Code Details
| Display code | SPN 94 FMI 1 |
|---|---|
| SPN | 94 |
| FMI | 1 |
| OEM code | None listed |
| Manufacturer | Volvo |
| System | Engine �?fuel system |
| Component | Fuel lift pump / fuel filter / fuel supply circuit |
| Source address | Unknown or not applicable |
| Severity | high |
| Review status | source backed |
| Source confidence | medium |
| Last reviewed | 2026-06-12 |
Plain-English Meaning
The Volvo D13 uses a low-pressure lift pump to supply fuel to the high-pressure injection pump at a controlled pressure. SPN 94 FMI 1 indicates the supply pressure is too low. On Volvo VNL, VNX, and VHD trucks equipped with the D13, this usually means the fuel filter needs replacement, the lift pump is weak, or there is an air leak in the supply side of the fuel system. Low fuel delivery pressure prevents adequate rail pressure and causes power loss.
SPN 94 FMI 1 is Fuel Delivery Pressure below normal. On Volvo D13 with EMS3 engine management, VCADS Pro displays fuel delivery pressure as a live parameter. VCADS Pro can also run a fuel pressure test that cycles the lift pump and measures pressure response �?this distinguishes a filter restriction from a pump performance issue.
Common Symptoms
- Reduced power, especially at high load
- Hard start or extended cranking
- Engine stumble or surging under acceleration
- SPN 157 FMI 18 (low rail pressure) may appear concurrently
Possible Causes
Possible causes may include the items below. The list is not a parts diagnosis.
- Clogged primary or secondary fuel filter
- Lift pump wear or failure
- Air in the fuel supply system (low tank level, leaking supply fitting)
- Restricted fuel supply line
- Fuel delivery pressure sensor fault
First Checks
- Replace the fuel filter per Volvo D13 maintenance schedule �?this resolves the majority of SPN 94 FMI 1 cases
- Connect VCADS Pro and run the fuel pressure diagnostic to confirm delivery pressure under load
- Check for air ingestion: inspect supply line fittings and confirm adequate fuel level
- Inspect fuel supply lines for damage or restriction
- If pressure is still low after filter replacement, measure lift pump output pressure directly
Can I Keep Driving?
Reduced power likely. Continued operation with low fuel delivery pressure risks HP pump and injector damage.
Related Codes
Related Lookup Pages
Sources
- Volvo Trucks Tech Info Public Resources Volvo Trucks North America · oem · accessed 2026-06-11 · confidence medium
Source: Volvo Trucks North America, Volvo Trucks Tech Info Public Resources. This page paraphrases factual fields only and is not a substitute for the original document.
Open source - Volvo Trucks / Mack Trucks Technical Support Volvo Trucks North America / Mack Trucks Inc. · oem · accessed 2026-06-10 · confidence medium
Source: Volvo Trucks North America / Mack Trucks Inc., Volvo Trucks / Mack Trucks Technical Support. This page paraphrases factual fields only and is not a substitute for the original document.
Open source - SAE J1939 Standards Collection SAE International · official · accessed 2026-05-05 · confidence medium
Source: SAE International, SAE J1939 Standards Collection. This page paraphrases factual fields only and is not a substitute for the original document.
Open source
FAQ
Does the Volvo D13 use a gear-driven or electric lift pump?
The Volvo D13 uses a gear-driven mechanical lift pump integrated with the engine. This differs from some other platforms that use an electric in-tank or frame-mounted lift pump. A gear-driven pump will typically degrade gradually rather than fail suddenly, so monitoring fuel delivery pressure trend over time with VCADS Pro can help predict pump end-of-life before a hard failure occurs.
Can cold weather cause SPN 94 FMI 1 on the Volvo D13?
Yes. In cold weather, fuel wax formation can partially block filters or fuel lines, reducing delivery pressure. If SPN 94 FMI 1 appears only in cold conditions and clears when the fuel warms, a cold-weather fuel or filter condition is the likely cause. Using winter-grade diesel or adding anti-gel treatment as appropriate for the operating region prevents cold-weather fuel delivery problems.
Is VCADS Pro required to diagnose SPN 94 FMI 1 on the Volvo D13, or will a generic J1939 scanner work?
A generic J1939 scanner can read the SPN 94 FMI 1 code, but VCADS Pro provides the live fuel delivery pressure reading and the fuel pressure diagnostic test needed to distinguish a filter restriction from a pump failure. For anything beyond reading the stored code, VCADS Pro is recommended for D13 fuel system diagnosis.