P0087 means the engine control module measured fuel rail pressure below the commanded value by more than the allowed margin, for long enough to count. P0088 is the opposite. Unlike the sensor and regulator circuit codes around it (P0190 through P0194, P0090 through P0092), P0087 reports a value: the module trusted its sensor and the pressure was low.
Severity: moderate to high. Can you keep driving? Not far. Low rail pressure produces hesitation, lack of power, misfires and stalling under load, and on a diesel the module cuts fueling to protect the injectors. Drive to a shop if it runs cleanly; tow it if it stalls.
The three places the pressure went
1. It never arrived from the tank. The high-pressure pump can only raise what the low-pressure pump delivers. Kia's bulletin PS476 (March 2017, revised 2018) for the 2014 to 2016 Soul, 2015 to 2016 Forte with GDI and 2014 to 2015 Sorento traces intermittent hesitation and P0087 to a restricted low-pressure fuel line, and gives the test: measure pressure at the low-pressure pump's output line in the tank and compare it with a table by engine, roughly 70 to 72 psi for those engines. Pressure good at the tank but low at the engine means the line between them.
2. The high-pressure pump could not raise it. Kia's bulletin FUE 026 (September 2013) for the 2011 to 2013 Optima and Sportage GDI, 2012 to 2014 Sorento and 2014 Cadenza GDI covers P0087 with a procedure that ends, if needed, in replacing the high-pressure fuel pump, the fuel delivery pipe and the mounting bolts, with a separate bulletin on handling GDI high-pressure hardware and the one-time-use fasteners. A worn pump, a stuck regulator on it, or a worn cam lobe that drives it, all leave the rail short.
3. The fuel boiled. Audi's product support bulletin 2033211/1 (March 2013) for the 2013 A4, allroad, A5, Q5 and A6 with the 2.0 TFSI: under extreme conditions such as long idling or extended stop-and-go, heat builds in the rail, vapor bubbles form in the fuel and pressure drops temporarily, setting P0087. The freeze frame shows coolant above 102 °C. Audi's instruction was not to replace anything and to advise the customer that running the A/C reduces it, while a cooling strategy update was developed. A code with nothing broken.
Causes, in the order they are found
Low fuel level or a weak low-pressure pump · a restricted line or filter · a high-pressure pump or its regulator · a leaking injector or a rail leak · hot-fuel vapor under specific conditions · a rail pressure sensor reading low (usually with P0192) · the module, last.
A diagnostic order
- Record the freeze frame. Coolant temperature, engine load and speed at the fault separate a hot-idle vapor case from a load-related supply case.
- Check the fuel level and listen for the low-pressure pump.
- Measure low-side pressure at the tank and at the engine against the specification; Kia's table for its GDI engines is about 70 to 72 psi at the pump output.
- Watch commanded and actual rail pressure on the scan tool at idle, at 2,500 rpm and under load. Pressure that tracks at idle and collapses under load is supply or pump; pressure that never reaches target is the pump or a leak.
- Check the regulator circuit (P0090 family) and the sensor (P0192) if their codes are present.
- Replace the high-pressure pump only after the low side has passed, with the manufacturer's one-time-use hardware, then clear and verify under load.
Frequently asked questions
Can I drive with a P0087 code?
Only carefully and not far. Low rail pressure leans the engine under load and can stall it, and on a diesel the module cuts fueling. Have it towed if it stalls.
Is P0087 the high-pressure fuel pump?
Sometimes, as in Kia's 2011 to 2014 GDI bulletin, but the low-pressure side comes first: a restricted line or a weak in-tank pump starves the high-pressure pump and sets the same code. Measure low-side pressure at the tank before replacing the high-pressure pump.
Can P0087 set with nothing wrong?
Yes. Audi documented it on 2013 2.0 TFSI engines: long idling in heat let fuel vapor form in the rail and pressure dip, and the instruction was not to replace parts. The freeze frame showing coolant above 102 °C at idle is the signature.
How much does it cost to fix P0087?
A fuel filter or a restricted line is a modest job. An in-tank pump is a moderate part with tank access labor. A high-pressure pump is a major part, with one-time fasteners and specific handling on GDI engines.
Related codes
- P0088: fuel rail pressure too high.
- P008A: low pressure fuel system pressure too low; see P008A.
- P0090 to P0092: fuel pressure regulator control circuit; see P0090.
- P0191 to P0194: rail pressure sensor; see P0192 and P0194.
The code number itself tells you the family and the domain; how to read an OBD2 code number explains what each character means.