes for a big improvement using grounding wires. i just want my sound system to stop buzzing when i turn off the car.
 

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I 100% agree with Burnsey....because he's the only one that backed up his points lol.
 

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Discussion Starter #16
I was not going to ground the the throttle body housing. I had asked earlier about where everyone was grounding it since their pics weren't all the same. You could still run a ground through the wire harness
 

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I was not going to ground the the throttle body housing. I had asked earlier about where everyone was grounding it since their pics weren't all the same. You could still run a ground through the wire harness
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What I'm saying is that there is no need to ground the throttle body - it already is. A lot of people have been connecting their throttle body housing to the chassis, which is absolutely pointless.

Adding an additional ground circuit to the wiring harness could do more harm than good. By adding another conductor to the harness, you could create a "antenna" like affect, as it would pick up on RF from the ignition system, etc, and screw up the pulse-width modulation signal to the throttle body servo motor from the ECU.

Basically, the stock TB wiring is fine. To make any significant changes to "throttle response", you'll have to re-program the throttle pedal position-to-servo position mapping in the ECU.
 

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Discussion Starter #18
Doesn't Mazda do any test driving of the vehicles when they manufacture them? What I'm saying is how they can ship these cars with throttle lag, have TSB to flash the PCM and get no changes. Though i have learned to drive the car to avoid experiencing the lag its still there after having all updates made to it. As a manufacturing engineer my ass would get chewed if i knew that our products were like this.
 

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There's are there 3 simple rule to grounding.
If one is designed in, leave it there
If its there, keep it clean and tight
Don't add grounds.
I train on marine power electrical systems, and as equipment gets more complicated, these rules become more important. The Mazda 6 is a complex piece of electronics / software, utilising such as CAN bus for communications. This means that the grounding is not simply DC, but a mixture of all sorts of frequencies. To find any component with 700K to ground, then sticking a ground onto it is asking for trouble.
Some guy / team in Japan has worked all this out, don't muck it about.
 
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