Northern_aqs

Good day. I’m finally at the point in my rebuild where I must install the harness to move forward. Honestly, I’ve been putting it off because of concern to making new problems trying to fix old ones.

I have a Kroon harness on hand which looks like a perfect reproduction of the factory harness for my 87 turbo (they didn’t try to reproduce the cracked insulation thankfully). I don’t recognize some of the connectors (the one pictured) but any input would be appreciated.

I have the intake off still and have left things like the knock sensor, cycling valve and reference sensors plugged in or pigtailed. The hope is that because the Kroon uses the factory connectors and wire colours, I can replace the sensors (I have new for everything ahead of the firewall) as I go, then peel the harness back to the big rubber grommet.

It appears that the harness has a connector to the fuse panel but I haven’t traced the original yet; does this go under the dash or along the firewall?

Would anyone advise for or against using dielectric grease at the plug in connections?

I will also be replacing the battery/starter ground harness but plan on building it myself.

Any wisdom as I go through this would be appreciated.

Mystery connector

Millermatic

Under the dash (through the firewall).

From memory... it might go to the ceramic "hockey pucks" and thermoswitches that go to the cooling fans. Which on an '86... are located under the dash on the passenger side. For some reason.

That harness looks a lot cleaner than the one I got from LR. You had to re-use part of the existing harness. Here's mine before I wrapped it. One of the more nerve-wracking things I've done to my car. To be fair... it was well made. Just wish it had been a "total" replacement. Getting that mess through the "snorkel" was a major PITA.

Don't think you need the dielectric grease.

Definitely redo the starter and battery cables. Mine were so cracked bare wire was showing. In multiple places.

Northern_aqs

Thanks. The mystery plug connects to the fuse block in engine compartment under a plastic shroud.

The Kroon harness is complete including the rubber grommet thankfully. When I installed my VEMS system it was a pain to fish the wide band plug through. This time I’ll notch the grommet to fit the plug.

Millermatic

My other guess is to the ignition switch. It's now bugging me I can't remember where that goes.

Northern_aqs

Ok, so I have the factory harness removed and everything is lining up to install the Kroon save for the pictured connectors below (one is the original, two is the replacement).

For those performing the same project in the future, removing the two zip ties behind the glovebox for the holding the abs/chassis harness in position and the spring-steel bracket for holding the back of the glovebox makes it much easier to get the engine harness.

The only difference I’ve seen so far between old and new is that the original has a clip built in to it to affix to a metal bracket adjacent to the abs computer where as the new one doesn’t. I’m not sure about the function of this circuit as there is only a 4 pin terminator attached to it.


Original

Replacement

Tom M'Guinn

Those pins come out very easily once the cover is off. You could always re-use the old housing with the new pins. It clips onto the back of the glovebox spring clip in early turbos, and in the corner of the metal frame that holds the dme/klr in later cars. I'm guessing Kroon would want to here about that discrepancy. They are pretty focused on making it a dead ringer for the original.

Northern_aqs

Thanks Tom. The pin numbering and wire colours match once I cleaned it off. I’ve transplanted the terminator over to the new harness and it plugs in only one way, so it took out the guesswork. I will let Kroon know, they have done an excellent job of reproduction already, but I understand their standard is a 100% match.

As an aside, thank you for your excellent write up on the oil filter console reseal, it made that job very straightforward.

black944 turbo

Good luck with this, it is not a job for the faint of heart. I just finished swapping my harness Thursday.

Northern_aqs

Thanks. So far I removed the original and have it hanging beside the replacement to match all the sensors up. I’m replacing everything so it makes it a bit easier. Still a project outside of my usual comfort zone though.

I decided to order OEM battery to starter and starter to alternator harnesses but they are out of stock from Porsche in North America. Now I’ll be waiting for shipment from Germany. I was going to make my own reusing the original connectors off the old harness, but couldn’t get them apart without mangling them.

Millermatic

I went so far as to buy the cable I needed to make mine. As I recall... it got to be enough of a headache to source the rest of the parts... that I just bought an OEM harness. I love DIY... but I have no regrets on that one.

Black51

Could be a good time to pull the engine and do some WYIT work.

The harness replacement would me much easier this way.

Northern_aqs

The bottom end only needed an oil pan gasket and changing the rod bearings on spec as the car has less than 40,000 miles still.

I have however, as part of this refurb did a bunch of WYIT jobs that made access for the harness easier:

1. Rebuilt the head
2. Replaced the turbo
3. Replaced every hose and every sensor
4. Replaced the Ac system
5. Venturi delete
6. Resealed the engine (b/s, crank, oil console)
7. Replaced water pump
8. Replaced mounts
9. Swapped to a full manual rack

Millermatic

Switch #4 to “replace compressor” and #9 to “rebuild rack twice” and add “drink too many beers” and “lose a fair amount of blood” and it sounds like my refurb!

At least until I got to “diagnose loud drivetrain noise above 50mph.” Then it went off the rails... and I learned how expensive a “cheap” Porsche could be. But it has been fun.

Northern_aqs

There are some common themes in many of our cars. It’s not an if I need to diagnose strange sounds, but when.
I keep telling myself I would be bored if it wasn’t a challenging car.

944..JUT

Hey what is that metal bracket behind glovebox is it nec


Located behind glove box
essary