944 Tach/RPM troubleshooting help
 

Hoping someone from the message board could help me to troubleshoot a tach/RPM problem I'm having. I just completed a 2.8 Stroker conversion on my 951 and it started right up, although I have no reading on my tachometer. The speed sensor is working correctly because I'm getting an RPM reading from my laptop via the piggyback computer that I installed (Mafterburner) and the car is running fine so far. So it appears that something got disconnected from the Tach itself?? If anyone has some advice on how to troubleshoot this problem I'd appreciate it.

thanks in advance.

Brent
86' 951 2.8 Stroker + every mod I could think of. (20mins of runtime so far =)

Looks like your tach signal comes off of pins 11 and 21 on the DME. Pin 21 is bifracated with one wire going to the knock sensor pin 9. The other goes to a four pin plug next to the DME/KLR. Pin 2.

Pin 11 on the DME goes straight to the tach through pin 1 on the same four pin plug.

SoCal Driver.

Thanks for your help that's it, I found a Red 4 pin connector next to my DME computer that I though was some extra option I didn't have. I checke pin 11 from the DME and sure enough it goes to pin 1 on that connector. Now if I could only find out what that 4 pin connector connects to, I did find a 2pin white connector that appears to fit but it isnt' really keyed for the 4 pin connector so I'm kind of worried about plugging something in wrong. In any case thanks again for your help I'll see if I can verify the other connector. Let me know if I can do anything for you in return, need any parts for your porsche or good deals or Momo parts?

Thanks, Brent

I finally found the other end of the red 4 pin connector, I had tucked it out of the way when I was pulling the wiring harness out of my car for the engine rebuild. Anyway, stupid mistake not to document that. Thanks again for helping me solve the problem.

Brent

Plug and Play!