Is there a way to find the code without a scan tool?? Truck is all stock except a afe drop in filter that I put in 10,000 miles ago. Truck has 31,000 miles on it and this is the first issue. It is very cold today (it was below 0 and now is 9) and I put on the grill section of the winter cover for the first time. Any help would be great, I did hit onstar and they showed no problems. Need to head to NC in the AM and hoping its not a big deal.