Editing Openai/69606181-ab0c-8001-96cc-1653bd658833 (section)

=== Assistant: P0087 is a Fuel Rail/System Pressure Too Low fault code. ===
P0087 is a Fuel Rail/System Pressure Too Low fault code.
In plain terms: the engine isn’t getting enough fuel pressure compared to what the ECU expects.

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==== The ECU monitors fuel pressure via the fuel rail pressure sensor. If actual pressure stays below target for a certain time/load condition, it throws P0087. ====

This usually shows up under:
* Acceleration
* High load
* Cold start
* Hard driving / towing

==== - Loss of power (especially under load) ====
* Hard starts or extended cranking
* Rough idle or stalling
* Limp mode
* Check Engine Light
* Poor fuel economy

==== ### ====
* Low-pressure pump (in-tank) or
* High-pressure pump (direct injection engines)

===== - Very common if the filter is overdue =====
* Can cause intermittent pressure drops

===== - Stuck open → pressure bleeds off =====
* Electronic regulators can fail silently

===== - Sending bad data → ECU thinks pressure is low =====
* Often sets P0087 + related pressure codes

===== - Restricted fuel line =====
* Kinked hose
* Bad fuel (water/contamination)
* Low fuel level (yes, this can matter)

===== - Pump relay =====
* Wiring voltage drop
* Corroded ground

==== If you want to be efficient and not throw parts at it: ====

===== - What RPM? =====
* Load?
* Speed?
* Fuel pressure commanded vs actual

===== - Mechanical gauge (low-pressure side) =====
* Scan tool live data (rail pressure)
* Compare idle vs acceleration

===== - Fuel filter age =====
* Fuel level
* Listen for pump priming
* Check for fuel leaks

===== - Voltage at fuel pump under load =====
* Ground integrity
* Pump relay operation

===== - Does pressure reading make sense when key-on? =====
* Any sudden drops or flat-lined values?

==== Running lean due to low fuel pressure can: ====
* Overheat pistons
* Damage injectors
* Cause detonation
* Kill catalytic converters

If the car feels gutless under load, don’t push it.

==== - Fuel filter replacement (cheap, often overlooked) ====
* Fuel pump replacement (most common true fix)
* Fuel pressure sensor (moderate cost)
* Wiring repair near pump or rail

==== If you want, tell me: ====
* Year / make / model / engine
* Gas or diesel?
* When the code appears (cold start, highway, hard acceleration)

I’ll narrow this down to the most likely single cause for your vehicle instead of generic advice.