Ok, where to start. P2002. I
My first Cruze Diesel threw that code in the first week... And it was a bad DPF. Ask your serving dealership to do a full thottle test... If you get smoke out the tail pipe, you have a damaged DPF.. and the do NOT want to eat the cost to replace it, they are generally over $1000 sometimes closer to $2000. If you have soot in your tail pipe.. that is another sign. What is your driving profile, if it's considerable city stop and go.. the emmisions systems on these cars just don't do well with with that type of driving..
Now the clunck is a transmission problem. These cars go into free wheel ( Engine disconnected from Transmission via electronic clutch when you come to a stop, this is a fuel saving feature, it avoids waste of churning fluid in the torque converter. In your case it's disengaging harshly.. one thing to consider, are you running original Transmission Fluid? The service interval would have you believe it is a lifetime fill, that is BS. I changed my high mileage car shortly after I got it, about 43k miles and it was some seriously worn out black fluid that looked awful. New fluid GREATLY improved shift behavior. There is an excellent write up in the How to section of the gen 1 Diesel section of this forum. I'd start there and if it still has issues, it's something more serious, and that warranty should cover, in fact I think the standard power train warranty is still active for you. Good luck and post updates as you work to resolve this.
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