Diesel Trouble Codes

P0299 — Turbocharger/Supercharger Underboost Condition — 6.0 Power Stroke

Diagnostic reference for 6.0L Power Stroke (2003.5–2007) P0299.

Updated October 15, 2026

What it means

Generic definition: Boost pressure is below the minimum expected for current conditions. On the 6.0L Power Stroke this is commonly soot-stuck VGT vanes/unison ring, a faulty VGT control solenoid, a boost leak at intake/CAC boots, or a bad EBP signal confusing VGT control.1

Most likely causes

  1. Soot-stuck VGT vanes / unison ring causing underboost — Variable-geometry Garrett VGT can stick from soot, reducing boost output. Typical on this platform for underboost.1
  2. Faulty VGT control solenoid — VGT control solenoid malfunction can prevent proper vane positioning, leading to underboost. Typical on this platform.1
  3. Boost leak at intake/CAC boots or connections — Leaks in the intake/CAC boots reduce measured boost.1
  4. Bad EBP signal confusing VGT control — EBP sensor/tube faults affect VGT control; EBP feeds VGT control on the 6.0L.1
  5. MAP sensor or sensing hose/port soot plugging — MAP sensing hose/port can plug with soot, affecting boost feedback. MAP issues are relevant to boost diagnostics on this platform.2
  6. EBP sensor tube clogged with soot causing incorrect VGT control — EBP sensor reads exhaust manifold pressure through a steel tube; soot clogging is common and can upset VGT control.3
  7. EBP sensor circuit fault — EBP sensor circuit fault can corrupt VGT control input.4

How to diagnose

  1. Verify code P0299 is present and check for accompanying codes such as EGR or boost sensor faults that may indicate related issues.
  2. Inspect intake/CAC boots and connections for leaks that would reduce boost.
  3. Check MAP sensor and its sensing hose/port for soot plugging or splits before condemning turbo.
  4. Inspect EBP sensor tube for soot clogging; compare EBP reading to barometric pressure key-on engine-off.
  5. Evaluate VGT actuator response and VGT control solenoid operation; consider soot-stuck vanes/unison ring as a common cause.
  6. Review service history for repeated P0299 with part replacement without root cause resolution.

Common mistake to avoid

Replacing the turbo before smoke-testing the intake. Boost leaks at intercooler boots, end tanks and clamps are a common cause of low power and underboost codes, and they mimic a failing turbo. Source: BD Diesel — 6.7L Power Stroke problems and real fixes.

Parts and tools you may need

Tools you’ll need

Rough cost and difficulty

Likely repairPartsShop laborWho usually does it
MAP/boost pressure sensor$40–$2000.3–1 hrsEasy DIY
Exhaust backpressure sensor$60–$2000.5–1.5 hrsEasy DIY
Intercooler boot, clamp or pipe repair$20–$2000.5–2 hrsEasy DIY
VGT actuator / vane control solenoid$100–$4000.5–2 hrsDIY 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 diagnosis indicates internal turbo/VGT mechanical sticking or requires removal of injectors or high-pressure oil components, have a qualified diesel technician perform inspection. Repeated stalling or limp mode events should be evaluated promptly.

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 DTC seed — 6.0 Power Stroke (curated) ↩︎ ↩︎ ↩︎ ↩︎ ↩︎

  2. Curated DTC seed — 6.0 Power Stroke (curated) ↩︎

  3. Curated DTC seed — 6.0 Power Stroke (curated) ↩︎

  4. Curated DTC seed — 6.0 Power Stroke (curated) ↩︎