SES Light

[Shire Ben]

Good morning,

I have a 2004.5 LLY with 103,000 miles, completely stock except for Bilstein shocks. No major issues except for Glow plug controller and oil level sensor repaired under warranty. SES light came on the other morning during normal driving conditions to work. Drive approximately 500 miles a week.

Took to local Chevrolet dealer and codes were P0401, P0404 and P1404 which are all related to EGR valve 01 being Flow insufficient, 04 being valve stuck open and 1404 being valve stuck closed. They cleared codes, reprogrammed ECM and truck runs much quieter, but check engine light came on again after trip home. Truck runs fine...ocaasional blue colored smoke on takeoff from stop. Fuel filter coming due so I am going to have them replace that during visit tomorrow, but are there any recommendations for cleaning or replacing EGR to prevent this occurence?

Dealer has always been very good for general maintenance, but not sure how diesel savvy they are...I always feel that it is good to bring information to them as they troubleshoot truck. Any thoughts would be appreciated. Thank you.

[More Power]

Is the air filter clean? I'd change the fuel filter if it needs it anyway. Since you didn't mention an oiled gauze or oiled foam air filter, I'd not assume the MAF sensor needs to be cleaned.

Otherwise, your engine may need some EGR parts.

Jim

[Shire Ben]

Thanks More Power,

Air Filter clean, second DTC was P0101 which was reflashed and no SES. Fuel filter changed, but I believe was unrelated. Still have some occasional blue smoke in AM when truck is cold or starting from stopped position, other than that runs fine. Run fuel supplement every tank. My question is: are they any required cleaning/maintenance for EGR or MAF sensor. Truck has 103,000 miles. Thank you.