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Diesel Engine Surge at 1100 to 1400 RPM - keywords calibration chuggle ECM idle software speed update

Subject:Diesel Engine Surge At 1100 to 1400 RPM

Models:2004-2005 Chevrolet Silverado
2004-2005 GMC Sierra
Equipped with the 6.6 LLY Duramax Diesel Engine



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

The customer concern may be an engine RPM surge at 1100 to 1400 RPM.

This condition will occur at slow speeds, and may be more noticeable when towing.

Recommendation/Instructions:

  1. Complete the current SI diagnostics for any symptoms or DTCs set.
  2. A new calibration has been released for a 1100 to 1400 RPM low speed surge.
  3. If the 1100 to 1400 RPM surge has been duplicated, install the updated calibration and evaluate repairs.

Note: 2004-2005 6.6L Duramax Diesel equipped vehicles with a manual transmission are not included in the software update. If the 1100-1400 RPM surge is verified in a manual transmission equipped vehicle please submit a Field Product Report. Instructions for completing a Field Product Report can be found in bulletin number 02-00-89-002D.

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.