Notices
928 Forum 1978-1995
Sponsored by:
Sponsored by: 928 Specialists

Help on electrical

Thread Tools
 
Search this Thread
 
Old Aug 15, 2002 | 12:10 AM
  #1  
Dozman's Avatar
Dozman
Thread Starter
Addict
Rennlist Member

 
Joined: Aug 2001
Posts: 1,047
Likes: 1
From: Land of many Potholes, Michigan
Angry Help on electrical

Well, I was in the process of removing my rear bumber to fix my tail lights (one was so tight in the assembly, I couldn't remove it no matter what) with the help of Bergstsm. I was removing my brains (The shark brains!), to install my FVT performance chips thast came with my donor shark.
On one brain the two green wires are for the lower octane loop. But on the Jetronic (inner) brain there is two brown wires with molex connectors that are not connected. Can anyone pipe in and tell me what these are for?

TIA

John D.
'85 928 Auto, Black
Reply
Old Aug 16, 2002 | 12:01 PM
  #2  
WallyP's Avatar
WallyP

Rennlist Member
Rennlist Site Sponsor

20 Year Member
 
Joined: Jun 2001
Posts: 6,469
Likes: 13
From: Ball Ground, GA
Post

Low Octane Adjustment.

Don't connect them.
Reply
Old Aug 17, 2002 | 12:13 AM
  #3  
Dozman's Avatar
Dozman
Thread Starter
Addict
Rennlist Member

 
Joined: Aug 2001
Posts: 1,047
Likes: 1
From: Land of many Potholes, Michigan
Post

Wally,

The set of brown wires on one brain, and a set of green wires on the other brain are for the octane loop? I always thought that there was only one set of wires (the green wires) were for the octane loop.

Thanks for the update.

John D.
Reply
Old Aug 17, 2002 | 12:28 AM
  #4  
Greg86andahalf's Avatar
Greg86andahalf
Three Wheelin'
 
Joined: Jan 2002
Posts: 1,560
Likes: 2
From: Maryland
Post

Dozman,

GO to this thread <a href="http://forums.rennlist.com/cgi-bin/rennforums/ultimatebb.cgi?ubb=get_topic&f=14&t=002152&p=" target="_blank">octane loop thread</a>
and scroll down to my pic near the bottom. There is a pic of the brown wires for the octane loop. I'm not sure what the green ones are, the brown ones should be the only octane loop.

Greg
Reply
Old Aug 17, 2002 | 03:12 AM
  #5  
Dozman's Avatar
Dozman
Thread Starter
Addict
Rennlist Member

 
Joined: Aug 2001
Posts: 1,047
Likes: 1
From: Land of many Potholes, Michigan
Post

Thanks Greg on the pic.

Now is there a confirmation on the green wires off of the other brain, as to what they are for?

John D.
Reply
Old Aug 17, 2002 | 08:32 AM
  #6  
Greg86andahalf's Avatar
Greg86andahalf
Three Wheelin'
 
Joined: Jan 2002
Posts: 1,560
Likes: 2
From: Maryland
Post

Dozman,

I'll look in my EFI test plan book. Can you email to me a pic? I'll trace it down for you.

We're not talking about the green O2 sensor wires, are we? Large black rubber plug on them.

Shoot me a pic, if you can.

Greg
Reply
Old Aug 17, 2002 | 01:40 PM
  #7  
Greg86andahalf's Avatar
Greg86andahalf
Three Wheelin'
 
Joined: Jan 2002
Posts: 1,560
Likes: 2
From: Maryland
Post

OK Doz,

Here is what I learned from the Test Plan book and a quick look at my car.

The EZF control unit is the brain with a large connector and a vacuum line connector. It has two Green w/blue stripe wires for the Low octane loop. These wires piggyback the temp I sensor and when connected, send a 0 ohms temp I signal to the brain. (side-note, if the temp I sensor is defective, (as in shorted accros the terminals), it's the same as having the Low Octane Loop connected all the time!


The LH control unit next to it has two brown wires for the Low octane Loop. The schematic shows that one of these brown wires is ground. The other is labled "Low Octane Loop"

On my car, the green/blue wires are completely taped up in the wire harness. I didn't know they were there untill I started fishing for you today.

The brown wires on my car are exposed.

I'm sure that both sets of wires should be left un-connected for normal driving.

The picture I referenced which I posted on the other thread is referring to the green/blue wires. I, and others, have told people to look for brown wires. Both green/blue and brown sets are Low Octane Loop, but the book refers to connecting the green/blue wires for Low Octane Loop feature, and leaving them unconnected for normal driving.

