I just received notice, dealer says it's in regaurd to the cold start issue a lot of us have had. Requires a ECM flash and software upgrade. Dealer also advises they have not had any feedback from customers after performing this software upgrade. I am concerned, that this will effect milage or proformance. On a previous truck a software upgrade cost me 2-3 mpg, and when I questioned the dealer about reverting to the previous software version they informed me that EPA will not allow this. Once ECM software is upgraded, the dealer must only install the latest version. Has anyone had this software upgrade for the cold start problem, and if so how is it working?

 

What year Truck, what motor?

 

2003 screw w/4.6