How to Replace a Fuel Injector in a Chevy Cobaltby Contributor
The Chevy Cobalt mixes fuel and air under pressure with a fuel injector. This function was previously performed passively by carburetors until the late 1980s. One advantage of fuel injectors is the programmable firmware that allows the fuel injector to handle different fuels. A fuel injector is comprised of only the nozzle and valve; it still requires the pump to pressurize the fuel.
Determine which fuel injector your Chevy Cobalt needs. This depends not only on the make and model, but also the engine size. You will have one of the following engines: 2.0 L S/C LSJI4, 2.0 L Turbo LNFI4, 2.2 L L61I4, 2.2 L LAPI4 or 2.4 L LE5I4.
Disconnect the negative battery cable with a socket wrench and relieve the fuel system pressure. Remove the coolant overflow pipe and disconnect the fuel supply pipe from the fuel rail with a back-up wrench. Unfasten the mounting studs on the fuel rail with a socket wrench.
Pull the fuel rail back and upward to remove the fuel injectors from the cylinder head ports. Rotate the fuel rail so that the injectors are positioned downward and then remove the fuel rail.
Remove the wiring harnesses for the fuel injectors. Release the retainer clip for the fuel injectors and remove the fuel injectors. Remove and discard the fuel injector O-rings.
Install the new fuel injectors by reversing the removal procedure. Lubricate the new injector O-rings with clean engine oil.
Use a torque wrench to tighten the fuel rail studs to 89 in. lbs. and torque the bolts on the fuel supply pipe to 10 ft. lbs. Torque the bolt for the coolant overflow pipe to 71 in. lbs.
Turn the ignition on for 2 seconds, off for 10 seconds and start the engine to check for fuel leaks.