"a DSM owner in need"

[Maxximillion]

hey guys, ive poured over this site and its amazing how much comaraderie there is for DSM owners. i've had problems and have been helped and i have helped others but now i am in need once more................does anybody have a site link or know where i can get a detailed schematic or description of a 92 AWD talon ignition system? specifically the fuel setup and the relationship between the key, the ECU, the MPI and the fuel pump. having some odd problems with the fuel pump not turning on when its supposed to. and i have ruled out most of the things that i, and a few others on this site could think of. please help keep this DSM from turning into a parts car.

Jason.
92.5 TSI AWD

 

[steve]

This is for the turbo but the basics are correct. You really should get a Factory Service Manual. All the wiring diagrams are in it.

Steve

http://www.taboospeedshop.com/wiring.htm

 

[Maxximillion]

hey steve, thanks for the schematic its exactly what i needed haven't found the problem yet though but i've pretty much ruled out the timing, fuel pump, and the MPI relay which really only leaves the ECU. if you look on the schematic, my fuel pump will turn on using the check connector. and with the key ON i've checked for power to pin 3 on the harness and i get 12 volts. now something is not activating the coil in the relay and i've checked the relay and it works. so that only leaves the grounding switch wire on pin 7. now if pin 7 grounding wire from the ECU is corroded to the point of not being able to function, would that also prevent the 12 volt starter source from triping the relay and activating the fuel pump upon cranking?

 

[steve]

The starter part of the fuel pump relay in the MPI relay is the coil between pins 9 and 6.
Pin 6 sould be grounded all the time. Pin 9 gets pulled to battery voltage when the starter is engaged. That causes current to flow closing the connection between pin 3 and pin 2. Once the car starts the ECU pulls pin 7 low to cause current to flow through the second coil (between 3 and 7) and keep the fuel pump running.

Steve