Powertrain, generic (extended)

P2433 AIR System Air Flow/Pressure Sensor Circuit High (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

With P2433 the bank 1 secondary air pressure signal sits above its upper limit, pointing to a signal wire shorted to the 5 V reference or to battery voltage, an open sensor ground or a failed sensor. GM uses more than 95 % of the reference on the 2005–2006 3.8L V6, more than 94 % on the 2006 Corvette and CTS-V V8s and in the 2018 tables (800 of 1,000 samples), always as a Type B fault watched without a break. Volkswagen's 2014 data put the threshold above 4.65 V (Beetle, Golf CBFA) or above 4.5 V (2.5L engine). A broken ground often shared with other sensors can make them report at the same moment, which helps narrow the search. P2432 is the low-side partner, P2438 the bank 2 version.

Likely causes

Signal wire shorted to 5 V reference or battery voltage
Open sensor ground or corroded ground terminal
Pressure sensor failed internally

Symptoms

  • Check engine lamp after two trips
  • Secondary air readiness stays incomplete

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–300
Time0.5–2 h

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

Parts involved

air system flow sensor b1sai wiring

Related codes

P2430P2432P2438

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov.