P008A — Low Pressure Fuel System Pressure Too Low — 6.7 Powerstroke
Diagnostic reference for P008A on 6.7 Powerstroke (2011–present).
What it means
Low-side (supply) fuel pressure is below expected.1
Most likely causes
- Frame-mounted low-pressure fuel pump module performance degradation — The 6.7 Powerstroke low-pressure supply is provided by a frame-mounted pump module; reduced output or electrical supply issues can cause low supply pressure.1
- Clogged or restricted fuel filters — Restricted primary/secondary filtration increases suction demand and lowers measured low-side pressure.1
- Supply-line restriction or leak on the suction side — Kinks, collapsed hose, or air ingress on the supply line to the low-pressure pump reduces net pressure available to the high-pressure pump.1
- Fuel starvation from tank pickup or tank vent restriction — Restricted pickup screen or venting can mimic a pump fault by limiting fuel availability to the low-pressure module.1
How to diagnose
- Verify freeze-frame conditions and repeat the fault under controlled load.
- Monitor live low-side fuel pressure vs. commanded pressure during idle and acceleration.
- Inspect fuel filters for condition and service history; check for water/contamination.
- Inspect frame-mounted pump module electrical connections, power/ground, and relay operation.
- Perform a visual and physical check of supply lines from tank to low-pressure pump for kinks, damage, or air leaks.
- Check tank pickup screen and vent system for blockage.
- Compare symptoms to related fuel-pressure codes to isolate low-side vs high-side issues.
- P0087 indicates high-pressure rail pressure too low, often high-pressure pump or rail control related.
Parts and tools you may need
- Fuel pressure gauge capable of low-side diesel pressure
- Scan tool with live data for low-side fuel pressure and pump command
- Fuel filter set
- Basic hand tools for filter and line inspection
Tools you’ll need
- OBD-II scan tool — Reads P008A and live low-side fuel pressure vs commanded to confirm the supply pressure drop under load.
- digital multimeter — Checks frame-mounted low-pressure pump module power, ground, and relay voltage drop to rule out electrical supply issues.
- fuel pressure gauge — Measures actual low-side supply pressure at the pump outlet to verify pressure deficiency versus scan data.
- inspection mirror — Lets you see hidden supply lines, tank pickup screen, and vent routing for kinks, damage, or blockage.
Rough cost and difficulty
| Likely repair | Parts | Shop labor | Who usually does it |
|---|---|---|---|
| Fuel filter service | $30–$150 | 0.3–1 hrs | Easy DIY |
| Fuel supply or return line repair | $30–$200 | 0.5–2 hrs | DIY with tools and a manual |
| Lift pump / fuel transfer pump | $100–$400 | 1–3 hrs | DIY with tools and a manual |
Typical US independent-shop figures; labor runs about $120–$180 per hour (dealers charge more). Confirm the diagnosis before buying parts.
When to see a pro
If low-side pressure remains below specification after filter and line checks, have a qualified diesel technician test the frame-mounted pump module and supply circuit. High-pressure fuel system work requires specialized training and tools. Do not attempt high-pressure fuel repairs without proper certification.
Check for recalls
Recalls are tied to your truck’s VIN, so check yours directly: enter the VIN at NHTSA’s recall lookup. Open safety recalls are repaired free at a dealer.
Sources
Repair videos: P008A on the 6.7 Power Stroke
Third-party videos, not ours — picked for this engine. Confirm anything against the factory service information for your truck.
Spotted an error, or something missing? Tell us
Run a 6.7 Powerstroke? This goes straight to the editor — it is not published.