Powertrain, generic (extended)

P2428 Exhaust Gas Temperature Too High (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2428 is a protection code: the exhaust on bank 1 has become hot enough to endanger the aftertreatment, above all the diesel particulate filter. GM's 2014 diesel tables (14OBDG04) list five triggers, any of which fails the test after 6 seconds: about 800 °C ahead of the oxidation catalyst, 900 °C behind it, 800 °C behind the filter, or rises of more than 600 °C across the catalyst and 400 °C across the filter. The fault is Type A, so the lamp comes on at once. The usual origin is an uncontrolled soot burn in the filter, late fuel injected during regeneration or a leaking injector. CARB requires plausible EGT sensors, so a faulty sensor must be ruled out first. Engine power is usually limited.

Likely causes

Uncontrolled soot burn in an overloaded particulate filter
Leaking injector or excessive post-injection reaching the catalyst
Exhaust temperature sensor reading too high

Symptoms

  • Warning lamp on immediately, often with reduced power
  • Strong heat or burning smell from the exhaust
  • Particulate filter or catalyst damage in severe cases

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–3,000
Time1–6 h

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

Parts involved

exhaust gas temperature sensor b1dpf b1diesel oxidation catalyst

Related codes

P2429P2463P242FP0544P2080

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