with proper mantaince. how long will my engine last
There is no possible way to answer that question .
It’s almost 24 years old. There is no way to know how it was maintained in the past. Pay for a prepurchase inspection and see if it is basically sound. If it is, the engine should last a few years.
how many miles?
automatic or manual?
is it in good mechanical shape . . . or does it have the consistency of swiss cheese?
maintained well, by the book, or not so much?
Those are rugged and simple engines. Over 200,000 miles is well within reason with proper maintenance and operation. Other things (body rust, transmission, a crash) are more likely than the engine to bring on the demise of the car, or the point at which it doesn’t make sense to keep spending on it.
Does your 95 Prizm have the 1.6L 4AFE or the 1.8L 7AFE engine? My 92 Corolla has the 4AFE, and it is still going strong w/over 200K miles. As long as it is properly maintained and the car isn’t abused, unlikely the engine life will determine the life of the car. Rust or transmission failure will be the deciding factor I’d guess. Especially if you have the 5 speed manual, this car is a keeper, and has classic possibilities at some point.
I would be surprised if the Geo Prizm ever has classic status . It was just a throw away 4 door sedan . Now the Geo Metro does have a following but not enough to justify a pricey restoration .
It will come down to is this expense worth it or not, It could last forever given enough money.
Rugged little engine or not, I would count every month as a gift from the great mystery. Maybe the engine will make it but that’s only one part of a 24 year old economy car.