Porsche 928 Electrics

Electrical information & supplies for late model 928s

                Porsche 928 Who Are We Wiring Diag. Primer 928 Electrics Doc Electrical Supplies Contact Us

Sharktoberfest 2005
My 928 Projects


THERE IS NO SUBSTITUTE....                       










My fantastic 1994 928 GTS......                

Probably the best Grand Touring car ever made...

"No car as fast is as luxurious - and no car as luxurious is as fast"

The previous 928 S4 model established the 928 as the fastest volume production car in the world. It's still one of the very fastest cars around and can happily cruise at over 150 MPH all day long, (if only there were somewhere in the US where you could legally or practically do this...).

The 928 model was launched in In 1978 and that year it was named "European Car of the Year" the first time this honor was awarded to a sports car. Fast forward 15 years to the last and greatest 928 model built - the 928 GTS.

The GTS has an all aluminum 5.4L  V8 engine, producing 345 HP and 395 Lb/Ft of Torque. Most 928's were manufactured as automatics with a very nice Mercedes 3 and later 4 ratio transmission. However my car is a rather rarer manual transmission. It has all the usual features, 4 wheel ABS, dual airbags, massive brakes, traction control, Fully independent suspension, dual zone air conditioning, leather electric 12 way memory seats with heating and much more...

In short its barely bested today for comfort, equipment & performance by the very latest modern high end sports cars well over a decade after the GTS model was introduced by Porsche. Meanwhile my car is often mistaken for a new model from Porsche - this almost  30 years after the basic body style was introduced - this was clearly a car ahead of its time and also timeless in its basic design. I challenge you to find another car from 1978 that still looks contemporary today...

When the 928 was launched as the flagship model in the Porsche lineup it was not very well received by Porsche purists who thought all Porsches should be small, rear engined and air cooled. Although successful enough at attracting new luxury car buyers to the Porsche brand - an initial lack of interest in used models from enthusiasts meant many cars were sold cheaply and yet the high costs of maintenance (it's still a supercar!) meant that sadly many 928's were not well looked after and are beyond recovery today. 

Now that all new Porsche models are water cooled and Porsche's move into SUV's is now the major complaint of the purists - the 928 has taken its rightfull place amongst the storied Porsche family lineup. Even die hard 911 fans now concede it was always a great car - not a replacement for a 911, No - it was really always complementary and in a different market segment of performance and comfort - a real long distance GT cruiser.

As Scott Farragher says in his book  'Porsche - The Ultimate Guide'  - ('everything you need to know about every Porsche ever built')

"The 5.4-liter GTS with 350 horsepower, is probably the best production Porsche ever made, and possibly even now the best GT coupe ever produced"

My Car:

I purchased my car in April 2000 in Evansville, Indiana after hunting for the right car for 3 years. For a Porsche 928 GTS you have to be ready to travel to where the cars are since there were only about 410 GTS's ever imported into the USA (only 140 in 1994 model year).

I spent several years getting the car into top mechanical shape - catching up on some lapsed or poor maintenance.

I've subsequently made numerous but mostly subtle changes or enhancements to the car and I have documented these updates on my Porsche 928 Projects pages... These modification fall into the categories  of Driving, Safety, Convenience, Maintenance, Entertainment & Cosmetic....

My Car was voted the "Peoples Choice Best Of Show" at Sharktoberfest 2005

The view most people see:

In implementing these projects I became (by need) something of an expert on the 928's electrical system and spent enough time staring at the schematics to understand what they were 'saying'. As an electrical/electronics engineer I had a distinct advantage over most owners - but it was still a lot of work. This provided the knowledge to answer many peoples electrical questions on Rennlist, Pelican & Reutterwerk (Porsche enthusiast web forums). In time I came to realize I was answering the same questions over and over again. Even the people who had paid literally hundreds of dollars for the factory manuals, couldn't understand much of the electrical information they had purchased. This was my motivation to create the Porsche 928 Wiring Diagram Primer document. Having sent this out for review - it was clear that it answered only a single question - "how do I read the wiring diagrams?"  The next questions were typically: "now what?" "how is it supposed to work", "how do I test it", "where do I connect to <insert part>?"

In short it was clear I had only addressed a small part of the need...

It has been a long quest since then - an it is by nature a work in progress - more detail can be added over time - but it is sufficiently complete as a framework to be useful now for most owners. I think everyone will find lots of new information on operation/function, techniques, reference documentation.

I have been very pleasantly surprised at the very obvious depth of thought and innovation that Porsche's engineers put into the designing & building of these magnificent vehicles. The initial implementations and evolutions across all systems have been overwhelmingly positive with very few retrograde steps over the 17 year life of the car.


Copyright (c): Alan Moore 2006, 2007, 2008, 2009       Page Updated: 04/03/2009