This is most likely an issue some of you will be able to identify quickly. My 03 v6 has 91k miles. All the recent cpu upgrades as far as I know. I cranked it last night and the cel comes on. The car idles fine and revs normal. But, when driven it sputters and cuts out as if it has a misfire. I don't have a code reader and don't want to risk driving it to the dealer tomorrow. I checked all fuses. Any ideas on what this could be?