Check engine

I would also get an second opinion, being that the vehicle still functions it's worth the effort. I have had the computer go out on an older car before, it just died and would not restart. Now cars/trucks have several computers running the vehicle, it's almost to much. I really like my 69 truck, no computer, everything mechanical and it always runs.... Good luck, keep us in the loop, interested on how this goes. Btw I had an problem with my 02 truck a few years back when we were camping. Truck ran but was dropping cylinders. Took it to Chevy and they wanted me to buy a new fuse box and computer..... Ouch....... I said no, got it home and diagnosed myself and found it was just a crank position sensor that was going out..........so I never trust what one stealer ship or mechanic will tell u.