[ZLRob]

I need to follow up with this thread and give it the update that it needs for anyone looking to do a Katech module.

The JMS booster is indeed THE issue causing my P2635 code. What I didn't notice at the time in the slough of old permanent codes I had stored due to a previous project I was working on in the fuel system was that I had a U042B chassis control module communication failure that has been pending and was the tell that it was the JMS causing my issue.

The moment I eliminated the JMS from the circuit and set it all back to OE connections the codes went away and the fuel system is happy as it once was.

The problem is that the JMS is meant for a single channel fuel pump, and while this is indeed a single channel technically speaking, the Katech Vaporworx controller is connected to the battery and has no way of boosting voltage that the JMS does prior to any boosting at all. I realized it when I hooked up my voltmeter to the JMS and saw that resting static voltage with the car off I was looking at 14.4 volts before doing anything at all. It makes sense now because battery voltage depending what sort of battery you run is going to be anywhere from 12.6- 13.3 volts at rest. So the moment you turn on the car there is a voltage conflict between the two pumps, chassis control communication failure code, and fuel pump insufficient flow code because they are both flowing differing amounts right out of the gate.

Happy modding guys, I'm glad this has been resolved. Fuel system looks great once again!