MS3 Pro - Fuel Pump Won't Stop
 

Just installed an MS3 Pro into my 2000 and am having an odd issue with the fuel pump running constantly once it is triggered by the ECU.

I first noticed it with the prime when first powering up the ECU. It should run the pump for a few seconds (2-6 depending on coolant temp). However, the pump continues to run indefinitely. I changed the entire "priming pulse" table to 0's so it wouldn't prime the pump and I could stay connected to the ECU to troubleshoot the issue. I went into the "Output Test Mode - Inj/Spk" menu and tested both the coil and injectors, both of which worked as expected. I got the car started to set base timing, and it ran without issue.

I then tried testing the fuel pump from the test menu. The pump starts running when commanded, but continues to run after clicking "Fuel Pump Off". The (seemingly) only way to stop the pump from running once triggered is to power cycle the ECU.

This was not an issue on the stock ECU, it appears to be a logic issue in the MS as far as I can tell. Open to suggestions :confused: