Maciek

I am in the midst of putting the engine out of an 86 951 into a 91 944S2. The wiring harness in the S2 was damaged by an engine fire, but I am trying to use the interior harness along with the wiring harness off the 951 engine. My problem is that the interior wiring is pretty different in the two cars. If I left wires that were supposed to run to the engine in the S2 unplugged, would this cause a problem? Has anyone done something like this before and figured it out? Any help or insight would be greatly appreciated. Thanks in advance.

nine-44

What exactly are you trying to figure out? I pulled the NA harness on mine and put the 951 harness in. Had a few things that still need to be finished, but it all layed in there fine. It should have connecting points, 14 pin by the brake booster, the DME and KLR in the foot well, and a few others in the foot well.

Maciek

Nine-44,
The S2 harness has the interior part of the wiring connected to the same harness that goes through the fire wall out to the engine. I obviously am using the Engine wiring harness off the 951 engine, but I want to keep the interior part from the S2. Is it ok if I just leave the part that is supposed to go to the engine unplugged? Will everything work? Can I just cut it off?
Thats what im trying to figure out, hoperfully its a bit more clear this time. Thanks for looking.

pikey7

If I remember, a lot of the wiring was updated after 86. the 951 harness doesn't have some of the functions of the later one. You're probably better off replacing the whole thing if possible? I think though it was mostly gauge related (oil level was one for certain!)

Maciek

So can I use the S2 harness even though I cut the part that goes to the engine? Does anyone know if it will work?

SoCal Driver

If you are also using the DME from the donor car you should be 99% there. There is a world of difference in the DME's. You really have to use the 951 DME.

You should also be using the entire vacuum control system from the donor car too. Including the idle control valve.

The tach, temp gauge and warning light, the oil pressure and warning light are the same for post 85.5 944's. Have to add the boost gauge.

mmmbeer

Get the wiring diagrams from both cars and there is (almost) no limits to what you can do.

Regards
Eirik Kvello-Aune
www.diateam.no/porsche

Tom Carson

if the engine includes the complete turbo set up you need the 951 harness and both the DME and KLR units

the wiring is completely different, pin out for AFM, TPS...you name it

IIRC the DME for the S2 has 3 rows of pin connectors and the 951 has 2 rows plus another plug for the KLR

you have a PM

Maciek

Tom,
I appreciate your help, but I think you are misunderstanding my problem. I am switching over both the DME and KLR from the turbo to the S2, but the interior wiring harness (all the wires that run to the dashboard ect.) are attached to the same harness that runs to the S2 engine. I had to cut the S2 engine harness off because it melted in a fire, so I would like to know if I can use the remaining S2 harness even though the part I do not need has been cut off.

SoCal Driver

Yes and no.

The wiring and plug going to the DME (and KLR) has to be the one from the donor car.

You can use the same instrument sensors and senders from the donor car and just catch these wires and splice them in. Oil pressure, engine temp and warning, etc.

For the irregularities such as the idle control valve and boost gauge you are going to need the factory electricals and a bit of study.

Not something easily related over this BBS.

nine-44

Ok, let me clear some things up... The guages, all but the boost guage have the wiring routed through the 14 pin plud near the brake booster. Inside the car, in the footwell at the DME there i a flat plug with(I think) 4 pin, it is the one that carries the signal to the boost guage. I'm still not too sure what your question is???????? Almost everything on the car has plugs in locations that hould be fairly safe location wise as far as a fire. Did the fire burn past the firewall boot on the DME harness? the plug is in the footwell for the DME and goes directly to the DME and KLR. I'm ure some pics would greatly help me help you. If you can't post them, Email them to me. Good Luck and hope this helps!

Chris Prack

I think you are referring to the plug under the right side of the dash near the DME. It's probably an 8 pin flat plug on the 951 harness and a 14 pin plug on the S2. Right?

Tom Carson

no...I believe those on the right side are both 8 pin flat (and neither has 8 wires)...just might not have the same wires in the connector...i.e. boost guage is there for the 951 and not for the S2

gotta have the manuals...understand the colors...read schematics...do-able...oh yeah...

it ain't rocket science

Chris Prack

OK so if they are both 8 pin connectors that makes it much easier. There is not much to understanding the colours, black is black and red is red. What's not to understand? The lack of the boost guage is insignificant, they don't work worth a damn anyway right.

I have done quite a few engine swaps and for the most part it's just a matter of getting the wiring for the tach and oil level sensor if it has one. The other thing to consider is the S2 used an igniter and the 951 does not, so a jumper for the connector will have to be made to get power to the coil.

dualblade

actually, i think understanding wiring diagrams is rocket science