Car Owners Hub UK - Built by Drivers, for Drivers

Hello there! I'm experiencing a problem with my remapped b47 engine. Whenever I floor the accelerator or put the car in full load mode, it goes into limp mode and displays the code p0087, which means fuel rail pressure is low. I don't think it's the map because I've experienced the identical problem on two other remaps. My mapper informed me that the automobile barely produced stick figures and that if he requested additional fuel, the pressure would drop.
I would be grateful for any assistance.

Why did the mapper map it and then leave it mapped when there is clearly an underlying issue? Put it back to stock and fix the real problem.

Here we are, still attempting to figure out how to get the automobile back to its stock condition.

Having a place with ISTA scanning capabilities and then running test plans on the generated codes would be ideal. The use of generic P codes could lead you in circles.

Putting the map back on, creating the code again, and scanning through ISTA for an accurate resolution would be the best course of action, right?

I take it that the standard map doesn't provide the error code? The fuel pressure can be checked by doing experiments in ISTA.
Considering what you're stating, it does seem like the map is wrong if there are no codes when standard.

It sounds just like a map.
Does the mapper create a custom map for the vehicle, or is it an already-made download?