2917 Duramax problems, codes and service problems

FreeAmerican · July 22, 2017

Its been a frustrating couple of weeks. Week before last when towing my camper for a short vacation the CEL pops on. So I immediately hop on the My Chevy app and schedule a visit to the dealer the following tuesday.

Tuesday comes and I go to drop off the truck and get my loaner to go to work. So there is some issue where the apt scheduled on the app doesn't show up in my dealer's system and they don't have a slot or loaner for me. But they work me in but by this time the shuttle leaves and by the time I get to work, my boss is mad, I'm mad.

So the code ends up P20EE, NOx sensor bad. They have to order it in. Manager apologizes for the scheduling issues and says he will have me a loaner. I get there and you guessed it, service rep has no idea whats going on, they have to dig up a loaner..... an hour later I go home!

Truck is to be ready at lunch but no go, still working on it. Pick it up on the way home and things seem ok with it.

Two days later, light is back on! UGH! I have a scanner so I check it, now its P204C, Reductant pressure sensor circuit low... So now I am back in on Monday.

I am starting to think I should have bought something else.

newdude · July 22, 2017

Hang in there. We've sold 5 of these new ones, only one truck has come back but he has a communication error somewhere. The other ones no issues. One guy tows boats for his customers (big and small) and put it to work day one and has only done an oil change so far.

There was a couple bulletins for ECM reprogramming for some issues on them, but I don't recall if they pertained to the codes you had.

FreeAmerican · July 22, 2017

For a truck with less than 2000 miles on it and costing 70k. I am a bit more than just frustrated. I love the truck otherwise. And part of my frustration is with my dealer. I've had great service from them in the past, so I am hoping this was just an "off" day.

Colossus · July 22, 2017

I am starting to think I should have bought something else.

You could have.. but what makes you think you wouldn't have problems with something else? Regardless it sucks though!!

FreeAmerican · July 22, 2017

You could have.. but what makes you think you wouldn't have problems with something else? Regardless it sucks though!!

Very true.

FreeAmerican · July 25, 2017

A quick update, I dropped it off at 7:30 this morning, When I did not hear anything by lunch I figured this was not going well. So at 5 they give me a loaner and tell me the technician has been at it all day, running tests, then calling GM, GM telling him to run more tests.

I am due to tow my camper this weekend, the mrs is not going to be happy if we don't have a truck.

Colossus · July 26, 2017

that's ok. They're never completely satisfied anyway.

FreeAmerican · July 26, 2017

So the technician talked to GM, GM thinks a bad DEF wiring harness caused the earlier and the current faults. GM overnighted a new harness.

newdude · July 26, 2017

So the technician talked to GM, GM thinks a bad DEF wiring harness caused the earlier and the current faults. GM overnighted a new harness.

Good to hear. Typically if a tech gets a hold of GM (they call their Technical Assistance group TAC), the folks at TAC get calls throughout the nation. Lots of times, they have an answer right off the bat as they will have had a similar or exact same case at another dealership somewhere else. They have all sorts of info, from other similar problems at other dealers, to engineering issues, production line issues, etc. TAC is full of some smart folk with lots of data.

FreeAmerican · July 26, 2017

More bad news. First the harness did not make it in today but they think it will be here tomorrow in the AM.

But now they are backing off how long it will take to install it. They are now saying it may take 1-2 DAYS to install the harness.... I was told it was a DEF harness. Does this sound reasonable?

Its too late to cancel my camping reservation this weekend. I'm out $120 for that if this all falls through.

Do I have any recourse to ask for a truck capable of towing as a loaner?

FreeAmerican · July 26, 2017

I'll add this is my second trip in, 2 days the first time, now 3+ days this time.

newdude · July 26, 2017

More bad news. First the harness did not make it in today but they think it will be here tomorrow in the AM.

But now they are backing off how long it will take to install it. They are now saying it may take 1-2 DAYS to install the harness.... I was told it was a DEF harness. Does this sound reasonable?

Its too late to cancel my camping reservation this weekend. I'm out $120 for that if this all falls through.

Do I have any recourse to ask for a truck capable of towing as a loaner?

If its one of the two harnesses that are in/on the tank, its not a 1-2 day job. Now, if they were trying to get the engine harness side plug that goes to one of those DEF harnesses, then yes its a day or two. If that's the connector they needed, they have to change the whole engine wiring harness.

Is your trailer conventional hitch or a 5th/goose?

FreeAmerican · July 26, 2017

If its one of the two harnesses that are in/on the tank, its not a 1-2 day job. Now, if they were trying to get the engine harness side plug that goes to one of those DEF harnesses, then yes its a day or two. If that's the connector they needed, they have to change the whole engine wiring harness.

Is your trailer conventional hitch or a 5th/goose?

Bumper pull

8lugCT · July 26, 2017

Bumper pull

if anything have them rent you a uhaul truck

FreeAmerican · July 26, 2017

If its one of the two harnesses that are in/on the tank, its not a 1-2 day job. Now, if they were trying to get the engine harness side plug that goes to one of those DEF harnesses, then yes its a day or two. If that's the connector they needed, they have to change the whole engine wiring harness.

Is your trailer conventional hitch or a 5th/goose?

If it is the main harness, do you know if this means pulling the cab up? I had someone tell me that...