P0253: Injection pump fuel metering control A low (cam/rotor/injector), diesel
Injection pump fuel metering control A low
Severity: Severity not verified — if the car runs badly, have it inspected
The sources read define the code and its causes but do not say how urgent it is, so no urgency class is claimed. Get it checked, more so if the engine will not start or loses power.
P0253 in short
P0253 is a diesel-only code: the computer sees a mismatch between the signal sent to the injection pump's fuel control actuator and the signal returned by the metering sensor. Wiring and connector faults, a clogged fuel filter or a failing pump are the listed causes. Get it checked.
The computer commands an actuator on the injection pump and reads a metering sensor to see the result.
P0253 sets when the voltage between those two signals varies from what it expects, and the circuit reads low. TroubleCodes.net says circuit codes often come from poor connections and corrosion rather than failed parts.
Most likely causes
These are general causes for this code across vehicles. None is specific to one make or model.
Cause 1: Damaged or corroded wiring or connectors
Common general cause- Why it ranks here
- Both sources and the TroubleCodes.net page put wiring and connector faults first; circuit codes often come from poor connections rather than parts.
- What would change this
- Rises if a damaged or corroded connector is found. Falls if wiring and connectors test clean.
Cause 2: Clogged fuel filter, contaminated fuel or a failing pump or lift pump
Common general cause- Why it ranks here
- TroubleCodes.net lists clogged filters, water or bacterial growth in the fuel, and failed pumps among the causes.
- What would change this
- Rises if the filter is clogged or the fuel is contaminated. Falls if the supply tests fine.
Cause 3: Faulty fuel control actuator, fuel quantity actuator or position sensor
Common general cause- Why it ranks here
- TroubleCodes.net lists the fuel control actuator and the metering sensor as the parts that must agree.
- What would change this
- Rises if the actuator and sensor signals disagree. Falls if they match.
Cause 4: Engine computer fault (rare)
Common general cause- Why it ranks here
- TroubleCodes.net lists the computer as a rare cause to check only after other causes.
- What would change this
- Rises only after wiring, actuator and sensor all test good.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Look over the wiring and connectors at the injection pump and its fuel control actuator and sensor for damage, corrosion or a loose plug.
IfDamaged, corroded or loose wiring or a connector is found
It meansThe circuit fault is the likely cause.
IfWiring looks fine
It meansHave the actuator and sensor signals tested.
Step 2: Have a shop compare the signal sent to the fuel control actuator with the signal returned by the metering sensor, using a bidirectional scan tool.
Warning:The injection pump is on a high-pressure diesel fuel system, and fuel can spray at high pressure if a line or fitting is opened. Leave pump work to a diesel shop.
IfThe two signals do not agree
It meansThe actuator, sensor or pump is suspect.
Points to: Clogged fuel filter, contaminated fuel or a failing pump or lift pump
IfThe signals agree and the code returns
It meansA fault in the computer is possible but rare; recheck everything else first.
Symptoms
- Hard starting or no start
- Heavy smoke from the tailpipe
- Rough idle
- Weak acceleration, hesitation or loss of power
- Worse fuel economy
How to fix
Step 1: With the engine off and cool, look at the visible wiring and plugs near the injection pump for chafing, corrosion or a loose connector.
On your vehicle
We don't have reviewed vehicle-specific evidence for P0253 yet. The causes and tests above apply across vehicles.
Related codes
Sources and review
- On-Board Diagnostic Trouble Codes (generic code title list)
- P0253 trouble code: injection pump A, rotor/cam, fuel metering control A low
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error