350 SLC 1972 troubleshooting

The distributor is rebuilt.
Just need to test it.

The distributor is back on the car,
The dwell set to 34°.

The engine is not working very well.
Poor idle and no reving.

I still have to set the timing.

But i have just checked the spark plug 5 is dry.



Spark plug 1 is still wet. Strange.

I set the timing to 34° @ 3000 rpm.

Same behavior as few days before.
Poor reving.

Cylinder 1 and 5 Are not working.

The cause was not the pertronix.
With the factory points and condenser, the engine is working only on 6 cylinders.
Just as before with the pertronix but as the spark might be more powerful it was less noticeable.


I did an injector swap between cylinder 1 and 2.
Same behavior, cylinder 1 and 5 not working.



Remember few weeks ago I did a spray test with my other ECU and all 8 injectors were working.

This time I did a single spray test on injector 1.
I put some extra fuel line and start the engine with injector 1 out.
No fuel was coming out.




Few days ago I tested the trigger contacts wire to the ecu there were OK.
I also tested the wire to injectors group 1 & 5 it was OK.

I checked the duty cycle of the trigger contact group 1 (injector 1 and 5) with the engine running.
It is around 50%. It is OK

Can it come from the ECU ?

Yes the ECU is guilty.

I put back my old ECU and ... voilà.