Car ran fine. Now it won''t start. It turns over and will fire if starting fluid is sprayed into the intake. Changed the fuel pump relay because it''s cheep. No change. Also noticed that there is zero movement of the gas guage but other guages work fine. Mechanic says there is no injector pulse but he also insists this model uses a key with a "chip". I never had a key with a chip since I bought the car three months ago. help!