Wiring Harness Install
#17
Question on the the power supply wire where the 14 pin connecter is and jump terminal. I just installed mine this weekend but it seems that red wire which attaches to the terminal is too long so I had to almost bend in a 1/2 turn to make it work. It also doesn't seem like it would come from the other side either as there are already two wires there taking that spot... any thoughts on this or anyone experience this dilemma?
Thank you!
Thank you!
#18
I think they wanted a downward loop so water (spray) doesn't run down the cable to the terminal connection point at the jump post. This way it just drips off the bottom of the loop.
Alan
Alan
#22
Sean installed one on my GTS several years ago.
ran better, volts were slightly up.
He’s putting one in my 79 this week. (I’ll let him post pics)
On a car that has always been garaged and only has 67k miles, it was amazing how corroded it was.
Especially at the 14 pin connector and at the alternator. (Outside of the harness was clean as a whistle and looked pretty decent)
ran better, volts were slightly up.
He’s putting one in my 79 this week. (I’ll let him post pics)
On a car that has always been garaged and only has 67k miles, it was amazing how corroded it was.
Especially at the 14 pin connector and at the alternator. (Outside of the harness was clean as a whistle and looked pretty decent)
#23
Chuck, my car is an 87 and many years younger, but it's been garaged and spent 30 years in Southern California. She now has 117K and has been extremely pampered since day one. The wiring and main harnesses are now crispy and due for replacement. I am going to replace the front harness next year, can't wait!
#26
Thx Sean.
Yeah, that's some crazy stuff!!
It's funny, this car has NEVER really been in the elements, but apparently father time has taken it's toll.
The GTS was only in good weather (at least in my 10 years of ownership) and still benefited from a new harness even though the factory harness looked pristine from the outside.
I'm not going to tell folks to go run out and get one just to get one, but unless your car has been stored in a museum, there's probably some corrosion in the factory harness to some degree.
Yeah, that's some crazy stuff!!
It's funny, this car has NEVER really been in the elements, but apparently father time has taken it's toll.
The GTS was only in good weather (at least in my 10 years of ownership) and still benefited from a new harness even though the factory harness looked pristine from the outside.
I'm not going to tell folks to go run out and get one just to get one, but unless your car has been stored in a museum, there's probably some corrosion in the factory harness to some degree.
#28
Chronic Tool Dropper
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There are likely several more green wires like this buried inside the sleeve. Many of us look at the sleeve and think that since it's looking great, the wires and insulation inside must be similarly great. We make judgments on those inner conductors based on the little tails we see near the jump post. Some clues: That fat brown wire that runs to the jump post used to be red. That fancy factory accordian pleating on the insulation where it does that pretzel twist to the post is really cracking, allowing air-rain-wash-water-etc into the copper core to corrode from the inside. The ends you see are the least heat affected sections in the harness. Follow it across the front of the engine where it's "cooled" by speed- and fan-drive radiator air, and on to where it winds back under the exhaust to the alternator, then back next to the block and over the crossmember by the motor mount heat shields, then relatively unprotected to the starter area. If you think the part you see by the jump post is "OK", know that the exposure to heat and the elements in the rest of the harness are in half the "OK" condition of what you've been looking at on top.
Failure modes include the copper deterioration that is illustrated in SeanR's "green wire" example. Once that cancer starts, it grows through the cable out of sight inside the insulation. For higher-current conductors like the normally-yellow 50 circuit to the starter solenoid, the resistance turns to heat when the starter is cranked. All the power used to run the car, save feul pump and injectors, and cooling fans on S4+ cars, passes through that formerly-red primary feeder to the jump post. Resistance there turns into heat, and eventually the insulation fails. Other circuits served by the harness get the benefit of connection to that un-fused battery feeder. More wires melt together, with more hidden damage in other places.
Advice: save yourself now while you can. A myriad of minor electrical bugs are magically cured with conductors that conduct and connectors that actually connect, protected by insulation that insulates. Modern wiring materials are a lot more durable than when our factory harnesses were fabricated, suggesting that my 30 year old factory harness should be easily outlasted by a modern replacement. I won't live long enough to worry again about the harness condition.
Don't forget the harness on top of the engine either, the one with all the sensors and the injectors connected. It's the same age and has enjoyed the same or hotter conditions, nestled there under the intake.
Failure modes include the copper deterioration that is illustrated in SeanR's "green wire" example. Once that cancer starts, it grows through the cable out of sight inside the insulation. For higher-current conductors like the normally-yellow 50 circuit to the starter solenoid, the resistance turns to heat when the starter is cranked. All the power used to run the car, save feul pump and injectors, and cooling fans on S4+ cars, passes through that formerly-red primary feeder to the jump post. Resistance there turns into heat, and eventually the insulation fails. Other circuits served by the harness get the benefit of connection to that un-fused battery feeder. More wires melt together, with more hidden damage in other places.
Advice: save yourself now while you can. A myriad of minor electrical bugs are magically cured with conductors that conduct and connectors that actually connect, protected by insulation that insulates. Modern wiring materials are a lot more durable than when our factory harnesses were fabricated, suggesting that my 30 year old factory harness should be easily outlasted by a modern replacement. I won't live long enough to worry again about the harness condition.
Don't forget the harness on top of the engine either, the one with all the sensors and the injectors connected. It's the same age and has enjoyed the same or hotter conditions, nestled there under the intake.
#29
Thx Sean.
Yeah, that's some crazy stuff!!
It's funny, this car has NEVER really been in the elements, but apparently father time has taken it's toll.
The GTS was only in good weather (at least in my 10 years of ownership) and still benefited from a new harness even though the factory harness looked pristine from the outside.
I'm not going to tell folks to go run out and get one just to get one, but unless your car has been stored in a museum, there's probably some corrosion in the factory harness to some degree.
Yeah, that's some crazy stuff!!
It's funny, this car has NEVER really been in the elements, but apparently father time has taken it's toll.
The GTS was only in good weather (at least in my 10 years of ownership) and still benefited from a new harness even though the factory harness looked pristine from the outside.
I'm not going to tell folks to go run out and get one just to get one, but unless your car has been stored in a museum, there's probably some corrosion in the factory harness to some degree.
This harness through me for a loop once I got it removed and compared it to the other 3 CIS (US and ROW) I have on hand to match. Some of the early cars had additional connections for odds and ends that other cars didn't have and I usually just build a complete one with all the connections and let them know there may be a couple connections that they don't have. This version was slightly different than all the rest so I'm glad to have it on hand to match with. Porsche was inconstant development in the early stuff so I never know what I'm going to find. Some cars have the A/C idle increase components and wiring built in, some of them have it as a separate harness, this car doesn't have anything of the sort. Going forward I'll have the owners shoot me a couple of pictures of areas and I'll better know what version to build.
Here ya go Chuck.