Changing Fuel Injectors
Scott Simpson
Procedure
Changing the fuel injectors on the '84-'87 turbo regals is actually simpler than it looks. When I first looked under the hood of mine, I thought I'd never be able to figure out all this wiring and injector stuff when I was so used to a carburator. Never fear, here are some step by step instructions to help guide you through the injector replacement process.

1. Clean the engine off to get all the dirt/dust/grime away from the general area of the fuel rail and injectors.
2. Depressurize fuel system to avoid any fuel spray when disconnecting components. Disconnect the electrical connection just inside the back bumper in the center of the car. This will stop power to the fuel pump. Start the car and let it die. Take out the shrader valve in the fuel rail (be sure to cover it since it might still spray a little fuel) and let the rest of the pressure out.
3. Disconnect the battery.
(You're going to remove the fuel rail so remove everything from it.)
4. Remove coil pack - an explanation supplied by Ken: You undo the 10mm bolt in the back/center of the pack that holds it to the support. Then you undo the two 15mm nuts that bolt it to the studs holding the fuel rail. You can just lift it up out of the way at this point (with harness and plug wires still attached). If this is your first time doing this, I'd recommend you just unplug all the plug wires, undo the big connector and take the coil pack all the way out. It gives you more room.
5. Remove fuel pressure regulator.
6. Remove fuel inlet line.
7. Remove PCV valve and hose.
8. Remove vacuum hoses from top of plenum and the two hoses that are attached to the fuel rail.
9. Disconnect fuel injector connector on driver side behind engine just below where coil pack was.
10. Unbolt four (4) bolts that hold the fuel rail down and remove the throttle body linkages for the throttle and the transmission (TV).

Try to remove the injectors with the fuel rail. This can be accomplished by gently but firmly (may not feel like they're going to come out but they will) prying with a flat head screwdriver under each fuel injector. If you pull up on the injector, you probably can get the tip of the screwdriver under a lip on the injector.

11. Once each injector is loose from its hole in the intake, lift the entire fuel rail including the injectors off.
12. Place the fuel rail and injectors on a towel upside down.(now for each injector)
13. Pull black holding clip off injector.
14. Pull electrical connector off injector.
15. Pull injector out.
16. Put small amount of grease/petroleum jelly on O-ring of new injector.(Use new o-rings, but I'm not sure where to get them. They should come with new injectors)
17. Push the new injector onto the fuel rail.
18. Reconnect electrical connector and holding clip.
19. Keep the cap on bottom of injectors until ready to install.
20. Now that all injectors are mounted on fuel rail, remove caps from injectors.
21. Apply small amount of grease/petroleum jelly to O-rings.
22. Place fuel rail down on intake and align fuel injectors (its easier with two people one on each side but can be done with one).
23. When all injectors are lined up, push down on the fuel rail to seat the injectors.
24. Reattach all hoses.
25. Connect fuel injection wiring harness connector.
26. Mount coil pack, fuel pressure regulator,fuel line,... Be careful not to cross-thread or strip the fuel line connections.
27. Connect battery.
28. Apply 12 volts to the fuel pump test lead (grey wire behind alternator with the black connector). (The connector going to the hood light makes a perfect connection or you can also use a wire to the V+ on the back of the alternator for a feed.) This will supply power to the fuel pump and fuel to the injectors.
29. Check for leaks.
30. When done, Crank her up and take it for a spin.

It really doesn't take all that long to do all this. I've done it twice now and both times were about 1-2 hours.


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