Tanabe

1st of all I actually SEARCHED to save us all from the headaches.

My FD had a pain in her *** for a while now. I had the all famous "3000rpm hesitation" going on. It occured mostly while cruising on the freeway @ around 60-80mph while barely touching the gas. The car would jerk back and forth until I punched it then all was ok. My other problem was the boost spiking from 6000rpm to redline... like 15-16psi. The car sounded like it was backfiring so I just let go of the gas 'cause I don't wanna be going in for ANOTHER engine. I don't have too many mods so I like to keep it around 11psi.

I just got a new engine dropped in a few months ago and it only has like 4k miles on it. When I got the engine I also had the usual fixings: plugs, oil, oil filter, radiator flushed, injectors flushed, tranny fluid, etc. Once the symptoms started I figured it was maybe my spark plug wires or coils because it hesitated like a bitch and I have like 25k miles on my Nology wires. So I double checked w/ my mechanic and he mentioned one of the Mazda newsletters. I looked through the books and sure enough it was a problem (found in like the 97 book having to do with all the FDs) with grounding the negative battery cable. Symptoms were exactly like I described.

Now I was on to something... I went down the street to the local RICE shop looking for the hyperground system which was like $125... I was like F**k that! I made a quick call to my good buddy rotor-rooter for a 2nd opinion...

Within seconds I was outta there. I 1st went home and jumped on the forum and found some interesting threads.

Thanks to damian and James Paventi for their detailed pics and write-ups.

Then I went to Kragen and bought a 60" 4 gauge battery cable and a couple connectors for the grand total of $15. After some cutting, splicing, zip ties, and screwing... within an hour I WAS DONE!!!

pic 1: I ran a wire parallel to the negative battery wire but then grounded it near...


pic2: the power steering fluid


while I was there I re-did the back ground from the UIM to the body...


and the finished product from the top view...



I took my baby for a test spin around the neighborhood and from the second I stepped on it my baby was back!!! I tried to redline her and sure enough all the power was back with NO more breakup, no hesitation, and no boost spiking!!! I haven't got on the freeway yet but cruising around the hood I didn't feel any jerking so I guess she's all better.

I grounded what I thought would make the biggest difference and so far it's great... definately worth my $15

I'm glad there's such good things in this world like friends and the RX-7 Forum. Thanks everyone!

Mike

Batmobile

Good write up dude but you called RotorRooter for mechanical advices? I'm surprised he didn't tell you to check your BOV

MaxBoost

You need five grounds like the Hyper Ground Kit...lol

FormerPorscheGuy

Good job, I never thought about grounding it to the power steering pump, hmmm.

DaedelGT

I'd just ground the Alternator. I really don't see a need for the PS pump.

Tanabe

hey whatever works now I can drive like a maniac again

r0t0r-rooter

Congrats with the car! I guess there's nothing left to do but buy my hi-flow cat* I'll even give you a break on the price if ya rig up some grounds for me.

BTW, my second idea was to vent the stock BOV


*or polished uim

DaedelGT

I really like that negative terminal you bought. From Kragen as well I assume? I want to replace mine is why i ask.

Tanabe

yeah i actually bought them (gold plated) from kragen a while ago when my stock ones were falling apart (maybe a year ago) since then they're still as clean as when i bought 'em maybe 10 bucks each... i don't remember

pshaw118

I wish I had some money to buy some parts so I can post something like this.

gnobesav

The grounding kit is one of the best things I ever did for the driveability of the car. You call it the 3000rpm hesitation though, and that still exists. The problem you got rid of was the light throttle bucking. My car was missing many of the factory grounds, so the problem was really bad, it made people think I didn't know how to drive, heh.

rotorbrain

my car bucks. . . i guess i better do all this stuff. rock on!!!

paul

s13sr20

the grounding kit did nothing for my 240sx...technically lost 1hp on the dyno too (but 1-3hp variations on the dyno are typical).

adam c

iTrader: (2)

I attached 2 grounding straps. One to the elbow where it attaches to the throttle body. The other to the crossover tube mount. Boths straps connect to the frame. Really easy to do. It definitely helped with the 3k hesitation.

88IntegraLS

Wow, this is exactly like the FC 3800 rpm hesitation caused by the same issue: poor grounding. Of couse we have six ports which will not open from time to time, and dirty secondary injector issues . . . and air flow meters!