Throttle Body Ground (by loudboxer)

Just tried this MOD. There's definitely something going on. It's more responsive. HP/Tq is the same there's just no lag now when I hit the gas. My wife noticed the car seemed 'peppier' and I didn't tell her that I did this mod so I know it's not my mind playing tricks.

update: okay now after about 300miles or so the car feels back to it's normal self. Thinking about disconnecting the battery and resetting the computer (stepping on the brake while disconnected, right?) but don't want to have to reprogram my radio stations (ughdance)
 
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Is this something that is a problem as soon as you buy your 3? I have my 2006 M3 with about 6000 miles, and i bought it on June 18th, with 2 miles on her. I'm going to do this, but I just wanted to know if it will make a difference so soon in the car's life?

Thanks,

Josh
 
racerboy777 said:
Is this something that is a problem as soon as you buy your 3?
Click to expand...

It's a general "issue" of all ETBs (electronic throttle body) on any car. Users report a more responsive throttle and better shifting transitions after doing this.... which is basically grounding the TPS (throttle position sensor) on the TB.
 
Ground the coilpacks as well, find the point where the negative battery cable connects to the unibody, and clean the paint from under the contact point so it is touching bare metal (smear some dielectric grease over it after you reconnect it so it doesnt corrode)

Basically you want to improve the grounding of the entire car, and randomly running grounds wont help (many people do this). You want the ground path from the important sensors and the coilpacks to have the least resistance possible. You really dont need anything heavier than 10 or even 12 gauge, but 8 gauge has the best "look" to it for most people. I typically use 12 gauge black wire to match the factory wire harnesses as close as I can. This isnt the only ground that these things have, you are only doing this to lower the resistance of the ground path, and this is only a miniscule load. Its not like this wire will be the only ground and its a 110V. Its a ground assist and its a 12V system, in fact a lot of these sensors only see 1.5-3 volts.
 
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I like the mod so far. It's nothing major, but for less than $5 it's worth the difference. The throttle responds alot smoother and changes as fast as I need it to. Hopefully it will be a good assist to the CAI.
 
The throttle body on a Mazda3 is controlled by an electric servo. Since the throttle body is "floating"(meaning not hard grounded), static charges can accumulate on the TB and effect the accuracy of the servo. When you connect a ground wire, you eliminate those excess charges and allow the throttle to operated to the best of its ability. Meaning no extra power, but a throttle that moves like you want it to.

There has been talk of the computer re-learning and making up for this change. I don't think this will be an issue since the computer can't create and place a static charge on the TB. If you think that it's not working as well after a few hundred miles, you probably have just gotten used to the way it operates.
 
To whoever says that the ECU re-learns and adds the lag back in,

Why not try undoing the mod and see if there is a difference, removing 1 side of the grounding wire and temporarily ziptieing it cant be that hard now can it?
Take it for a drive, any difference?
Then redo the mod and drive.
If after that it's still laggy, then reset the ECU.

This thread definitely cleared the fog surrounding this mod for me.
After the positive results with the airbox mod, I am definitely going to try and do this to my friends 6s ATX. I will get video.
 
AgSubmariner said:
The throttle body on a Mazda3 is controlled by an electric servo. Since the throttle body is "floating"(meaning not hard grounded), static charges can accumulate on the TB and effect the accuracy of the servo. When you connect a ground wire, you eliminate those excess charges and allow the throttle to operated to the best of its ability. Meaning no extra power, but a throttle that moves like you want it to.
Click to expand...

It's true that the TB is normally ungrounded but, with all due respect, assuming that your explanation is correct, why wouldn't Mazda's engineers include a separate OEM TB ground wire to eliminate those excess static electricity charges to insure optimal throttle response? After all, the 3 has very sophisticated engine control mechanisms in place and if the simple addition of a short piece of wire would further improve driveability, surely the engineers would not have left it out. Particularly if, as it's claimed, that little length of wire makes a difference many people can discern.

Although I have a Protege, my wife has an '06 3i and I might just try the mod to see for myself if it works, although I'm highly skeptical of obtaining an improvement.
 
The engineers at Mazda are pretty good about catching things, but electronic throttle control is fairly new. Cable controlled throttles don't have this issue, so I wouldn't have though about it either.

Take a look at the engineering on the the Mazda3 trunk. It took them until the '07 models to put a handle, so you don't have to pinch your fingers under the lid. Simple thing, but just not on their minds.
 
goldstar said:
It's true that the TB is normally ungrounded but, with all due respect, assuming that your explanation is correct, why wouldn't Mazda's engineers include a separate OEM TB ground wire to eliminate those excess static electricity charges to insure optimal throttle response? After all, the 3 has very sophisticated engine control mechanisms in place and if the simple addition of a short piece of wire would further improve driveability, surely the engineers would not have left it out. Particularly if, as it's claimed, that little length of wire makes a difference many people can discern.

Although I have a Protege, my wife has an '06 3i and I might just try the mod to see for myself if it works, although I'm highly skeptical of obtaining an improvement.
Click to expand...


Same reason your rear view mirror is 80mm tall instead 100mm. Because people will still buy it if we stop spending money on that part and improve the car more where people notice. :)
 
I'll have to try this out before I head up to New York and see how it works out over the long term; roughly about 5-6k miles. I know people have repoted that the car relearns and compensates, but it just sounds like a case of getting used to the way it drives. Once I get back I'll post results. Also, wouldn't this mod technically work on the 5... or is the TB not the same as it is in the 3?
 
This has no practial on or off paper application.

You have added a wire and i your brain, it feels faster...
 
Noob question, Do you need to do anything before you do this so ou don't get shocked? and can teh wire heat so much it causes fire?
 
elderlycoffee said:
Noob question, Do you need to do anything before you do this so ou don't get shocked? and can teh wire heat so much it causes fire?
Click to expand...

No and no.
 
No.

The wire doesn't carry any current. It just dissipates static electricity that builds up in the plastic intake system.
 
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