Hi, Doug --
I'll echo the advice that it might be a good idea to doublepost under the Hot Rods heading, or Performance Paddock.
66K sounds early for there to be significant chain stretch. I had thought the earliest you would see that would be in the 80K range. If it in fact needs to be done, it'll set you back anywhere up to the low $1K+ range with all the trimmings, but that would be a lot cheaper than a failure!
My car had a failed wiring harness (search on my moniker and the term "wiring harness" for my experience). 66K is probably not too early for that to go out.
Check my notes on how to self-diagnose that. Again, it's costly to leave unfixed. A shorting harness can take out certain underhood components (throttle actuator, if I recall correctly).