Powertrain, generic · Auxiliary emission controls

P04F1 EVAP System Purge Line Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P04F1 is the function check of a purge line that is not the high-load path A – by the wording of another code list the low-pressure path to the intake manifold, counterpart of P04F0. The purge valve opens and the tank pressure or mixture reaction is missing or wrong: the line is blocked or off, or a check valve sticks. CARB requires every purge path to be checked; a FCA patent describes such a stepwise test. No manufacturer document available to us names this code.

Likely causes

Purge line to the intake manifold off, kinked or blocked
Check valve in the low-load path sticking
Purge valve not opening fully
Tank pressure sensor misreading

Symptoms

  • Check engine light on
  • Possibly fuel smell
  • No change in driving

Repair estimate

DifficultyEasyDIY possible
Parts and labour€30–250
Time0.3–1.5 h

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

Parts involved

purge linepurge check valveevap purge valveengine control module

Related codes

P04F0P0441P0497P0496P04E0

References: law.cornell.edu, patents.google.com.