Hello, Read the article in clarks garage about the DME Relay and how to make a jumper for temp. use. You should get about 1/16th" jump in the TACK gage with the engine turning 200 rpm on start. All we know is that you have a 944 with 64K, which 944, and year do you have? Does any lights work on the car? Check all fuses, some may look good but still be bad. I hope your fuse box itself doesn't have shorts in it. Mine did and I had to replace it on an 85.5 na. You are leaving a lot of information out that we need to help you. What have you already done on the car? Have you drained out the old fuel for one?
DME Relay Information and Testing
Cheers,
Larry