black944 turbo

Have you searched for 944 s3 instructions? These issues have come up several times in the past.

Fronkenstein

Not S3 specifically but I have Hollyoak's cheat sheet.

Ok times up. Give minutes of forum, eh-hem "searching", and I am back to reading schematics.

Either; a) I have a wrong / missing connection; b) the speed sensor is sick or; c) the DME is bad (which I am doubtful of).

Fronkenstein

PerryB

When you replaced the speed and reference sensors, what brand did you use?
I had a problem with FAE brand sensors not working, even though they passed all the test described in the workshop manual.

Perry

Fronkenstein

Genuine Porsche sensor

Fronkenstein

So if anyone wants a full pinout of the DME connector and all the gory details including the wire colors here you go:

944 S3 wiring change chart (PDF)

944 S3 wiring change chart (Excel)

Fronkenstein

Fronkenstein

So I found a very important missing bit of info. It seems that DME pin 27 requires Term 15 power aka switched +12V. This is provided via the 14 pin DME connector that is under the dash on the passenger side.

This 14 pin connector is primarily used to provide the diagnostic port access to the DME. However pin 7 of that connector goes to DME pin 27 requiring switched +12V DC.

To make matters worse the wire at pin 7 is black. We en-gi-neeeers here in the US typically assign the color black to carry "ground" NOT +12VDC. The common exception being household AC wiring.

Following the route pin 7 of the diag port feed which was like going to grandma's house via Alice in Wonderland with a little detour at Homer's Odyssey.

Without power to pin 27 the DME is only half awake and it will appear as though you have a bad DME relay. Then after jumping the relay, testing crank position sensor output all is good. So you check for switched ground at DME pin 36 (pin 85 DME relay) and it fails and then you are left thinking you have a bad DME.

I wasted a lot of time chasing that. I should have read all the pin definitions on the DME. Anyway it all works now and she runs

Here is a summary of the wiring changes needed to get the 968 mill running in a 944 chassis:

1) DME pin 27 = switched +12V DC (Term 15). You will have to find a convenient source of clean switched +12V DC. I would not use anything that feeds a motor.

2) DME pin 36 = pin 85 of the DME relay via DME connector pin 7. First you need to remove the hardwired ground from on 85. Cut the brown wire at E22 leaving a pigtail to solder another piece of brown wire long enough to reach the DME connector pin 7. Be sure to put a piece of shrink tubing on your solder joint. Push the new brown wire through the small firewall plug next to the main harness port.

Remove a pin socket from an old porsche electric connector such as an old power window connector that is made just like the DME connector. Then solder the pin socket to the brown wire and install the pin socket at pin position 7 of the DME connector.

Don't forget to terminate the other brown wire going to chassis ground with shrink tubing.

3) DME pin 18 = constant +12V DC from fuse 7 via DME connector pin 12. First remove the red/black wire pin from E35, then remove the yellow wire pin from J33, then terminate the yellow wire pin with shrink tubing, then plug the red/black wire pin into J33.

I will update the documents I shared.

Yes you read correctly, SHE RUNS!!!

Auf wiedersehen,

Fronkenstein

JWebber

Glad you got it figured out . I thought it was strange when I first got into German cars , the difference in wiring colors vs American wire colors . But almost 30 years later I am used to " brown is ground " . I`ve picked up several nick names here where I live due to my wiring skills in the VW world , but with a little time I should be able to tell you wire colors and pinouts for Porsche harnesses from the top of my head .

Fronkenstein

"brown'd is ground" - I like it. yeah what I really love is when companies like Detroit Diesel use all violet wires in a fuel injection harness. If makes for such wonderful troubleshooting. At least Porsche uses varying colors. It's a matter of US versus DIN standards. After this little escapade I will have the DIN wiring standard and colors embedded in my head forever. I can still see the CE schematic in my mind eye.

Fronkenstein

Fronkenstein

It looks like I am going to pick up another 968 so if you know anyone who wants to do an S3 let me know.

Fronkenstein

Fronkenstein

Well the old girl has a new life. Banging on all 4 cylinders after replacing 2 bad injectors.

Fronkenstein

Fronkenstein

Hey just wanted to malign a parts vendor - CARiD. They're a drop-ship entity and I will never use them again. The returns process is ridiculous and from what I can tell their team is based on Bombay (Mumbai):/ So if you're shopping ebay beware the better price unless you're 100% sure what you're buying will fit. I feel victim to an incorrect pay number from Hawk Brake which I purchased via CARiD.

Fronkenstein

Tiger03447

Glad to see that you're making progress on the beast, Fronky..Who did you use for the brake line vendor when you bought the Earl's brake hoses? My front hoses are wrong for my car. They are for the later calipers, and I need some for the early ones..metric bubble flare on the caliper end. My hoses have the inverted metric flare..Stuff happens..Thanks for the Carid tip.

Fronkenstein

Tiger,

Are you sure there is a difference between early and late calipers (assuming you have Brembo calipers)? I have yet to see a caliper with concave DIN openings. Even the floating calipers on a 944 NA are convex at the caliper. My turbo and carrera/boxster calipers are convex.

Anyway I went directly to Earl's. I am considering on having them make me 10 sets using banjo connections which eliminates the worry of whether they are convex or concave, plus you have more flexibility with routing. The fronts will be standard length but the rears will replace the entire chassis to caliper hardline. There is no reason to have them anymore and they are a bummer to find or bend yourself.

I would be selling the non-banjo set for $150 and the banjo set for $200. Potentially less if I can get a good enough discount.

Fronkenstein

Tiger03447

Thanks Fronky for the head's up on the hoses..I will check the calipers again. These are just stock early calipers. I spent about an afternoon trying to chase down a metric 10mm inverted flare fitting to a 10mm bubble flare fitting. They are made in SAE, 3/8-24 to metric bubble but not in metric to metric. I'll have to check the calipers on the '89 parts car I have..Thanks again..

Fronkenstein

Yeah even Brakequip and Earl's don't carry them. You have to make it with a tubing stub.

Fronkenstein