Exhaust Gas Temperature Sensor Diagnosis And Repair - keywords 6.6 ash catalyst diesel differential DOC engine filter LMM oxidation particulate pressure regen regeneration sensor temp temperature
| Subject: | Exhaust Gas Temperature Sensor Diagnosis and Repair |
| Models: | 2007 Chevrolet Express, Kodiak, Silverado |
| 2007 GMC Savana, Sierra, Topkick |
| Vehicles equipped with the 6.6 Duramax Diesel Engine RPO code LMM |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
A dealer may encounter a 2007 6.6 Duramax Diesel with Exhaust Gas Temperature (EGT) Sensor diagnostic trouble codes. If EGT trouble codes have been found, and the customer continues to drive the vehicle, the Exhaust Particulate Filter (EPF) may get saturated with particulates. Due to the EGT trouble code being set, the ECM will inhibit the regeneration process.
If the regeneration process is inhibited by any Diagnostic Trouble Code, and the customer has continued to drive the vehicle, the Exhaust Particulate filter may become overloaded with soot.
Recommendation/Instructions:
Complete the current SI diagnostic for any trouble code or symptom found. If a dealer has found an EGT sensor trouble code, and an EGT sensor needs to be replaced, do not continue to drive (or run) the vehicle for extended periods. Driving the vehicle may induce excessive soot loading, and a trouble code P244B may set. If trouble code P244B has set, the ECM has noticed the EPF differential pressure is too high, and EPF replacement may become necessary.
All exhaust system components are on restriction through the Powertrain Quality Center (PQC). Please contact the PQC at 1-866-654-7654 to discuss diagnostics, and order an EGT sensor.
Please do not use the vehicle while waiting on the new EGT sensor to arrive. Replace the EGT sensor and evaluate the repairs. Complete a service regeneration as per SI document ID number 1871446.
Note: All components are vital to the longevity of the Exhaust Particulate Filter system, running the vehicle with any of the Exhaust Particulate Filter Components disconnected may induce excessive soot loading, and a P244B to set.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
