Powertrain, generic (extended)

P22FF SCR NOx Catalyst Inlet Temperature Too Low

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

Diesel engines raise exhaust temperature on purpose so the SCR catalyst can reduce NOx; this code reports that the gas entering the SCR stays too cold despite that. Ford describes it for the 6.7L and 3.2L diesels under its monitoring of the exhaust temperature controller: the measured SCR inlet value is compared with the setpoint, and the fault sets when it lags more than 80 °C behind for 300 s (2015 model year, roughly 800-1600 rpm and 50-600 Nm, EGT and EGR inputs fault-free). Deutz EMR5 maps P22FF to SPN 4360 FMI 1, below the normal range. Volvo cut false P22FF settings with a 2021 engine software update (KC-589). P05EB covers cold starts, P214A the opposite case.

Likely causes

Long idling or light-load operation keeps exhaust cold
Exhaust leak ahead of the SCR cools the gas or skews the reading
Exhaust temperature sensor reading too low while still in range
Engine software with overly strict monitor (update available on some makes)

Symptoms

  • Check engine light on
  • Reduced NOx conversion, possible further SCR efficiency codes
  • Code returns after extended idling

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–600
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

scr inlet temperature sensorscr catalystexhaust heat management

Related codes

P05EBP214AP20EEP2080P2084P249C

References: fordservicecontent.com, fordservicecontent.com, serdia.deutz.com, static.nhtsa.gov.