quickgt

I just bought a 83 944. I made the dumb mistake of buying without it starting. Guy said the fuel pump was not working. I got it home and checked the pump and running a wire from the battery to the fuel pump runs the pump. So I hard wired the pump to the battery just to start the car. Well, the car wont start. Im getting spark and getting fuel by running a wire from the fuel pump to the battery but its not starting. I cracked the lines open behind the fuel regulator and fuel squirts pretty good. Pulled a spark plug and grounded it and had a blue spark. Im stumped. Im getting spark and fuel but its not starting. Any ideas? Thanks in advance

odonnell

Dme relay?

mel_t_vin

While hot-wiring the fuel pump may get you pressure at the rail, it will not guarantee you spray at the injectors. In order to get an injector to spray, it needs a pulsed ground signal from the DME [digital motor electronics, AKA computer].

Pull the fuel rail with injectors attached and have someone crank your engine. Got spray? No...most likely a bad DME [injector circuit]. Swap in a known working unit to test.

pops 83 944

Or reference sensors could be bad, I would go to http://www.clarks-garage.com/ and bypass the dme relay and test out the sensors. Let us know what you find and we can go from there.

william_b_noble

also, do you have compression? a broken timing belt will make it not start

944_nut

The injector wire harness commonly gets brittle and fails at this age, I would eliminate the harness as a problem before you go shelling out cash for a DME rebuild/purchase. If you are getting spark, it is even more likely that that it is fuel specific (which doesn't rule out the DME of course).

Also, try starting the car with one injector plug left unplugged. The injector drivers in the DME can go into an overload state if too much current is being drawn by the injectors. This happens if your fuel pressure at the rail is too high. By unplugging one injector, you reduce the load on the DME drivers by 1/4. It would be nice if it were something as simple as a bad fuel pressure regulator.