2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

Tachometer and Electronics

Thread Tools
 
Search this Thread
 
Old 06-22-08, 01:47 AM
  #1  
Full Member
Thread Starter
 
drchronic's Avatar
 
Join Date: Jun 2008
Location: Ca
Posts: 107
Likes: 0
Received 0 Likes on 0 Posts
Tachometer and Electronics

Hello, I am new to RX7's and rotary motors. I just bought an '87 RX7 and it needs some work. My tachometer only works some times and when I looked under the dash I saw that some tard removed the stock wiring harness for the ECU and wired a new molex connector on it. There is a ton of needless spaghetti wiring down there too so I can't make heads or tails of it. Basically I want to know it the rotary motor can take an aftermarket tachometer, or do I have to buy something special?
Old 06-22-08, 10:28 AM
  #2  
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
You should fix the damaged wiring first before trying to modify it. Who knows what's been done and to what end...Stuff like that leaves you at the side of the road.

As for the tach, almost any aftermarket tach will work fine as long as it can be configured for a 4 cylinder.
Old 06-22-08, 06:03 PM
  #3  
Full Member
Thread Starter
 
drchronic's Avatar
 
Join Date: Jun 2008
Location: Ca
Posts: 107
Likes: 0
Received 0 Likes on 0 Posts
Yeah the old molex connector for the ECU is just hanging there and my car has a bunch of wire caps on it. It's a horrible mess, do you think I should even try to make heads or tails of it or just replace the entire wiring harness? My tach decided to work this morning If I replace the harness I'd like a good one, what do you recommend?

BTW I thought that the firing order was closer to a 6 cylinder than a 4 because each rotor has 3 sides. Am I mistaken?
Old 06-22-08, 10:00 PM
  #4  
Top Down, Boost Up

iTrader: (7)
 
RotaryRocket88's Avatar
 
Join Date: Mar 2008
Location: San Diego, CA
Posts: 8,718
Likes: 0
Received 6 Likes on 4 Posts
There are 3 sides per rotor, but only 2 are used during a full revolution of the eccentric shaft.
Old 06-22-08, 11:37 PM
  #5  
Retired Moderator, RIP

iTrader: (142)
 
misterstyx69's Avatar
 
Join Date: Sep 2005
Location: Smiths Falls.(near Ottawa!.Mapquest IT!)
Posts: 25,581
Likes: 0
Received 131 Likes on 114 Posts
To the Poster of this Thread..Please,Oh God Please!..just listen to what Mr Aaron Cake has to say.He does know his stuff..Trust him!..
Old 06-23-08, 03:27 PM
  #6  
Full Member
Thread Starter
 
drchronic's Avatar
 
Join Date: Jun 2008
Location: Ca
Posts: 107
Likes: 0
Received 0 Likes on 0 Posts
Well on the electronics side of my car it looks pretty bad so where should I look for a mid to high grade wiring harness? I once heard that there was a company that made custom one's and actually printed the function of each wire on the ends and shielding. It takes the hassle out of wiring diagrams etc. (Although this was for old muscle cars)
Old 06-23-08, 09:53 PM
  #7  
Senior Member

iTrader: (1)
 
ramello's Avatar
 
Join Date: Mar 2002
Location: Carlsbad, CA
Posts: 580
Likes: 0
Received 0 Likes on 0 Posts
sounds like your thinking of painless wiring company
the harnesses they make are only for the other components of the car like power windows etc. they do have ignition and some of that wired in but it sounds like you need the motor harness which the only ones painless make are for like you said older muscle cars
Old 06-24-08, 09:48 AM
  #8  
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
There aren't any aftermarket harnesses for the 2nd gen that are not designed for standalones. That is to say, no stock replacements. The dealer will charge about $700 for a new one. If you can find one in good shape used, then go for it. But keep in mind that these are 20+ years old and many are in very poor condition.

Or, you could get as set of ECU plugs and splice them back into your harness if the damage is only concentrated around the ECU.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
TeamRuffRacing
Adaptronic Engine Mgmt - AUS
1
09-30-15 08:13 PM



Quick Reply: Tachometer and Electronics



All times are GMT -5. The time now is 01:11 PM.