85 911 Carrera wont start
 

I have just completed the rebuild of my engine while stretching it to 3.4 l. The motor cranks beautifully and oil pressure came up very quickly.

However, it wont start now although it was fine when I pulled the engine.

First checks indicate that the DME does not activate the fuel pump and there is no spark activation from the DME.

The DME relay checks out OK. So does the power supply to the DME (pins 18 and 20)

I have checked the DME and everything "looks" fine.

Any suggestions or what did I overlook to connect?

RonH

For a quick DME bypass check, you can run a jumper wire from the fuse for the fuel pump (#6?) to an adjacent fuse. If you hear the fuel pump whir, try starting the engine....

JB

Thanks. Tried that but the DME doesnt activate the relay or send spark. Tried speed and reference sensors both ways but still no joy. Suppose must now partially drop the engine again and check (or replace) out the sensors. Anything simple that I have missed?

RonH