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Hello everyone!! I'm somewhat new to this site and it looks like I need some help. Here's what I have: 2002 Tahoe 4.8L with 170,000 miles. Over the past few weeks I've noticed when it gets really cold at night (teens or 20's), and I go to start in the A.M., it cranks a while before starting...

Hi and Thanks in Advance for any help or advice. I have a 2002 Tahoe LT (5.3Z-Flex Fuel) with 95,000 miles which has been having a few issues lately. 1) Cold Start (<45 degrees) Rough Idle and Code P0300. When starting the car in cold weather it first revs up to 2000-2500 rpms for a few...