P050D Cold Start/rough idle

Tgarner15 · September 29, 2019

Bought a 2016 GMC Yukon XL with 52k on it last November, this spring it started throwing this code, we would put in Lucas and it would go away after a day and stay off for weeks to a month. In August it became an every other week deal, 3 weeks ago it also had a Cylinder 6 misfire where we changed all the spark plugs, it does run better overall since changing but has since came up with the same code once again and isn’t going away this time...husband and his uncle who is a mechanic are stumped, we are supposed to drive to Florida in 3 weeks for a family wedding so we’d really like to get this figured out, it’s not in warranty anymore with 75K on it now...anyone have any similar issues and resolutions!! So frustrating to have such a new vehicle with these big problems as we had to replace the condenser in it also this summer!

The Zip · September 29, 2019

48 minutes ago, Tgarner15 said:

...husband and his uncle who is a mechanic...

Had something similar but on a Chevy. Pull the number 6 fuel injection wire and check the condition. If good, pull the injector and clean or replace and see if the idle levels and code disappears. If you replace, you could probably do it for about 60 bucks, cheaper than renting a vehicle to catch the wedding. If this works, drop some STP concentrated fuel injection cleaner in the tank for a little insurance.

tbarn · September 29, 2019

Special policy for injectors depending what state you are in. Most likely injector failure.

Some 2016 and 2017 model year Cadillac Escalade, Cadillac Escalade ESV, Chevrolet Silverado, Chevrolet Suburban, Chevrolet Tahoe, GMC Sierra, GMC Yukon, and GMC Yukon XL vehicles, equipped with a 5.3L or 6.2L engine, may have a condition which affects fuel injector function. Under certain circumstances one or more of the vehicle’s fuel injectors may deliver an improper amount of fuel to the engine. If this occurs, the Malfunction Indicator Lamp (Check Engine Light) will illuminate, the engine may idle or run rough, and the vehicle may stall. A diagnostic trouble code related to the fuel injector may be set. This special coverage only applies to vehicles in these states: California, Connecticut, Delaware, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, and Washington.

Prospect62 · February 9, 2020

Just in case anyone starts having this issue...

https://static.nhtsa.gov/odi/tsbs/2019/MC-10163854-9999.pdf

There's your golden ticket. Just had mine done last week. I was sure it was an AFM lifter failure, turns out it was #3 and #5 injectors gone bad. Keeping the notice for when the others go out...

King Matt · June 8, 2022

Does anyone know why Texas is not a state listed? I have this problem but they are telling me that the notice doesn’t apply to my vehicle because I live in Texas.

newdude · June 8, 2022

10 hours ago, King Matt said:

Does anyone know why Texas is not a state listed? I have this problem but they are telling me that the notice doesn’t apply to my vehicle because I live in Texas.

Because those states have adopted California or CARB emissions. Only 13 of the 50 states.

Edited June 8, 2022 by newdude