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P0087: Fuel Rail/System Pressure Too Low

Severe

Quick answer

P0087 means the fuel pressure the computer measures is lower than the pressure it commanded, beyond what it can correct. On port-injected engines that is a filter, a tired in-tank pump or a regulator; on direct-injection gas and diesel engines it can also be the high-pressure pump or a leaking injector. Expect power loss under load, long cranks and stalling. Check the cheap side before the expensive pump.

What it means

Modern fuel systems are closed loop: a pressure sensor on the fuel rail reports actual pressure, the computer compares it with a target that changes with load, and it trims pump duty, a control valve or a regulator to close the gap. P0087 sets when actual pressure stays below target by more than the allowed margin for more than a moment. On a port-injection engine the target is usually 40 to 65 psi. On gasoline direct injection the rail runs 500 to 3,000 psi from a cam-driven high-pressure pump fed by the in-tank pump. On common-rail diesels the rail runs 5,000 to more than 30,000 psi, and the code often points at something expensive.

The cause list runs from a restricted filter or fuel-sock, a low tank, a weak lift pump and a pinched or collapsing line, through a pressure regulator or a control valve that cannot hold, to leaking injectors that return too much fuel, and finally the high-pressure pump itself: a worn cam follower on some European engines, or a failed pump on certain diesels that fills the whole system with metal. Cold gelled diesel, water in the fuel and air pulled in on the suction side produce the same code without any part being broken.

The order matters more on P0087 than on almost any other code, because the expensive answer is real and the cheap answers are common. Live data showing commanded versus actual rail pressure, a low-side pressure gauge, a fresh filter and, on diesels, an injector return-flow test will tell you where the pressure is going before you spend on a pump.

P0087 symptoms: what you'll notice

  • Loss of power that gets worse the harder you push: fine at a cruise, then a flat spot, surging or a stumble when you accelerate hard, climb a grade or tow.
  • Long cranking, a no-start when hot or after sitting, or an engine that starts and stalls.
  • Rough idle and misfire codes (P0300 family) that appear under load, or a lean code (P0171) riding along on port-injected engines.
  • Reduced-power or limp mode on diesels, sometimes with white or black smoke, hard starting in the cold and a rattle or knock at load.
  • On direct-injection gasoline engines, spark knock or a metallic pinging under load as the injectors run out of pressure to atomize fuel.

Common causes

Ordered from most to least likely.

  1. 1.

    Restricted fuel filter or in-tank strainer

    The cheapest and most common cause, especially on diesels and on any vehicle with a forgotten filter interval or a tank that picked up debris. A filter that restricts under high demand sets P0087 only at load.

  2. 2.

    Weak or failing in-tank (lift) pump, or its wiring, relay or pump-control module

    A pump that meets pressure at idle but sags under demand, a dropping voltage feed, or a control module that limits duty. Common on high-mileage vehicles and after running the tank near empty repeatedly.

  3. 3.

    Low fuel level, sloshing, or a collapsed or pinched supply line

    A quarter tank on a hill or a hard corner uncovers the pickup; a rubber line collapsing on suction restricts flow only under demand. Both look like an intermittent P0087 that never shows up in the driveway.

  4. 4.

    Failing high-pressure pump on direct-injection gasoline and common-rail diesel engines

    Worn internals, a control valve that will not hold, or on some European gasoline engines a cam follower worn through so the pump loses its stroke. On certain diesels the pump’s failure sheds metal into the rail, injectors and lines.

  5. 5.

    Leaking injector or a rail pressure relief valve that opens early

    An injector that returns too much fuel to the tank, or a relief valve stuck partly open, bleeds off pressure the pump made. Diesel return-flow testing finds the injector; a relief valve that leaks shows as pressure that will not build with the engine off.

  6. 6.

    Fuel pressure regulator or fuel pressure sensor fault

    A regulator dumping to return, or a sensor that reads low, both produce P0087. A sensor fault usually comes with its own circuit codes (P0190 to P0194).

  7. 7.

    Fuel contamination, gelled diesel, water, or air on the suction side

    Winter diesel that gelled, water in the separator, or a loose fitting or cracked line pulling air into the low side. Nothing is broken; the fuel or the seal is. Check first in cold weather and after a suspect fill-up.

How to fix it: diagnosis, step by step

Cheapest and most likely checks first.

  1. 1 Read the freeze frame and watch commanded versus actual pressure

    Note the load and rpm when the code set. Then, in live data, graph commanded rail pressure against actual while you snap the throttle and, if safe, while a helper loads the engine. A gap that opens only at high demand points at supply (filter, lift pump, line, low fuel); a gap present at idle points at the high-pressure side, a leaking injector, or the regulator.

  2. 2 Check the easy things

    Fuel level and quality, the age of the filter, the water separator on diesels, and the supply line for kinks or a section of rubber that could collapse. Replace a filter of unknown age before any further testing; it is the single highest-yield step on this code.

  3. 3 Test the low-pressure side with a gauge

    On the test port or with an inline gauge, read supply pressure at idle and under a snap of the throttle, and check it against the specification. Low-pressure pumps that hold spec at idle but fall off under demand are the fault; so is a pump whose pressure drops as the tank empties. Watch the pump’s voltage while you test; a dropping feed is a wiring or control-module problem, not a pump.

  4. 4 Test pump current or duty cycle

    A current ramp or an amp-clamp reading on the pump feed shows a pump working too hard (restriction), too little (worn), or intermittently (brushes or wiring). On vehicles with a fuel pump control module, read the commanded duty on the scan tool; a module commanding full duty while pressure lags means the pump or its supply cannot deliver.

