2013–2024 RAM 2500/3500 6.7 Cummins Low-Pressure Fuel Supply Path
On 2013–2024 RAM 6.7 Cummins, verify lift pump voltage and supply pressure, filters, and aeration before any high-pressure component diagnosis.
Fault Overview
YMM-specific path for lift pump, filter, WIF, and aeration issues on RAM trucks with the 6.7 Cummins.
Engine & Platform Coverage
Symptoms
- •RAM 6.7 lift pump fault
- •Cummins fuel filter restriction
- •RAM water in fuel code
- •6.7 hard start supply
- •RAM fuel aeration
- •Cummins low pressure pump code
Possible Causes
- 1.Lift pump failure or voltage drop
- 2.Plugged filters
- 3.WIF sensor or actual water
- 4.Aeration after filter changes
- 5.Tank pickup issues
- 6.Fuel heater faults in cold climates
Wiring & Circuit Notes
Lift pump power, ground, and enable circuits. WIF sensor connector at the filter housing. Check frame grounds and corrosion points common on these trucks.
DVOM Specs & Sensor Tests
Supply pressure per Cummins/RAM specification. Lift pump voltage under load. Filter differential. WIF sensor readings. Clear-line aeration check.
Diagnostic Flow — FSM Sequence
AI Diesel Tech enforces this evidence-gate sequence. Each gate must pass before advancing.
6 steps locked behind Technician Mode- 1Step 1 — Confirm Fuel Level and Drain WIF: Confirm fuel level and drain WIF if present. Verify fuel quality.
- 2Step 2 — Verify Lift Pump Operation, Voltage, and Voltage Drop: Verify lift pump operation with scan data. Measure voltage and voltage drop at the pump under load. Check frame grounds and corrosion points common on these trucks.
- 3Step 3 — Measure Supply Pressure: Measure supply pressure during crank, idle, and load per Cummins/RAM specification.
- 4Step 4 — Check Filter Restriction: Check filter restriction with differential pressure. Replace if restricted and retest.
- 5Step 5 — Perform Aeration Confirmation: Perform aeration confirmation if pressure fluctuates. Check for new leaks after any filter service.
- 6Step 6 — Test WIF and Heater Circuits: Test WIF and heater circuits if codes are present. Inspect WIF sensor connector at the filter housing.
- 7Step 7 — High-Pressure Diagnosis Only After Supply Proven: Proceed to high-pressure side only after supply is proven. This prevents unnecessary CP3 or injector work on RAM 6.7 fuel delivery complaints.
Unlock the full evidence-gated diagnostic sequence, DVOM test steps, and repair procedures in Technician Mode.
Full Diagnostic Access
Verification steps, preventative measures, severity guidance, and legacy comparison are available in Technician Mode.
Typical Repair Costs
Lift pump replacement or wiring repair $150–450; filter service $80–200; WIF sensor $40–120; suction leak repair $50–150. Total typical $100–550.
Start Diagnosing This Fault Now
AI Diesel Tech walks you through every evidence gate in the correct order. Choose the plan that fits your shop.
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Summary
Use the AI Diesel Tech diagnostic engine to run this code through a structured, evidence-gated sequence and get a confirmed root cause before any parts are replaced.