1991 Infinit G20

we have a 91 G20 which has been a great car but it now needs about $1000 to get it running again. It needs a new muffler, new tires and a tune-up. Is it worth putting that much into such an old car or should we put that towards a newer used car? Opinions?

The things you mention are basically normal maintenance and wear items. If you bought a NEW car you would be replacing tires in 5 years, tuneup in 6, and new muffler in 7 maximum!

If the engine is sound, the transmission working well, the air conditiong functioning OK, and the body has little or no rust, You will save money by repairing this basically excellent car. If this was a Plymouth Breeze or similar short life vehicle, I would dispose of it.

I agree with Doc 100% on this one. Even about the Breeze.