  5. 5 Isolate the high-pressure side on direct-injection and diesel engines

    With the low side proven, look at the high-pressure pump’s control valve command and the rail’s response, and inspect the pump’s drive: on gasoline engines with a cam-driven pump, pull the pump and inspect the follower and the cam lobe for wear. On diesels, run the injector return-flow test: one injector returning far more than the others is bleeding the rail down.

  6. 6 Check the pressure sensor and the relief valve

    Compare the rail pressure sensor’s key-on reading with what the system should show at rest and, where possible, with a mechanical gauge. A sensor that reads low condemns itself; a rail that will not hold pressure with the engine off points at a relief valve or an injector leaking down.

  7. 7 Repair what failed, and on a diesel pump failure, stop and inspect for metal

    Fit the filter, pump, regulator, injector or high-pressure pump the tests condemned, with genuine or OEM-supplier parts. If a diesel high-pressure pump has failed internally, inspect the fuel for metal before installing anything: a contaminated system needs the rail, injectors, lines and tank cleaned or replaced, or the new pump dies the same way. Clear the codes and confirm commanded and actual pressure track under a full-throttle test drive.

Known P0087 patterns by make

Brand-specific failure patterns from the field: find your make before parts-shopping.

Volkswagen / Audi 2005.5–2008 GTI, Jetta, Passat, A3, A4 with the 2.0T FSI (EA113) engine

The high-pressure pump on this engine is driven by a cam lobe through a small cup-shaped follower, and the follower wears through. Once it does, the pump loses stroke, P0087 sets under load, and the cam lobe itself gets chewed. Inspect the follower every 20,000 to 30,000 miles and replace it cheaply; a P0087 on one of these means pulling the pump and looking at the follower and the lobe before anything else.

Chevrolet / GMC Duramax and Ford Power Stroke 2011–2016 Duramax LML (Silverado/Sierra 2500/3500) and 2011 and newer 6.7L Power Stroke (F-250/F-350) with the Bosch CP4.2 pump

These trucks are the reason P0087 has a bad reputation. The CP4.2 high-pressure pump can fail without warning, and when it does the metal it sheds travels through the rail, lines and injectors. P0087 with P0088 or P0191 and a sudden loss of power is the classic presentation. Do not let anyone install just a pump: the fuel needs to be inspected for metal and the whole system evaluated, and the repair on a contaminated truck runs to five figures. Check for any extended coverage or settlement programs for your VIN.

Chevrolet 2011–2016 Cruze and 2012–2017 Sonic with the 1.4L turbo

P0087 on the 1.4T is usually the in-tank fuel pump module getting weak: the engine hesitates and loses power under boost, and the code sets on a hard pull. A low-side pressure test under load confirms it. The fix is the pump module, and the fuel filter is built into that module on these cars, so there is no separate filter to change first.

Parts & tools you may need

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Related codes

Frequently asked questions

What does code P0087 mean?
P0087 means the fuel pressure measured at the rail is below what the engine computer commanded, by more than it can correct. The fuel system cannot keep up with demand: a restricted filter, a weak pump, a leaking injector, a regulator, or a failing high-pressure pump. It is serious: the engine can lose power or stall under load, and on some diesels the cause is a pump that damages the whole system.
Can I drive with P0087?
Gently and briefly, to get it tested. The danger is losing power while merging, passing or climbing, or stalling in traffic. On a direct-injection or diesel engine, keep driving a pump that is failing and you risk turning a pump repair into a full fuel-system replacement. Get the commanded-versus-actual pressure read soon.
Is P0087 just a bad fuel pump?
Often it is the in-tank pump, but the filter, the strainer, a collapsed line, low fuel, a leaking injector, the regulator and the high-pressure pump all set the same code. The tests take an hour and the wrong pump costs hundreds. Read commanded versus actual pressure and put a gauge on the low side before you buy.
Why does it only happen when I accelerate hard or tow?
Because that is when the engine demands the most fuel. A restriction or a tired pump can meet the small demand of idle and cruising and only falls short when the injectors open wide. That pattern says supply side: filter, strainer, lift pump or a line, and on some vehicles a tank low enough to uncover the pickup.
What is the CP4 problem people mention with P0087?
Certain common-rail diesel trucks of the early 2010s use a Bosch CP4 high-pressure pump that can fail suddenly and send metal debris through the rail, injectors and lines. P0087 with P0088 or P0191 and a sudden power loss on one of those trucks is the signature. Do not simply install a new pump: the system has to be inspected and cleaned or replaced, which is why that repair costs many times more than a pump.
How much does it cost to fix P0087?
A fuel filter is $20 to $80 on a gasoline engine and $50 to $150 plus labor on a diesel. An in-tank pump module is $250 to $900 installed. A fuel pressure regulator or sensor is $60 to $250. A direct-injection high-pressure pump is $400 to $1,200 installed; a diesel high-pressure pump alone is $1,500 to $3,500, and a diesel pump failure that contaminates the system can reach $8,000 to $12,000. Injectors run $150 to $500 each on gasoline engines and more on diesels.
What is the difference between P0087, P0088 and P0090?
P0087 is rail pressure too low. P0088 is rail pressure too high, which points at a control valve, regulator or return restriction. P0090 is a circuit fault in the fuel pressure regulator or control valve itself, electrical rather than hydraulic. P0087 with P0088 alternating on a diesel is a sign the high-pressure pump’s control is failing, and on some trucks, that the pump is coming apart.
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