soontobered84

Is the infamous green wire present on all MY 928's?

ZEUS+

'78 to '84

85fortheDrive

I've heard tell of this green wire. What is the gist of it?

Thanks!

Tim

soontobered84

Thanks Zeus!
The green wire goes from the computer inside the car across the engine to the distributor. It is famous for breaking down. When breaking down, it can create all sorts of really funky symptoms that make diagnosis difficult.

Steve J.

It's also famous for costing a hundred bucks. I'm going to try replacing the brittle wire while re-using the molded connectors. It's a shielded wire.

John Speake

I have considered offering replacement green wires, but made using shielded PTFE wire. Anyone interested ?

Price ? Sensible answers please ! :-)

Daniel Dudley

If you can make them at a reasonable cost, I can see you doing well. I used to see this on other Ljet cars , and I think it should be a routine service item. It is worth noting that sometimes the wire will look perfect, but internal degeneration of the actual wire has occured without affecting the insulation. Very confounding. You see it a lot on Marelli ignitions also.

John Speake

Hi Daniel,
I see they are around 100USD (plus postage ?) I have an old one here (courtesy of Marton).

The only special part is the distributor end. I will investigate whether it is possible to re-use some of those parts.

Is the usual problem shorts or open circuits ?

JP Rodkey

There was also a rash of factory new wires that were produced improperly with the leads switched. Causes the car to idle high and a lot of people spent hours trying to diagnose the problem never imagining a brand new Porsche part could be the culprit. Personally, I got two of them in a row - even after the problem was known and thought to be resolved.

John Speake

OK JPR, I won't copy one of those :-)

Brett928S2

Hi

Umm John or anyone else ...is this the same green wire that you CAN connect down by the fuse board to give 6 degrees of retard for bad fuel etc ???

As I was going to connect my race controller to it to use the retard at high revs and lots of Nitrous....are you saying that if its altered in any way it will make idle etc strange ???

All the best Brett

PORSCHE 928 S2 AUTO V8 4.7 LTR 1986 IRIS METALLIC BLUE WITH X-PIPES ,RMB ,PROMAX CHIPS, KICKDOWN SWITCH, K&N, WIZARDS OF NOS - NITROUS KIT 150 HP JETTING - 505 BHP / 500 FT LBS TORQUE
PCGB UK 928 FORUM MODERATOR - Email managingdirector@pchealthcare.co.uk

John Speake

Hi Brett
No, totally different green wire...

Steve J.

Green wire

Brett928S2

Hi John

Phew...thanks

By the way my car is TOTALLY better with the new MAF from you

All the best Brett

SharkSkin

My understanding is that that green wire has to have a specific impedance -- so there's more to it than just "shielded wire". Since impedance is not something you can measure with a DMM, this may not be a good DIY candidate. Since we don't know the dielectric constant of the insulator between the inner and outer conductors(well, maybe someone does), you would need a function generator and scope plus a good understanding of analog theory to characterize the existing wire and then characterize any candidate for replacement.