DIY E36 Injector for a BMW

Removing Old Injectors
1. Open the hood and locate the fuse box, a black box on the driver's side. Open the fuse box and remove the fuel pump fuse.
2. Attempt to start your car several times after pulling the fuse, which will cause the car to turn over and die. Repeat this about 10 times to drain any excess fuel from the injectors.
3. Remove the two plastic covers at the top of the engine by prying off the circular caps with the flathead screwdriver and unscrewing the securing bolts using the 10 mm socket.
4. Using your hands, pop off the thin plastic cover that sits at the center of the engine bay and covers the wiring harness for the E36's spark plugs and injectors.
5. Remove the two 10 mm bolts that secure the wiring harness to the top of the engine's intake manifold.
6. Remove the connectors from each fuel injector using the needle-nose pliers. Disconnect the wires that secure the connectors to the fuel injectors.
7. Lift the wiring harness up and set it aside to reveal the fuel rail where the injectors sit.
8. Remove the six black plastic square clips that secure each injector to the fuel rail by using the needle-nose pliers.
9. Lift the fuel rail up from the top of the fuel injectors by starting from the back and moving forward, applying light force as necessary. The fuel rail is metal and can easily bend, so be careful.
10. Position the fuel rail aside and pull each injector out of the intake manifold by lifting straight up.
Installing New Injectors
11. Insert the six new injectors into the intake manifold.
12. Re-attach the fuel rail by positioning it above the fuel injectors and pushing straight down working from the front to the back of the engine.
13. Position the wiring harness above the fuel rail and slide on each of the six clips to secure it back into place.
14. Re-connect the fuel injectors to the wiring harness by using the needle-nose pliers.
15. Position the large plastic engine covers over the engine and secure them into place using the 10 mm socket wrench. Snap on the circular bolt covers to complete the fuel injector replacement.