The pump controller works off what rpm the engine is running at or tach signal. I have the same controller on my car. I figure you have a bad signal going to the controller. If the controller does not see a signal it does not tell the pump to run. Or you have the max output for the pump set at to high rpm.

http://aeromotiveinc.com/wp-content/uploads/2009/12/16306.pdf

Also you may be losing key on power to it while it is running thus shutting the pump down.

Last edited by Twin Turbo Mower; 10/06/12 10:07 PM.