Greg
Reply
Old Aug 17, 2002 | 03:19 PM
  #8  
Dozman's Avatar
Dozman
Thread Starter
Addict
Rennlist Member

 
Joined: Aug 2001
Posts: 1,047
Likes: 1
From: Land of many Potholes, Michigan
Post

Thank's a ton Wally, Greg and everyone who posts here.

Greg, Thanks for the reinforcement. Wally, I didn't doubt you at all. I was concerned maybe we were on two different pages. I guess I was on the wrong page, and you are on the right page.

Wires taped up, and tucked away.

John D.
Reply
Rennlist Stories

The Best Porsche Posts for Porsche Enthusiasts

story-0

Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look

 Verdad Gallardo
story-1

10 Porsche Colors That Have More Personality Than Most People

 Verdad Gallardo
story-2

Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod

 Verdad Gallardo
story-3

10 Reasons I Hate Going to the Porsche Dealership (& the 1 Reason I Stay)

 Joe Kucinski
story-4

Porsche Shakes Up The Nürburgring Lap Record Table Once Again

 Verdad Gallardo
story-5

6 Ways the Porsche 911 GT3 S/C Redefines Performance

 Joe Kucinski
story-6

10 Wildest Homologation Specials Porsche Ever Sold

 Verdad Gallardo
story-7

Super Rare RUF BTR III Comes Out of Hibernation, Looking For a New Home

 Verdad Gallardo
story-8

10 Porsche Opinions That Can Start a Fight

 Joe Kucinski
story-9

One-Off Porsche 911 S/T Takes Inspiration From Famous '70s Race Car

 Verdad Gallardo
Old Aug 17, 2002 | 05:38 PM
  #9  
Erik - Denmark's Avatar
Erik - Denmark
Burning Brakes
 
Joined: Apr 2002
Posts: 881
Likes: 0
From: Denmark
Question

Low Octane Adjustment.
Don't connect them.

--------------------
Wally,
Why do you say that?
Reply




All times are GMT -3. The time now is 08:13 PM.

story-0
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look

Slideshow: Porsche's latest electric Cayenne Coupe blends dramatic styling with supercar acceleration, turning the brand's midsize SUV into a 1,139-horsepower flagship.

By Verdad Gallardo | 2026-04-27 19:39:30


VIEW MORE
story-1
10 Porsche Colors That Have More Personality Than Most People

Slideshow: Porsche's wildest paint colors aren't just shades-they're full-blown personalities on four wheels.

By Verdad Gallardo | 2026-04-27 19:38:13


VIEW MORE
story-2
Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod

Slideshow: The last of the Speedsters doesn't just close a chapter, it makes quite the bold, air-cooled statement.

By Verdad Gallardo | 2026-04-22 17:55:04


VIEW MORE
story-3
10 Reasons I Hate Going to the Porsche Dealership (& the 1 Reason I Stay)

Slideshow: Going to a Porsche dealership may not be the dream experience you expect it to be and these are the reasons why.

By Joe Kucinski | 2026-04-21 13:54:19


VIEW MORE
story-4
Porsche Shakes Up The Nürburgring Lap Record Table Once Again

Slideshow: Porsche just proved-again-that precision engineering can outrun brute force at the Nürburgring.

By Verdad Gallardo | 2026-04-18 20:27:02


VIEW MORE
story-5
6 Ways the Porsche 911 GT3 S/C Redefines Performance

Slideshow: Six reasons why you will love the Porsche 911 GT3 S/C and 1 reason you will hate it.

By Joe Kucinski | 2026-04-14 10:21:39


VIEW MORE
story-6
10 Wildest Homologation Specials Porsche Ever Sold

Slideshow: Some of the most desirable Porsche models are those that were sold to the public solely for homologation purposes.

By Verdad Gallardo | 2026-04-08 09:54:26


VIEW MORE
story-7
Super Rare RUF BTR III Comes Out of Hibernation, Looking For a New Home

Slideshow: The lone BTR III-spec Targa features rare RUF engineering with a 430-hp turbo flat-six and fewer than 30 miles since its rebuild.

By Verdad Gallardo | 2026-04-06 20:03:25


VIEW MORE
story-8
10 Porsche Opinions That Can Start a Fight

Slideshow: If you want to start a debate with a Porsche friend, these 10 opinions are a great way to get started.

By Joe Kucinski | 2026-04-02 16:53:02


VIEW MORE
story-9
One-Off Porsche 911 S/T Takes Inspiration From Famous '70s Race Car

Slideshow: A one-off Porsche 911 S/T created through the Sonderwunsch program pays tribute to a little-known 1970s race car from the Camel GT Challenge.

By Verdad Gallardo | 2026-03-30 19:44:11


VIEW MORE