It has been a while since I was at Sharktoberfest with our first prototype replacement engine wiring harness, and I can give you an update.

I was not real happy with that sub-contractor, and the wiring harness they made for me from a bad 928 harness I had sent them functioned, but looked far from original. Then I had the ever-popular change-of-mind regarding minimum order quantity and price, so we parted ways.

The next 2 wiring harness makers I have gone thru in the last 6 months have done same.

To get the minimum-order quantity that I want, and the flexibility to match all the different models of 928 engine wiring harnesses, and the quality I want - we have to do it ourselves.

That's what we are doing. Pictures below from the workbench where we are making a 1979 engine wiring harness. I have 3 of these to ship in the next week or so.

We use Bosch Modac connectors, and metric-sized copper connectors on the wires themselves. The 14-pin connector is not available anywhere, so we either re-work a 928 14-pin connector from a junkyard, or we buy an expensive 911 14-pin connector and have to re-machine it.

All wires are multi-strand copper cable matched one-for-one to the Porsche wire they replace, and where the exact replacement wire size is not available, we go up to the next wire gauge larger. All connectors have heat-shrink sleeves over them.

We have upgraded from the wire loom (sometimes called sleeving) that Porsche used that is PVC-based and gets brittle and cracks with age - to a silicone-coated fiberglas wire loom that remains flexible forever. The two largest cables in this wiring harness (to the starter and to the alternator) are also silicone-insulated rather than PVC insulated.

I'll take and post pictures of the finished units soon. By doing them this way, we can offer to make any engine wiring harness a customer sends us - and that's a good thing because there are many, many variations on this part.

I feel that this is one of the most significant threats to our 928's survival... many 928's are suffering electrical gremlins because of the increased impedance (resistance) caused by corrosion within the wire, broken insulation, cross-firing, and broken wires.

If you have an interest, or want to talk about an engine wiring harness for your year/model of 928, email me at carl@928motorsports.com or call me toll-free at 877-FOR-928M.

 

Now that you dont have to pay someone else to make them, whats the running rate for the K-jet and L-jet cars? Know a couple CIS cars in the area that could use some new wiring...

 

Dude My hats off to you my man!! I have to make all of mine for the race bikes but to take on the car.............you've got big ones buddy. If your personality is a reflection of your aggressiveness toward your work you gotta be one fun dude top wind up and let go haha. If you have them made up and I can use one I'll buy it when I go under the hood at the end of the summer. Just to have one new , solid and custom. You got my vote man.

 

WOW!

 

Nice Carl!! Hey, the critical thing IMHO is the sheath. Not heat shrink, that will become brittle. What options?

 

Mercedes used plenty of those 10, 12, 14 pin connectors, maybe their part number would be cheaper. Otherwise, plenty of nice mid-80's Benz's in the U-Pull yards.

For example, here's a 12-pin I got from under the dash on a mid-80's Benz, to make a brake light brain delete jumper:


Off topic, but I would like to find a source for the Audi style (push to release) AMP 2 term fuel injector/sensor, in both male and female, to make a L-Jet cold start delete kit. Audi charges around $10 for one!

 

Great work, Carl! I wish we had chatted last time we got together about this. I've fabbed my own as well, and currently working on a writeup (with parts list and procedure) so that anyone can roll their own. Mine is successfully installed and working (79 Euro) and I'm happy with it. Of course, it's my first effort, and any subsequent would be even better. Anyway, here are some pics:

 

Oooh nice! What did that cost ya JP?

 

Barry - at the moment, we are still only charging $449.00 for this part.

http://www.928motorsports.com/parts/wiringharness.html

Porken - It would be great if you could get me a part number off of a 14-pin MBenz part - I'd give it a try. As long as it mould mate with the female side of the connector left on the rf fender, I'd use it. Re-fabbing old used connectors is not what I want to do and takes tons of time. Remachining the 911 connectors is expensive - my cost ends up being $75 just for that male HALF of the 14-pin connector alone!

If ANYBODY knows where I can get that 14-pin connector, I'd love to hear from you. The 14-pin male-side is what we need and it has two parts: the part that holds the pins and the cap that snaps in place to cover them.

The part number of the bottom with pins is is " 9674/1 "

The black top has the casting numbers "23738/1"

...any help locating this on a Benz, Audi, BMW, etc would be appreciated. Porsche has discontinued carrying it, and the replacement parts numbers
9674 , and 23738 are not the same.

 

Total cost of parts was $80. However, I had a spare harness available, and the 14 pin terminal was intact and the pins reuseable. I also re-used the Bosch connectors for the sensors, except replaced one with a new one. The most expensive part was the heat shrink tubing. I did re-use the red insulator sleeve that runs from the alternator to the starter because I didn't need to replace it - and it's shown in the picture under the starter. It looks darned near original, and is much better than the one I removed.

 

That's about half price from OEM... I spent about $900 for the upper and lower harnesses on the motor in my avatar..... Nice work Carl!!

 

ON A RELATED PROJECT: NEED SOME HELP

The NEXT wiring harness we feel is endangering our species is the injector harness for the L-Jet cars. I get a lot of emails of misfiring or non-firing injectors attributed to this harness that is dying.

The injector harness goes through the firewall to the LH and up into the dash too. Its a bear to replace - if a replacement was available - and it is not.
But, the part of the injector harness that is inside the car is fine - and does not seem to age hardly at all. It is the typical heat/ozone/petrochemicals under hood that destroy the wiring there.

I am interested in making a replacement part for this, with a 20-pin weather-tight connector that you would cut into your car so you do not have to pull out the in-dash wiring. As a side benefit, this would allow you to DISCONNECT your injector wiring harness, and remove the motor for service with the injector wiring harness in place - sorta like you can do now with the engine wiring harness (above).

I have a 84/85 injector wiring harness here that we are playing with. At the moment, the project is stuck while we look for the following connectors:

Does anybody see and recognize these as also being on a Benz, Audi, BMW, etc? Need year and model if you recognize them. Then I can source them up.

 

Carl, those rectangular connectors are Bosch, just like the two-pin ones used for the injectors. Obviously, they go to higher pin configurations, but they're definitely the same style. AMP makes them for Bosch. When I was looking for replacement connectors, it was tough because of information overload. Hope that helps.

 

JP - I know severl sites that have a few Bosch/AMP connectors for sale.

Do you know anybody who has access to the entrie line of Bosch or AMP connectors?

 

I think I saw that three pin on my SAAB. If I have time tomorrow, I'll poke around under the hood.