Welcome to everyone, my name is Marlon Gaitán from Nicaragua and I am reviving a Jaguar S-Type 3.0 V6 in 2000, the car starts, runs and all goes well, but there is a problem, the fuel pressure has to go down with it At the same time, when it starts and takes about 20 minutes of work, the pressure starts to go down on the fuel level until it goes out, it is noticed that the pressure starts to go down when the steam purge management valve starts to increase. for example: the valve has 30% and the fuel pressure drops from 50 or 60 psi to 47 psi and the valve reaches 80%, the pressure drops to 25 or 30 psi, the fuel pump also starts to to work with a modulated work cycle of 75% at a time low to 6% and gradually ascend without stopping until 50% and from there on, just speed up completely, I have a code that always appears and is P1237 and revises all wiring and electrical part of the rear module, f box usibles, relay and fuel pump and everything is good, i hope to help me please i need to revive the jaguar and this is the last problem that i could not fix.