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P1621 Diagnostic Trouble Code Discussion for July 2013

Control Module Long Term Memory Performance


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Trouble Ticket Help Requests for DTC P1621
Help Request Posted
2005 GMC Sierra 3500 SLT 6.6L Excessive Emissions VIN: 1GTJK33265
P1621: Control Module Long Term Memory Performance. ... injecters trucks run great it just smoke under load or when pulling it leave a big clould on take off and leaves a light stream untill you let out of the gas or back off to 1/4 throttle i flow tested all my injecter and did a return test again whice is all...
July 18, 2013
2005 GMC Sierra 3500 SLT 6.6L Excessive Emissions VIN: 1GTJK33265
P1621: Control Module Long Term Memory Performance. ... injecters trucks run great it just smoke under load or when pulling it leave a big clould on take off and leaves a light stream untill you let out of the gas or back off to 1/4 throttle i flow tested all my injecter and did a return test again whice is all...
July 19, 2013
2005 GMC Sierra 3500 SLT 6.6L Excessive Emissions VIN: 1GTJK33265
P1621: Control Module Long Term Memory Performance. ... injecters trucks run great it just smoke under load or when pulling it leave a big clould on take off and leaves a light stream untill you let out of the gas or back off to 1/4 throttle i flow tested all my injecter and did a return test again whice is all...
July 18, 2013
2005 GMC Sierra 3500 SLT 6.6L Excessive Emissions VIN: 1GTJK33265
P1621: Control Module Long Term Memory Performance. ... injecters trucks run great it just smoke under load or when pulling it leave a big clould on take off and leaves a light stream untill you let out of the gas or back off to 1/4 throttle i flow tested all my injecter and did a return test again whice is all...
July 19, 2013