Toyota Repair: 1993 Toyota Corolla Gas Mileage, engine management systems, toyota corolla

Question
 I have an old 1993 Toyota Corolla 1.6 liter engine EFI. My average fuel consumption is almost 19 MPG, can you teach me on how can I increase fuel mileage for my old car? What parts do I need to clean or change? I've bought a new genuine air filter from Toyota, and also changed my spark plugs to Denso's Iridium Tough.

Answer
Hi, this is really hard to tell. Firs you have to know if your engine is mechanically OK, then all engine management systems are working OK. otherwise will will end up spending money and not achieving results. And last but not least is your driving style.