تفحم بخاخ معالجة العادم

The exhaust-side fuel injector's tip fouled with carbon, so its spray is distorted or restricted. It sits in the exhaust with combustion products flowing past it, and it only operates during regeneration — so it spends most of its life being baked without being cleaned by its own flow.

A coked injector delivers too little or sprays unevenly, so regeneration temperatures are not reached and the filter never clears. The module reports its performance rather than its condition. Distinguish it from a leaking one, which is the opposite failure and raises temperatures rather than failing to. Inspect the tip on removal, and be aware a new injector into an exhaust that coked the last one will coke too unless what produced the excess soot is found.