P2428: Exhaust Gas Temperature Too High Bank 1

What it means

The control module detects exhaust gas temperature above its calibrated limit on Bank 1. The cause and consequences depend on the vehicle and operating conditions.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test

How it works

Bank 1 is the engine bank that contains cylinder 1, and its exhaust temperature may be measured by one or more sensors along the exhaust. The control module sets P2428 when it detects Bank 1 exhaust gas temperature above its calibrated limit, which can happen during regeneration or when exhaust flow, temperature sensing, or combustion is abnormal.

Common causes

Most likely first.

1. Restricted exhaust or particulate filter
2. Active or prolonged DPF regeneration
3. Faulty exhaust temperature sensor or wiring
4. Excessive fueling or combustion heat

Symptoms

• Check-engine light or exhaust-system warning on
• Reduced engine power
• Cooling fan running after shutdown

How to diagnose it

1. Record freeze-frame data and check live exhaust-temperature readings, regeneration status, and related fault codes to identify when Bank 1 became too hot.
2. Inspect the Bank 1 exhaust-temperature sensor wiring and connectors for heat damage, loose pins, or corrosion.
3. Compare the Bank 1 temperature reading with other available exhaust-temperature readings when the engine is cold and during warm-up for an implausible sensor signal.
4. Check for restricted exhaust flow or a loaded particulate filter using the vehicle’s scan data and service procedure.
5. If the sensor and exhaust path appear sound, investigate prolonged regeneration or excessive fueling and combustion heat.

Common fixes

• Repair heat-damaged or loose Bank 1 temperature-sensor wiring or connections.
• Replace a confirmed faulty Bank 1 exhaust-temperature sensor.
• Address a restricted exhaust or particulate filter according to the vehicle’s service procedure.
• Correct a fueling or combustion problem causing excessive exhaust heat.

Can I keep driving?

Avoid towing, steep climbs, and hard acceleration while the exhaust-temperature warning or reduced power is present. Excess heat can damage exhaust after-treatment components; stop safely if a temperature warning escalates.