sorry guys new here!

any one got info on this reflash

04.5 lly

Welcome aboard, just do a search for reflash.. get some coffee and enjoy, you'll find all you ever wanted to know

Document ID# 1625742
2004 Chevrolet Chevy K Silverado - 4WD


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2004-2005 6.6 LLY Diesel Engine Surge At Idle or 1100 to 1400 RPM - keywords balance brake calibration ECM engine fuel injector regulator #PIP3328A - (Mar 14, 2005)
2004-2005 6.6 LLY Diesel Engine Surge At Idle or 1100 to 1400 RPM

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

Condition/Concern:
The customer concern may be an engine RPM surge felt at idle or at 1100 to 1400 RPM. This condition may be more noticeable when towing.

Recommendation/Instructions:
Complete current SI diagnostics for any DTCs set.
Verify the vehicle has the newest ECM calibration. There is a calibration available for an off-idle 800 RPM surge.
There are two distinct engine RPM surges this pi will address.
The first surge is an idle surge that is felt when the driver's foot is on the brake, there is a very low or 0% APP angle, and the vehicle is stopped. This idle surge can be duplicated by coming to a stop, then slightly releasing the brake to let the vehicle roll forward.
The second surge is felt in the 1100 to 1400 RPM range. This surge is felt more when cruising at a steady speed in the 1100 to 1400 RPM range.
Monitor the injector balance rates at idle. Injector balance rates should be between -4.0 to +4.0 in park/neutral and -6.0 to +6.0 in drive. If balance rates are not within these specifications continue injector diagnostics following SI procedures for Fuel Injector Balance Test with a Tech 2.
If the condition of an engine RPM surge can be duplicated and all balance rates are within specifications do not attempt repairs. Engineering is investigating the 6.6 LLY diesel engine surge at idle and at 1100-1400 RPM. This PI will be updated as soon as new information becomes available.
Please follow this diagnosis 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.

Models:
(2004-2005 Chevrolet Silverado) and (2004-2005 GMC Sierra)



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Document ID# 1625742