Powertrain, generic (extended)

P246F Exhaust Gas Temperature Sensor Circuit Range/Performance (Bank 1 Sensor 4)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P246F stands for a fourth bank 1 exhaust temperature probe whose signal is electrically fine but physically implausible. Both main users test it after a long soak. Ford's diesels compare it with three other probes after at least 6 h off and allow no more than 50 °C between them, which unmasks a probe stuck at one value. GM's 2025 diesel tables wait for more than 10,800 s engine-off, then compare how far the probe warms within a calibrated time against a temperature map; too little rise points to a probe that has slipped from the pipe, or to a frozen signal, rated Type B with the MIL in the second trip. Electrical faults of the probe are P2470 to P2472, while P246E covers the model comparison on Ford. A plausibility fault often follows a loose probe after exhaust work.

Likely causes

Probe stuck at one value or drifting
Probe loose or backed out of the exhaust pipe
Probe connectors swapped with a neighbouring sensor

Symptoms

  • MIL on after the second faulty trip
  • Probe disagrees with neighbouring temperatures after a cold start
  • Usually no noticeable change in driveability

Repair estimate

DifficultyMediumDIY possible
Parts and labour€0–350
Time0.3–1.5 h

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

Parts involved

egt sensor b1s4

Related codes

P246EP2470P2471P2472P242BP2080

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