Mazda 3 Owners
 

I had seen a post here a while back re: running a ground from negative battery to throttle body.

Was going to wrench on the 911 yesterday but was feeling under the weather so to feed my jones I dug up an extra battery ground cable and tossed it on my 3.

The car does idle much smoother and throttle response feels much better. Obviously not a HP mod but it does improve drivability.

Even if it's purely psychological who cares, costs nothing and took 10 minutes.

no kidding? got a pic?

I haven't done it yet to mine (I never drive it, and my girl seems to like the throttle lag, she can't tell why I complain), but yes, it should significantly help things. The throttle body is not electrically grounded through the plastic intake piping OR the block, and there's only a tiny gauge ground wire in the harness. Tossing a decent true ground cable on there helps.

There's actually about 6 places that could use real grounding, lots of the "ricers" with the M3s run a grounding spider right off the negative battery post, with 5 or 6 decent sized (10 gauge) cables all over the engine bay.

More than you could possibly care about this modification:
http://www.mazda3forums.com/index.php?topic=8848.0

I did that to my 3 when i first got it. I agree, the idle does seem smoother. I would also suggest getting a set of Goodridge brake lines, makes a world of difference.

I don't remember the car, but I saw a dyno test where adding additional ground wires added a few HP. It also reportedly improved response. I guess maybe you're all not crazy.:)

I wonder if this will work for my MazdaSpeed3?

I think the Speed3 has a metal intake, so the throttle body is well grounded. It's only the N/A version that has plastic on both sides of the TB which prevents a decent ground.