Tim Bertrand

Has anyone ever seen plug wires interfere with the operation of a Stewart electric water pump?? We recently had this happen (when the engine was running - it would shut the water pump OFF) - found out it was the plug wires.

0xenocron

How would the Spark Plug wires shut off the Pump? Or how did you come to that diagnosis?

The Stewart if I am not mistaken has its own pump controller...so the pump controller is told to be ON, and then it slowly ramps in the voltage to bring the pump flow up gradually.

I have a car on a stewart that RANDOMLY just wont start, even when the controller is told to turn on using a low side output from the ECU. What's odd is that if you kick the Rad Fans on manually via switch, this sometimes kicks the fuel pump controller into turning on...some sort of fly back voltage issue that we havent totally figured out.

SO...its possible you have a plug wire or plug putting voltage into the rest of vehicle and causing some interference there, but I would suspect you might see OTHER issues as well as a result of this?

Tim Bertrand

Amazingly enough - we changed the wires and had no issues after that. We ran multiple races and were experiencing overheating issues. We changed literally everything. It was literally the last thing we didn't change. The way we finally figured it out was we started the car - and took off the radiator cap, and noticed that we were getting 0 flow to the overflow can. We shut off the motor, and the pump turned back on. It was the oddest thing. I have no idea technically how it would have happened, but we literally had no other running issues while this was happening. I've now seen it all.