Diesel Trouble Codes

Low Oil Pressure Warning — International DT466E

A low oil pressure warning on a 1996–2003 International DT466E can be real low oil pressure or a sensor-circuit fault. The ECM can warn, derate or shut down…

Updated October 15, 2026

What’s going on

On this HEUI engine the oil pressure warning reflects the engine oil pressure (EOP) sensor signal and the ECM’s engine-protection strategy. A low oil pressure warning can be real low oil pressure (DTC 313/314) or a sensor-circuit fault (DTC 211/212). Check oil level and verify pressure with a mechanical gauge before replacing the sensor; the engine may be programmed to derate or shut down.1

Most likely causes

  1. Real low engine oil pressure (DTC 313/314) — Engine oil pressure has dropped below the warning or critical level. Treat as real until proven otherwise: check oil level and actual oil pressure with a mechanical gauge before blaming the sensor. DTC 313 is Engine Oil Pressure Below Warning Level; DTC 314 is Engine Oil Pressure Below Critical Level.231
  2. Engine oil pressure sensor signal out of range low (DTC 211) — EOP sensor signal voltage is below its valid range. Usually an open 5 V reference, an open signal circuit or a failed EOP sensor: a sensor-circuit fault, not necessarily real low oil pressure.4
  3. Engine oil pressure sensor signal out of range high (DTC 212) — EOP sensor signal voltage is above its valid range. Usually a failed EOP sensor or a signal circuit shorted to voltage.5

How to narrow it down

  1. Read stored Navistar three-digit DTCs with a scan tool or by counting amber engine lamp flashes; DTC 111 means no faults.
  2. If DTC 313 or 314 is present, stop the engine if pressure is critically low. Verify oil level, oil condition and actual oil pressure with a mechanical gauge before replacing the sensor; the engine may be programmed to shut down.
  3. If DTC 211 or 212 is present, inspect the EOP sensor connector and wiring for opens, shorts to voltage or ground, and check the 5 V reference and signal circuits. Compare sensor voltage to spec and test or replace the EOP sensor if the circuit checks good.
  4. With the engine running at idle and at speed, compare mechanical gauge pressure to ECM-reported pressure. A mismatch points to a sensor or circuit issue; a confirmed low reading points to real oil pressure loss.

Parts and tools you may need

Tools you’ll need

Rough cost and difficulty

Likely repairPartsShop laborWho usually does it
Temperature or pressure sensor (coolant, intake air, oil, fuel temp)$30–$1500.3–1.5 hrsEasy DIY
Low oil pressure repair (pickup tube, pump or regulator)$100–$8004–12 hrsShop

Typical US independent-shop figures; labor runs about $140–$200 per hour (dealers charge more). Confirm the diagnosis before buying parts.

When to see a pro

If DTC 314 is set or a mechanical gauge confirms critically low oil pressure, stop the engine and have it inspected immediately to avoid bearing damage. If the warning persists after sensor/circuit checks, professional diagnosis of the lubrication system is needed.

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

  1. Curated symptom seed — International DT466E (curated) ↩︎ ↩︎

  2. Curated DTC seed — International DT466E (curated) ↩︎

  3. Curated DTC seed — International DT466E (curated) ↩︎

  4. Curated DTC seed — International DT466E (curated) ↩︎

  5. Curated DTC seed — International DT466E (curated) ↩︎