John Deere Engines SPN652FMI7 Fault Code: Injector #2 Not Responding
Also called Cylinder #2 EI Fuel Delivery Failure
Injector #2 Not Responding · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
SPN 652 FMI 7 means the ECU does not see a drop in fuel rail pressure when cylinder #2's electronic injector (EI) fires. The engine will misfire and run rough on that cylinder because injector #2 is not delivering fuel. Alarm level is listed as Warning.
Medium severity. This is flagged as a Warning-level code, not an immediate shutdown fault. The engine keeps running but will misfire on cylinder #2, which can cause rough running, power loss, and long-term wear if ignored. Diagnose it within the shift rather than continuing to run the machine hard.
What does John Deere Engines error code SPN652FMI7 mean?
SPN 652 FMI 7 is set by John Deere's ECU when it monitors fuel rail pressure during the injection event for cylinder #2 and does not see the expected pressure drop. On the 8.1 L engine, six electronic injectors (EIs) are mounted in the cylinder head under the valve cover, spraying directly into the center of each cylinder bore. Each EI is fed high pressure fuel from a common rail, and the ECU controls injection timing and fuel amount by energizing a Two-Way Valve (TWV) inside the EI, which opens and closes the EI's spill valve.
Power to the EIs is supplied in two groups: cylinders 1, 2, and 3 share one common power wire, and cylinders 4, 5, and 6 share another. The ECU actually controls each injector individually by opening and closing that injector's ground circuit. So when this code sets, the ECU has determined that turning on EI #2's ground circuit is not producing the fuel rail pressure drop it expects, meaning fuel is not actually being delivered to cylinder #2.
If this code sets, the practical result is that the engine will miss or run rough at cylinder #2 because that cylinder is not getting fuel from its injector.
What triggers a John Deere Engines SPN652FMI7 code?
The code sets when the ECU does not detect a drop in fuel rail pressure at the moment fuel should be injected into cylinder #2. This check runs whenever the ignition is on and the fault condition is active. No specific pressure, voltage, or time threshold is given.
Common causes of SPN652FMI7
- Bad terminals or connector at the ECU
- Bad terminals or connector at the EI (injector) harness connector, located at the side of the cylinder head
- Restricted fuel line between the high pressure common rail (HPCR) and the inlet to the #2 EI, or a leaking, pinched, bent, or cracked fuel supply line
- Bad flow limiter
- Bad fuel line fitting at the #2 EI
- Bad fuel inlet connector at the #2 EI
- Loose retaining nuts at the #2 EI
- Bad #2 EI or bad #2 injector, including a dirty injector
- Failed cylinder cutout test, failed cylinder misfire test, or failed injector fuel leak off test result pointing at cylinder #2
- Incorrect high pressure pump timing
- Bad ECU software
- Bad ECU
How to troubleshoot John Deere Engines SPN652FMI7: first checks
- Visually inspect the ECU connectors for contamination, damage, or poor seating.
- Visually inspect the injector harness connector at the side of the cylinder head for contamination, damage, or poor positioning.
- Check all wiring between the ECU and the #2 injector for chafing, corrosion, or damage.
- Inspect the fuel line between the high pressure common rail and the #2 injector inlet for leaks, pinching, bending, or cracks, and confirm the fuel line fitting and inlet connector at the #2 EI are tight and undamaged.
- Check that the retaining nuts on the #2 EI are torqued and not loose.
- Run any available cylinder cutout test, cylinder misfire test, or injector fuel leak off test to confirm the #2 injector is the actual failure point.
- Confirm high pressure pump timing is correct if injector and fuel line checks come back clean.
- If all mechanical and wiring checks pass, consider ECU software or a bad ECU as the remaining cause.
How the code clears
No separate clearing step is listed. The code is active whenever the ignition is on and the ECU still detects the missing pressure drop at cylinder #2's injection event. Once the root cause (wiring, fuel line, injector, or ECU) is repaired and the rail pressure drop is detected normally on cylinder #2's injection event, the code should stop being active. Always verify the repair by clearing codes and confirming the fault does not return under normal operation.
Frequently asked questions
What does SPN 652 FMI 7 mean on a John Deere engine?
It means the ECU expected to see fuel rail pressure drop when cylinder #2's electronic injector fired, but it did not see that drop. In plain terms, injector #2 does not appear to be delivering fuel, so the ECU logs a fuel delivery failure for that cylinder.
Can I keep driving or working with this code active?
The alarm level is listed as Warning, not a shutdown code, so the engine will keep running. However, expect the engine to misfire and run rough on cylinder #2. Running it for extended periods with one cylinder not firing can cause uneven wear and reduced performance, so it should be diagnosed within the shift.
What are the most common causes of this code?
Causes range from connector and wiring problems at the ECU or injector harness, to fuel delivery restrictions like a pinched, bent, cracked, or leaking fuel line to the #2 injector, to a bad flow limiter, loose injector retaining nuts, a bad #2 injector itself, incorrect high pressure pump timing, or ECU software or hardware issues.
Where is the injector harness connector located?
It is located at the side of the cylinder head. Inspect it for contamination, damage, or poor positioning as a first step.
Is this a wiring issue or a fuel issue?
It can be either. The listed causes include both bad terminals or connectors at the ECU and injector harness, and mechanical fuel delivery problems like restricted or damaged fuel lines, bad fittings, or a bad injector. A leak off test or cylinder cutout test helps narrow down whether it's electrical or mechanical.
Does this code mean I need a new injector?
Not necessarily. A bad #2 injector (EI) is one listed possible cause, but connector corrosion, wiring damage, a restricted or leaking fuel line, a bad flow limiter, or loose retaining nuts on the injector can all cause the same symptom. Rule out wiring and fuel line issues before replacing the injector.
How is fuel delivered to each cylinder on this engine?
The 8.1 L engine uses six electronic injectors (EIs), one per cylinder, mounted in the cylinder head under the valve cover so they spray directly into the center of each cylinder bore. Each injector gets high pressure fuel from a common rail, and the ECU controls injection by switching a Two-Way Valve inside the injector, which opens and closes that injector's ground circuit individually.