Here is a little write up of some emissions issues I had recently, had trouble researching these codes and a fix so hopefully this helps someone out there.
2017 Chevrolet Colorado Duramax w/ ~55k miles, everything OEM.
Check Engine light illuminates, scan shows P20EE "SCR NOx Catalyst Efficiency Below Threshold Bank 1". ~50 miles later another code is present, P11D5 "NOx Sensor 2 Exceeded Minimum Learning Limit". Only other strange symptoms are fuel economy has gone down, and latest regen dropped ~100 miles between regens, down to 330 miles between regens.
Original purchasing dealership informally advises to remove MAP sensor & clean. FB group advises to replace NOx sensors. Didn't do either but I will clean MAP sensor when I am able to, and I now have a spare #2 NOx sensor.
Brought truck to local dealer and advised them of the P20EE & P11D5 code. They called me and advised that the DEF pump was receiving electricity, but not working properly and failed the DEF quantity test. They said the DEF pump and DEF module would need to be replaced.
1. DEF Pump (84526247) Rock Auto Price $443.79, Chevrolet List Price $1,077.99
2. DEF Module (39153712) Rock Auto Price $131.79, Chevrolet List Price $348.99
The dealer replaced these two parts and advised that they confirmed the two codes (P11D5/P20EE), that they tested the reductant pump not building enough pressure for the system to actuate the reductant injector and make the converter hot, causing code P20EE, and that they replaced the reductant pump and controller. They also advised that they added 2 Gallons of DEF. Chevrolet's list price for DEF is $12.95 a gallon, a lot more than what I usually pay.
I am away for work and unfortunately could not perform the repair myself. The Chevrolet parts listing price is excessive and I was able to negotiate with the dealer a somewhat more reasonable price, which was appreciated. I wish that they didn't add any more DEF. I had my tank only 1/2 full on purpose. It's the winter where I live currently and it will be getting below 12F at night, I didn't want my DEF to freeze and then expand with a full tank.
Emissions warranty didn't cover any of the repairs. From my research my State tags along with the California emissions warranty and the products that broke on my truck are only warrantied for 5 years or 50k miles, so I had to pay the $1,700+ repair bill on my own.
Emissions is the worst part about this truck. GM's parts listing price was so excessive on these emissions components that it has really turned me off as a Chevrolet customer.
2017 Chevrolet Colorado Duramax w/ ~55k miles, everything OEM.
Check Engine light illuminates, scan shows P20EE "SCR NOx Catalyst Efficiency Below Threshold Bank 1". ~50 miles later another code is present, P11D5 "NOx Sensor 2 Exceeded Minimum Learning Limit". Only other strange symptoms are fuel economy has gone down, and latest regen dropped ~100 miles between regens, down to 330 miles between regens.
Original purchasing dealership informally advises to remove MAP sensor & clean. FB group advises to replace NOx sensors. Didn't do either but I will clean MAP sensor when I am able to, and I now have a spare #2 NOx sensor.
Brought truck to local dealer and advised them of the P20EE & P11D5 code. They called me and advised that the DEF pump was receiving electricity, but not working properly and failed the DEF quantity test. They said the DEF pump and DEF module would need to be replaced.
1. DEF Pump (84526247) Rock Auto Price $443.79, Chevrolet List Price $1,077.99
2. DEF Module (39153712) Rock Auto Price $131.79, Chevrolet List Price $348.99
The dealer replaced these two parts and advised that they confirmed the two codes (P11D5/P20EE), that they tested the reductant pump not building enough pressure for the system to actuate the reductant injector and make the converter hot, causing code P20EE, and that they replaced the reductant pump and controller. They also advised that they added 2 Gallons of DEF. Chevrolet's list price for DEF is $12.95 a gallon, a lot more than what I usually pay.
I am away for work and unfortunately could not perform the repair myself. The Chevrolet parts listing price is excessive and I was able to negotiate with the dealer a somewhat more reasonable price, which was appreciated. I wish that they didn't add any more DEF. I had my tank only 1/2 full on purpose. It's the winter where I live currently and it will be getting below 12F at night, I didn't want my DEF to freeze and then expand with a full tank.
Emissions warranty didn't cover any of the repairs. From my research my State tags along with the California emissions warranty and the products that broke on my truck are only warrantied for 5 years or 50k miles, so I had to pay the $1,700+ repair bill on my own.
Emissions is the worst part about this truck. GM's parts listing price was so excessive on these emissions components that it has really turned me off as a Chevrolet customer.
