Powertrain, generic · Auxiliary emission controls

P0443 EVAP System Purge Control Valve A Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

The evaporative emission (EVAP) system stores fuel vapour from the tank in a charcoal canister; a purge valve lets the engine draw it off, and a vent valve opens the canister to fresh air. P0443 is the electrical check of purge valve A, which the module switches to ground in pulses; it compares the driver's feedback voltage with the commanded state. GM uses it for an open circuit (200 kΩ or more, 20 of 25 samples, MIL after two trips) and reports shorts as P0458/P0459; Ford covers open and short in P0443 (5 s). Purging then stops, the canister is no longer regenerated, and the leak and purge monitors are suspended.

Likely causes

Purge valve connector corroded, loose or off
Purge valve coil open or shorted
Control wire broken or chafed, or supply missing (fuse, main relay)
Driver in the engine module

Symptoms

  • Check engine light on
  • Possibly fuel smell (no purging)
  • EVAP leak test does not run

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.

What to check first

  1. Measure valve resistance
  2. Inspect connector

Parts involved

evap purge valvepurge valve wiringengine control module

Related codes

P0444P0445P0458P0459P0441P0449

References: gsi.ext.gm.com, gsi.ext.gm.com, fordservicecontent.com, saabwisonline.com.