The Geo/Chevrolet Prizm was the product of a joint venture between Toyota Motor Corp. and General Motors. It shares the same body style as the Toyota Corolla, employing a 1.6-liter engine on the earlier models. Later, both 1.8-liter and 2.0-liter engines were available. The earlier model Prizms featured an inline fuel filter that required maintenance interval changes of 15,000 miles for carbureted engines and 30,000 miles for fuel-injected engines. However, when GM dropped the Geo name, continuing to build the Prizm under the Chevrolet title, the fuel filter was integrated inside the fuel pump and required no interval maintenance replacement.
Most often, on the 1.6-liter engine, the fuel filter is located on the driver's side firewall in the engine compartment, just below the master cylinder. The carbureted engine sits vertically in a bracket with rubber fuel lines running to it. The fuel-injected filter is held to the firewall with a metal bracket and employs metal fuel lines attached to the top and bottom of it. Later models featuring the 1.8-liter engine placed the fuel filter near the gas tank, under the driver's side rear wheel well.
A simple replacement repair, the carbureted engine needs simply a catch pan below for spilled fuel and a pair of pliers to replace it. Expansion clamps must be relocated further down the rubber line, and then twist the rubber fuel lines and gently pry them off the fuel filter. The fuel filter can then be lifted straight up from the bracket it sits in, being careful not to tip it since it is still filled with fuel. Reinstall the new filter by reversing the procedure.
The fuel-injected engine fuel filter replacement is a bit more challenging. It requires the separation of metal fuel lines from the metal canister fuel filter. Since the fuel system is under pressure, the unions must be unscrewed from one another slowly to relieve the pressure. Obviously, a catch pan strategically located under the vehicle is also required.
Although the separation of the fuel filter and fuel lines sounds like a rather benign task, the connections are tight (because of the fuel pressure) and require two different-sized flare wrenches to gently break the connected line and filter free from one another--without twisting and damaging the fuel line--and then unscrewed altogether. This is the same for both the top and bottom fuel filter to line connections. Remove the fuel filter bracket retaining bolt in order to remove the bracket and then the fuel filter. Note the flow direction arrow indicator stamped on the external canister of the replacement filter since they employ a directional fuel flow. The arrow should point to the upper fuel line running to the engine. Replace the bracket, and the task is complete. Always start the Prizm to check for leaks and tighten the connections if necessary. It will also start harder than normal at first until fuel is restored to the fuel injectors.
