Powertrain, generic (extended)

P2493 EGR Cooler Bypass Position Sensor Range/Performance (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2493 is a plausibility fault: the bank 1 bypass position signal stays inside its electrical limits, but its value or behaviour does not fit the commanded flap position or the learned end stops. GM names the code in preliminary bulletin PI1449 for the 2015 Silverado and Sierra with the LML Duramax, where it showed up together with P2495, P24C4 and P06A3. The fix there was a complete new bypass valve, since the sensor sits in the valve and must not be taken apart. Range errors often come from a worn sensor track, a shaft that turns without the sensor following, or deposits that shift the end positions. The pure circuit faults are P2492, P2494 and P2495; bank 2 reports P2498.

Likely causes

Worn or defective bypass valve with integrated sensor
Deposits shifting the learned end positions
Unstable 5 V reference shared with other sensors

Symptoms

  • Check engine light on, often with further bypass codes
  • Bypass position in the live data does not match the command

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€150–900
Time1–4 h

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

Parts involved

egr cooler bypass position sensor b1

Related codes

P2492P2494P2495P2498P24C4P06A3

References: static.nhtsa.gov, gsi.ext.gm.com, law.cornell.edu.