Hello again.... I found a post on this site from Feb 2002 of someone looking for what sounds like the same book I am. Unfortunately no replies though and the email provided is no longer active. I thought of a couple more details that may spark someone's memory... the car was red, it goes around helping people all day, saying something like "it's all in a day's work", and toward the end of the book the car gets stuck and has be accept help from others, maybe a tow truck...

Any help would be appreciated, thank you!