cullenwinter wrote:
I just discovered in trying to hook up the harness today that the "Auxiliary Air Valve 944.606.103.00" is different on early cars. It has a two post clip for the harness compared to the late version, called an "Idle stabilizer valve 930.606.161.00" which has a three post. Now, if I'm incorrect on this research, please let me know. Thanks
Yes the early cars run an auxiliary air valve(for cold idle) along with a seperate air valve to compensate for A/C operation. The 85.5 and up cars including 924S all combined both functions into the Idle stablizer valve. Since you have early harness run the aux air valve. This will also match with the 84 DME. My 84 944 has run an 87+ motor for 10 years now. I had the luxury of swapping the DME harness back in 2000 when I stuffed my 87 924S motor in the car. The motor and harness came from a 924S parts car I had. Anyway at the time I installed the full 87 fuel injection and the motor worked perfect. The only parts I had to adapt were the fuel lines which did not have the right fittings for the late fuel rail and the tach connection which comes from the DME harness. This did not match the connector on 84 chassis. So I jumpered it to make the tach work.
In my case I was able to use a 924S harness which is perfect since it is designed to mount the DME under the steering wheel just as it is in the 84. The 944 85.5 harness are different in that they put the DME in the pass floor board. I don't know what that does for the wiring.
Anyway this 85.5+ 924S injection has worked great on my 9.5:1 87 motor, it worked also on on my 84/87 hybrid motor (84 bottom end, 87 top end) and my 88 motor. For testing purposes I have swapped my 84 DME/AFM a few times of the years. The car always ran with no issues, but never felt quite as sharp. I always used the 85.5+ injectors. Right now I am running a 88 motor, but have gone back and forth between the 88 DME and 87 DME. The 87 DME runs a higher idle (1000 rpm vs 900 rpm) than 88 DME. I have not notice any power differences.
The reason I am using a 87 DME is that I am trouble shooting some electrical issues and have been swapping parts. My guess is my DME harness is getting old and causing problems and occasional cut out. The car runs a bit better with the higher idle since when it cuts it tends not to stall like it does with 88 DME. I probably need to go through the DME harness and rebuild most of it as age and heat I believe have taken their toll. Even so the car run great 99% of the time.
