DEF system questions -2014 duramax
1. How much DEF should I be using. Used about 2.5 gallons in 700 miles. I think this is high based on what I have read but not sure where to look for a problem.
2. I had a P21dd - reductant heater 1 current low code. Cleared it and has not returned but only been 1 day. Not able to find much about what part would be the issue if this code returns. Looked at the gmdirect parts breakdown and it does not list the heater.
Suggestions or ideas?
Cleared code, no return yet
Cleared the code on Thursday evening. Drive all but Saturday and has not returned. I had seen the Cruze info but that is all so far.
Filled the def tank at a Speedway station. Put in 5 gallons and we will see how long it lasts. Kind of a pain since the hose had to be stretched across the engine compartment as I did not go into the station backwards.
Good to know that others have not had this issue.
Will update if the code returns
Code returns after 7 days
Drove the truck 5 of the last 7 days and the code came back in the middle of the day. Temp was 55 at the time so not sure what temperature the heater turns on at but has been cooler than this most days. Was raining at the time but doubt that would have an effect. Cleared the code again.
Unless GM has a really extended warranty, with 152,000 miles, it won't see a dealer for repairs.