P2496 EGR Cooler Bypass Position Sensor Circuit Intermittent/Erratic (Bank 1)

P2496 targets a bank 1 bypass position signal that jumps, drops out briefly or changes faster than the flap can physically move, without staying outside the electrical limits long enough for P2494 or P2495. No manufacturer documents P2496 publicly; GM's Duramax tables, which do cover the same analog sensor, only list the low, high and learning checks. The fault pattern is typical of loose terminals, a wire that breaks inside its insulation when the engine rocks, moisture creeping into the connector or a worn contact track in the sensor. Because the signal looks fine most of the time, the code may come and go; wiggling the harness while watching live data is the most useful test. CARB treats such sensors as comprehensive components. Bank 2 uses P249B.

Likely causes

Symptoms

• Check engine light that comes and goes
• Bypass position value jumps in the live data

Repair estimate

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

Parts involved

Related codes

References: law.cornell.edu, gsi.ext.gm.com.