Need car parts? Select your vehicle
Reading Time: 3 minutes
Summary
  • If your vehicle logs a P0251 trouble code, it means that the PCM has detected an abnormality in the engine’s operating conditions based on the readings from the fuel rail pressure sensor.
  • A failed fuel control actuator, fuel rail pressure sensor circuit issues, and a faulty fuel pump are common issues that can trigger a P0251 code.
  • Decreased fuel economy and poor acceleration are common symptoms of the P0251 code.

The fuel injection system is controlled by the powertrain control module (PCM) which controls the operation of fuel injectors and other components based on information from various sensors.

P0251 is one of the several trouble codes related to a fault in this system. Know more about it through this article.

See also  A Short Course on Fuel Systems

What Does the P0251 Code Mean?

Diagnostic trouble code (DTC) P0251 stands for “Injection Pump Fuel Metering Control “A” (CAM/Rotor/Injector).” This code typically applies to vehicles with diesel engines.

The injection pump fuel metering control circuit “A” is usually located inside or on the side of the injection pump. It’s usually equipped with a fuel rail pressure (FRP) sensor and a fuel control actuator (FCA).

fuel rail pressure sensor monitors fuel delivered to engine
The FRP sensor monitors the amount of fuel delivered to the engine by the fuel FCA to the high-pressure pump and sends this data to the PCM using voltage signals.

The FRP sensor monitors the amount of fuel delivered to the engine by the fuel FCA to the high-pressure pump and sends this data to the PCM using voltage signals. The PCM then uses this data to analyze the amount of fuel it’ll inject into the engine based on engine operating conditions.

Code P0251 is set once the PCM detects an input signal that doesn’t match normal engine operating conditions. This “normal” condition is based on what’s set in the PCM’s memory.

Note: The definition of code P0251 might be different depending on the vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.

What are the Common Causes of the P0251 Code?

What are the Common Symptoms of the P0251 Code?

See also  How to Replace a Fuel Pump

How to Diagnose the P0251 Code

While DTC P0251 is a generic powertrain code, the steps for diagnosing this code will vary across different makes and models. If you don’t have the tools and technical know-how to diagnose the problem, it might be best to have a professional identify the problem for you instead. If you’re an experienced automotive DIYer, then you can go ahead and do it yourself.

How to Fix the P0251 Code

car owner explains issue to male mechanic
We recommend bringing your vehicle to the nearest auto repair shop and having a certified mechanic fix the issue.

Trying to fix any trouble code can be tricky, especially if you don’t have the right tools and technical knowledge. We recommend bringing your vehicle to the nearest auto repair shop and having a certified mechanic fix the issue.

But if you have the tools and experience for it, make sure to have the right tools before starting. Guides like those from Chilton can help you fix the issue correctly. An ALLDATA subscription containing vehicle-specific repair information will also be of great help.

About The Authors
Written By Automotive and Tech Writers

The CarParts.com Research Team is composed of experienced automotive and tech writers working with (ASE)-certified automobile technicians and automotive journalists to bring up-to-date, helpful information to car owners in the US. Guided by CarParts.com's thorough editorial process, our team strives to produce guides and resources DIYers and casual car owners can trust.

Reviewed By Contact Center Manager and Technical Reviewer at CarParts.com

William “Bill” Guzenski has produced hundreds of how-to videos for the automotive community. He’s an ASE Certified Master Automobile Technician, and is affiliated with the Specialty Equipment Market Association (SEMA). He loves attending race events and car shows throughout the country, as well as traveling in his 40-foot motorhome, exploring abandoned mines and ghost towns.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

get 10% off everything
Subscribe
Notify of
guest
0 Comments
Inline Feedbacks
View all comments

View all Questions & Answers

expand_more
CarParts.com Answers BE PART OF OUR COMMUNITY: Share your knowledge & help fellow drivers Join Now