So going to work today around 3 am, temp was around -5 to -10° F, truck was plugged in for about 8 hrs prior to me going to work. Truck started fine, although the coolant temp was only 77° , which kinda sucks compared to my last truck (2nd gen). Now about a mile from the plant, engine light comes on and truck kinda noses over and then runs normal again. Code on my CTS says it was a PO215, injection pump return feed (?). Can't remember it verbatim, but is this something to REALLY worry about? Could it be cold related? Truck was filled yesterday with *********** Service and some OptiLube mixed in. Can I keep driving it til the weekend without doing some type of damage? Or is this something to take care of NOW? Any help here would be greatly appreciated!