حساس فرق ضغط غاز العادم معيب

The sensor that reads the pressure drop across the particulate filter — the filter's fuel gauge, since soot load is inferred from how hard the exhaust pushes to get through. Every regeneration is scheduled from this number, which is what makes its failures consequential out of proportion to its price: a sensor lying low teaches the module the filter is empty, so regenerations stop and the filter fills toward the forced-regeneration ladder; lying high burns fuel on regenerations nothing needed.

Its plumbing fails more than it does. Two thin hoses tap the exhaust either side of the filter, and they crack with heat, block with soot, and get refitted swapped after exhaust work — each producing believable wrong readings the sensor faithfully reports. The free cross-checks: zero difference with the engine off, small and steady at warm idle, climbing with load. A reading that ignores the engine has convicted the plumbing, not the sensor — and either is a fraction of the filter this family protects.