He said that there's another part that needs replacing if I'm going to pass my next smog check, but he had to order it from the GM dealership and it won't be here until Friday. I explained that I do need need a smog check -- it's due before the end of November -- and he said that if I brought the van back on Tuesday morning, he can replace the part and have one of his neighbors, whose shop is a smog-test-only station, do the smog as well. That sounds good to me.
I offered to pay for the work that has been done so far, and he told me to not worry about it until after we get the rest of the work done on Tuesday, so we can settle it as one bill. The total damage is going to be more than $1000, but less than $1500, it appears. But as I've said before, it's a pleasure to work with an ethical, talented mechanic like this. Looking at how busy his calendar is, he probably doesn't need me talking him up, but I will anyway.
As I drove away, I could definitely feel a significant improvement in acceleration and engine feel, so he's not kidding about having fixed things.