Originally Posted by tabetha

To put it bluntly, THEY ARE FULL OF SHIT.
They either know nothing about cars or about this one, it is thier job to fix it, I would offer to replace the original headunit back and tell them you want your money back.
The fuel pressure is not going to be affected unless you are running out, running it low does no harm whatsoever, unless it picks up crap from the tank, but won't suddenly spit it's dummy out, when you fill it up.
What would have been told it what you expect from a comedian, and it would be very funny, but not in this instance, it's crap.
tabetha