Possible fuel injection trouble?

I own a 99 Toyota Corolla that I am trying to drive into the ground. It currently has 90,000 miles so for a Toyota I should have several more years left. It recently started puttering when I initially start to take off and the mechanics have been unable to diagnose the problem thus far. They thought it was the motor mount but they replaced it and the problem persists. Then twice today the car would not start when the emergency brake was on but started easily when I released the brake. Can anyone help me determine what may be going on with my car? Are these two issues related?

It seems that the “driving it into the ground” part has already happened. Install fresh spark plugs and check the sparks. If it still “stumbles”, replace the spark plug wires.
Clean the entire intake tract: MAF (Mass Air Flow) sensor with MAF cleaner; Throttle Body cleaner for the throttle body and bore, and the idle air control valve air passages.

PS, Would you let us know if you do any of these things? As fixes, they are about as cheap as you can go.