Save your prayers for something more important.
I own a 1987 Toyota Camry, automatic transmission, that has a "chipped flywheel." My mechanic said it develops when the starter key is turned on while the engine is already running. I can remember two times when I did this. Once it was noisy, and I couldn't hear the engine, and the second time I was distracted and forgot that the engine was running. What happens now is that once or twice a week, approximately two out of 28 engine starts, there is a gut wrenching grinding noise. When it happens, I quickly turn off the key, say a prayer, and try again. It always starts. My mechanic says replacing the flywheel will cost $500. Please give your opinion about replacing it.
TOM: You should replace it, Sylvia. The praying may be having some effect now, but our mechanical experience strongly suggests that at some point, you'll be praying for a tow truck or a ride to work.
RAY: The flywheel has a gear on it called the ring gear. And when you turn your key to start the car, a little gear on the starter pops out and meshes with this ring gear. If the starter gear pops out while the ring gear is already turning (i.e. while the engine is running), you can break teeth on the ring gear. And that's what happened.
TOM: Then, when you turn the engine off, the ring gear stops spinning. And if it happens to stop so that the broken teeth are right opposite the starter, then the next time you start the car, you'll get that ferocious grinding.
RAY: And each time you grind the flywheel, a little more of it gets chewed up. So that eventually, if you don't fix it, you're going to get stranded somewhere.
TOM: So get it fixed, and save your prayers for something more important--like a winning lottery ticket or a lifetime supply of Bronko Nagurski long underwear.