Cold start on electronic pump

[Chevy Dooley]

Can anyone explaine how the cold start on a electronic pump works?
And what parts is related to this function?
What temp sensor is connected to the ecm?

Thanks

[Robyn]

The cold start feature is designed to advance the pump timing some based on the coolant temperature.
Other than the sensor, the parts involved are inside the IP.

The sensor involved is located in the water crossover at the front top of the engine (Opposite end from the upper hose outlet)

The sensor sends an electronic signal to the ECM based on the coolant temp and advances the timing accordingly.

A fast idle feature is also incorporated too

The sensor also effects the glow plug on time some too..

Hope this helps


Robyn

[Chevy Dooley]

When engine is cold, do the steppermotor moves up
or down?

[Robyn]

Not sure which way it moves.

You may be able to see the arm move if you watch it and then unplug the coolant temp sensor plug.

Unplugging the sensor will make the ECM think that it is -30 degrees F outside and the advance will go as far as it can.

Other than that, I have never given much thought to this.

Hope this helps.


Missy