P208E
Reductant Injection Valve Stuck Closed (Bank 1 Unit 1)
The DEF injection valve at bank 1 unit 1 does not open when commanded — typically crystallised DEF blocks the nozzle, no flow into the SCR.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Common causes
Ordered by how often each turns out to be the cause.
- Nozzle crystallisedCommon
- Valve seizedPossible
- Carbon or debris buildup preventing free movementLess likely
Parts involved
- Reductant Injection Valve
P208E is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.