I have a 2001 Grand Prix that I absolutely adore. I've driven it across the country - literally LA to JAX twice and it has been the most reliable and awesome car I have ever owned and I've had quite a few over the years. Now, the problem. It has suddenly started "shivering" when running and the Check Engine Soon light has come on. It's been hard shifting for a little while and the speedometer sometimes goes haywire (doing 80 at a full stop). I know I've been neglectful in not getting this checked out but this latest rough running and the flashing light has me alarmed. Any ideas out there on what the problem might be? Don't want to pay hundreds of dollars to find out it's a quick and simple fix.
