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Roughness Or Vibration At Idle - keywords 07 6.0L engine fuel injector LY6 misfire miss plug rough spark sparkplug vibe

Subject: Roughness or Vibration At Idle

Models:2007 Chevrolet Silverado, Suburban, Tahoe
2007 GMC Sierra, Yukon
Equipped with the 6.0L engine RPO code LY6



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

Condition/Concern:

The customer concern may be a roughness or vibration that is felt at idle.

Recommendation/Instructions:

Complete the current SI diagnostic for any trouble code or symptom found. If the diagnostics for Rough, Unstable, or Incorrect Idle have been completed and are inconclusive, compare the concern to a like vehicle.

GM is aware of the customer comments regarding roughness or vibration at idle. If normal diagnostics determine that the vehicle is operating within design parameters, no repairs should be attempted. The idle roughness should be considered a characteristic of the vehicle. The roughness is due to a stiffer engine mount, and the heavy duty frame used on these applications.

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.