Diagnostic Overview
CAT fault code 102-17 generally means intake manifold pressure or boost pressure is below normal at a least-severe level. The engine may still run but could feel weak under load. Common causes include small charge-air leaks, intake restriction, exhaust leaks, or turbo response issues. If ignored, the condition may progress to stronger low-boost codes or derate.
Likely Causes
Small boost leak; loose CAC clamp; restricted air filter; exhaust leak before turbo; turbo actuator issue; faulty pressure sensor; sensor port restriction.
What To Check First
Inspect CAC boots and clamps, check air filter restriction, look for soot trails from exhaust leaks, and compare boost pressure under load.