Controller displays E026 and indicates boost pressure low

Safety: Allow the turbocharger to cool before touching. Hot surfaces can cause burns.

• Air filter check: Inspect and replace a clogged air filter element (see E015).
• Inspect boost hoses: Check all charge‑air hoses and clamps between turbo, intercooler, and intake manifold for splits, loose clamps, or oil‑soaked rubber. Tighten or replace as needed.
• Intercooler inspection: Look for damage or leaks in the intercooler core. Oil staining may indicate a leak.
• Turbocharger condition: With engine off and cool, remove the intake hose and gently check the turbo shaft for excessive play or binding. Any scraping or heavy play indicates a failing turbo that should be replaced.
• Boost sensor test: Compare controller boost reading with a mechanical gauge if available. Replace the boost pressure sensor if it reads low despite normal mechanical boost.