New Member RX-7 Technical Post your first technical questions here, in an easy flame free environment, before jumping into the main technical sections.

Grounding question 86 s4 NA

Thread Tools
 
Search this Thread
 
Old 07-18-14, 03:24 PM
  #1  
Junior Member

Thread Starter
 
driftnismo's Avatar
 
Join Date: Apr 2009
Location: houston
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
TX Grounding question 86 s4 NA

I have a 1986 s4 N/A. stock.
I have cut the ground wires at the ecu to reground to "fix" the 3800rpm stutter. i noticed that there wasnt a bolt holding any grounds where aaroncakes guide said they were under the manifold. Can i ground the ecu to the floor board/chassis or does it need to be back on the block? i attached it to the bolts that hold the kick panel on (sanded them to the metal) but it wouldnt start the next day(go figure). any help would be appreciated. thanks! ps ive searched for the past few days before making the post.
Old 07-19-14, 02:09 PM
  #2  
Moderator

iTrader: (1)
 
satch's Avatar
 
Join Date: Jun 2005
Location: tulsa,ok.
Posts: 11,738
Received 11 Likes on 10 Posts
It's best to have the main engine ground grounded to the engine block. If you took a meter to the grounds you have they should read 0 volts w/key to on. If they have voltage on them then they aren't grounded properly.
Old 07-19-14, 08:45 PM
  #3  
Hey...Cut it out!

iTrader: (4)
 
Akagis_white_comet's Avatar
 
Join Date: Dec 2007
Location: St Louis, MO
Posts: 2,067
Received 291 Likes on 190 Posts
It should be grounded to the engine as Satch said. However, given the criticality of these grounds to the car's function, giving them each a redundant ground to the body, such as on the passenger side strut tower, would be a wise idea
Old 07-19-14, 09:16 PM
  #4  
Moderator

iTrader: (1)
 
satch's Avatar
 
Join Date: Jun 2005
Location: tulsa,ok.
Posts: 11,738
Received 11 Likes on 10 Posts
And when you say you cut the grounds at the ECU did you add a wire to each cut wire so as to reconnect each one to the ECU or not?
Old 07-19-14, 09:51 PM
  #5  
Junior Member

Thread Starter
 
driftnismo's Avatar
 
Join Date: Apr 2009
Location: houston
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Yessir. Basically the ground that was supposed to be on the block wasn't there. Bolt and everything is missing. So I took the two grounds on the small plug, cut them and soldered new 12g wire in there place. I grounded them to the floor board though. Obviously wrong based on the replies I received. So tomorrow I will de solder and attach longer wire, run through the fire wall to the proper grounding point. Sound like a plan?
Old 07-19-14, 10:04 PM
  #6  
Moderator

iTrader: (1)
 
satch's Avatar
 
Join Date: Jun 2005
Location: tulsa,ok.
Posts: 11,738
Received 11 Likes on 10 Posts
Pins 2C, 3G, 3A and 2R are all grounds (3A and 2R are spliced to each other).
Old 07-20-14, 10:01 AM
  #7  
Engine, Not Motor

iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,789
Likes: 0
Received 108 Likes on 91 Posts
Here's the details on 2nd gen grounding:

Proper RX-7 Grounding Procedures
Old 07-20-14, 10:24 AM
  #8  
Junior Member

Thread Starter
 
driftnismo's Avatar
 
Join Date: Apr 2009
Location: houston
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Thanks guys. Trust me Aaron I've looked at that guide for days lol. Do the other above stated grounds by satch all converge on the same ground point on the block? 2c and 2r as well I mean.
Old 07-20-14, 10:27 AM
  #9  
Junior Member

Thread Starter
 
driftnismo's Avatar
 
Join Date: Apr 2009
Location: houston
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts

Guess this explains what I need huh?
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rgordon1979
3rd Generation Specific (1993-2002)
40
03-15-22 12:04 PM
_Tones_
Adaptronic Engine Mgmt - AUS
10
05-25-21 05:37 AM
Nosferatu
2nd Generation Specific (1986-1992)
7
09-05-15 02:13 PM



Quick Reply: Grounding question 86 s4 NA



All times are GMT -5. The time now is 04:35 PM.