ive got the famous 'hesitation at 3800 rpm', and i need to know what i have to reground in the engine bay, and where to put all the wires.

 

Search for it. "3800 hesitation" would be a good set of terms to start with. There's a ton of stuff. You want to fix your existing grounds, not just add random new grounds.

-=Russ=-

 

my one friend regrounded his engine bay on his 300zx, and he said he just added new grounds...said something about the electrons finding the better path and following that. i myself figured you should remove or fix the old ones, but i cant find them, so...advice?

 

If you want to reground stuff and aren't heart set on using a specifc kind of wire you should bum around a stereo shop. They should have wire scraps in all sorts of gauges and lengths

 

thats not what i asked...ive got 10 feet of 8 guage JL wire, i just need to know where to put it...i dont know what components i need to ground, and i dont know where the original ground wires are

 

READ--------------------------------->http://www.mirror.wreckedyouth.com/man/

That is a link to the FACTORY SERVICE MANUAL.

Drop the 'tude and search the FAQ in the top of the section. there is MORE THAT ENOUGH ANSWERS. If you still cant figure it out, try an advanced search with your question. RX-7 are not 300zx There is not a generic fix. But there is an easy one, if you get off your butt and look.How many threads do you plan on making with the same problem?!

 

I ran a ground wire from my boost sensor to the water filler neck,and it took care of all my hesitations .

 

That fix is a factory service bulletin for all 86 models. There was a TSB about that, but it only pertains to 86 models.

 

the archive has a stickied thread on this with pictures, check that

 

Sorry I was just trying to be helpful, maybe you should search next time so you don't run the risk of that happening again.

 

aaron cake has a writeup coming out soon about how to reground our cars, ETA, ask him.

 

Just adding new grounds is a waste of time.

As you suspect, you need to fix the existing grounds since if the existing ECU ground aren't decent you can add a million extra grounds and never fix the problem.

Long story short is that the hesitation is generally fixed by regrounding the pressure/boost sensor. Brown/white (or brown/black) wire if I recall correctly. That wire is the main sensor ground and ties into the ECU ground which is on the top of the engine under the intake. That's the ground you are most concerned with. Next ground is at the starter, and at the bottom of the driver shock tower. Those three are most important.

Check the factory service manual for the rest...

Yes, I have a writeup coming on this but it won't be any time soon. I need a stock car that I can take pictures of without the intakes and such on...

 

i found the ground under the intake going to the firewall. my one question is though, my car is an N/A, and everyone keeps mentioning the 'boost sensor'...if im not mistaken, a non-turbo car would not have one? also, is the brown/black or brown/white wire on the cpu? and if so, where would i trace it to in the engine bay so i can clean the connection? also, where is the starter located, and do i have to get under the car to find the ground for that and for the driver shock tower? thanks

 

Buy a good multimeter (Fluke).

Check resistance to ground at multiple points on the block, chassis, alternator, etc to the battery. If you find a large variance at a certain point, you found a ground problem.

This is an abridged/generic method to finding ground problems in any vehicle.

FWIW: That JL Audio power wire kit should have come with a grounding bolt. USE IT! It makes a difference. In my experience, I've seen a 1v increase due to that grounding bolt. Now obvioulsly you can't use the bolt everywhere, but if you are grounding something and can use it - do so.

 

LOL. This is thanks to the English translation of the Japanese service manuals...

Technically we are referring to the MAP sensor on the passenger shock tower that all 2nd gens have. However in the factory service manual, this sensor is called a "boost sensor" in the NA section and a "pressure sensor" in the turbo section. Go figure. I always make the distinction since they are different part numbers.

The factory service manual is available for download in the FAQ. It contains all the wiring diagrams and shows you where the starter is. It's a must have if you are going to be doing any service on the car.

If you want to cheat, you can ground the boost sensor right at the sensor itself as the ground wire is available at the plug. However you really should deal with the main ECU ground on the engine. It is not the wire that goes to the firewall, so you need to remove the intake to access it.

 

where do i find that service manual? i tried searching for it in the 'FAQ' tab at the top of the site but it didnt work.

 

https://www.rx7club.com/showthread.p...18#post5131218