When does an engine need rebuilt?

How do you know when an engine needs to be rebuilt?

My 1991 SL1, 1.9L SOHC, has about 225,000 miles on it. It is not running right now, but I feel that is because of a fuel delivery problem and/or electrical issue, as I have posted elsewhere.

Gas mileage was still good, but it does use some oil. Does the PSI compression test tell us much. All cylinders are around 160 psi. I don't know what it is supposed to be when the engine is like new, does anyone know?

This engine looks simple enough to rebuild, if I need to do it. I would like to do it for minimal parts, and whatever machine work has to be done; basically less than $500.00 if possible.

Has anyone been through this before?

Thanks

T. Smith

i have done the math and i don't think rebuilding on a $500 budget is impossible. the compression test is one of the best test of an engine's internals. the spec is 180PSI@ 10 strokes wet. the sound of a engine and the oil life are some basic factors.