Here is an install thread for injectors. This is mostly based on installing gen 3 bosch into a late model e30 although the steps are similar in the other models and with other injectors.
Tools:
10mm socket. I prefer a shallow as well as quarter inch joint and 6 inch extension.
Flathead
Vaseline/oil/silicone
Needle nose pliers
Other Stuff:
Fresh o-rings
Vaseline (i know twice listed, never can have enough lube)
Optional - Fresh Breather hose
Optional - Fresh valve cover gasket
Optional - Fresh fuel lines if your feeling froggy
Optional - Fresh vacuum line for FPR
Optional - New Coolant temp sender (blue top for ecu)
Optional - contact cleaner
1. Disconnect the battery. I actually dont ever do this but if its good insurance and now you cant say I didnt tell you.
2. It is not necessary to take the intake manifold off at all. I do this process by first removing the valve cover as noted in the picture with the circled nuts. Their is a bracket to the intake that must be removed as well which will be obvious.
3. Also remove the valve cover breather hose from the valve cover and the vacuum line from the intake manifold to the FPR. (I do that just to get it out of the way.)
Note: This is one of those good oppurtunities to replace some other shit. The valve cover breather line and the vacuum line to the FPR are both prone to get old and brittle and break causing vacuum leaks.
4. Unplug the coolant temp sender for the cluster (brown connector) and the coolant temp sensor for the ecu (blue connector). A nice long flatblade can make it easier to push the clips.
Note: This is a good chance to replace your ecu coolant temp sensor. Numerous times this single piece throws people into a furious parts replacing bender. They are cheap and easy to replace. If it is bad your ecu will not meter fuel correctly. Usually itll tell the ecu to run very very rich all the time. If you are installing bigger injectors you want this thing to work right.
5. Unplug the fuel injector harness where it mates to the engine harness. I forget the connector number and I couldnt find a good pic of how to find it so I will describe it as best I can. If you look underneath the intake manifold on the drivers side closer to the firewall side (front to back) down near the middle of the block you will see a bracket with the round connector. The top half is the fuel injector harness and sneaks up under the intake manifold to the fuel injector clips. You need to unlock this harness. It is a round lock. I find it easiest to hold the bottom and twist the lock on the top. One side of this connector also has a plastic retainer nut that holds it into the bracket. You may or may not have to mess with taking the wiring out of the bracket for the note im about to make.
Note: This is a damn good time to check both sides of this connector. This is another one of those things that can cause people major headaches. Often time these connections to the injectors get corroded and can cause some assanine behavior in your car. Now is a good time to thoroughly clean it. I prefer some wurth contact cleaner here.
6. Next you want to remove the injector harness off of the injectors themselves. Now this rail is clipped onto each individual injector. As Ive noted with circles the clips are around each one and you can go to the trouble of trying to get each clip off or cocked 90 degrees. Thats the hard way though. I prefer to grab the harness plastic at the front end and pull up firmly. This should unclip the front half. The grab the rear and do the same. Once the harness is completely free from the injectors just sneak it out being careful to sneak the tail with the round plug up under the intake manifold. Remember how everything went.
7. Now that the harness is out of the way you can remove the fuel lines from the fuel pressure regulator. REMEMBER WHICH WAY THESE LINES ARE CONNECTED FROM TOP TO BOTTOM. LABEL THEM IF YOU NEED TO. One is the feed and the return. Another major headache causer is to hook these up backwards. I did not have a good pic of the far side of the fpr with the lines but i circled it three times so you know to look here for fuel lines.
Once those are disconnected simply remove the four bolts holding the fuel rail to the intake manifold.
Note: If your feeling up to a more involved task you can now take this as a good time to replace those rubber fuel lines in the engine bay. Its a little more involved but those lines will often get old/brittle/fall aparty.
8. Now you can remove the fuel rail with the injectors. I do the same thing I did with the fuel injector harness. Put your hands under it and firmly lift straight up. If you have OEM injectors they are clipped in and will stay with the rail. If not you may have some injectors stay in the intake. Doesnt matter so long as you grab em out.
9. Here is a fuel rail with Gen 3 bosch injectors installed in it. Note on OEM injectors there are clips that hold the injectors into the rail. These clips are not even necessary as the rail is bolted to the intake manifold. On the bosch gen 3 you wont need the clips at all. Just make sure to bolt the rail back into the car when reinstalling. The Gen 3 are the same length as OEM Gen 1 injectors. Make sure to install new o-rings (or buy injectors from me freshly rebuilt with new o-rings.)
I like to use a little bit of vasoline on the o-rings then pop them into the fuel rail. They should go in fairly easy. Make sure they arent pinched. Some people use motor oil or silicone for this as well. Either will work just try to keep it out of the injector filter basket.
Orient the injectors so that they are facing toward the passenger side of the car to make it easier to get the clips lined up.
Reinstall is simply reverse of this whole procedure with a couple of small notes. First when installing the fuel rail before getting carried away pushing the injectors down into the intake holes make sure they are all started and lined up. Once they are all started into the holes a little firm push on the top of the rail should seat them then your rail bolt holes should line right up.
Also dont forget to replace your valve cover gasket if its been a while and those little half donut seals for the head/vc.
Tools:
10mm socket. I prefer a shallow as well as quarter inch joint and 6 inch extension.
Flathead
Vaseline/oil/silicone
Needle nose pliers
Other Stuff:
Fresh o-rings
Vaseline (i know twice listed, never can have enough lube)
Optional - Fresh Breather hose
Optional - Fresh valve cover gasket
Optional - Fresh fuel lines if your feeling froggy
Optional - Fresh vacuum line for FPR
Optional - New Coolant temp sender (blue top for ecu)
Optional - contact cleaner
1. Disconnect the battery. I actually dont ever do this but if its good insurance and now you cant say I didnt tell you.
2. It is not necessary to take the intake manifold off at all. I do this process by first removing the valve cover as noted in the picture with the circled nuts. Their is a bracket to the intake that must be removed as well which will be obvious.
3. Also remove the valve cover breather hose from the valve cover and the vacuum line from the intake manifold to the FPR. (I do that just to get it out of the way.)
Note: This is one of those good oppurtunities to replace some other shit. The valve cover breather line and the vacuum line to the FPR are both prone to get old and brittle and break causing vacuum leaks.
4. Unplug the coolant temp sender for the cluster (brown connector) and the coolant temp sensor for the ecu (blue connector). A nice long flatblade can make it easier to push the clips.
Note: This is a good chance to replace your ecu coolant temp sensor. Numerous times this single piece throws people into a furious parts replacing bender. They are cheap and easy to replace. If it is bad your ecu will not meter fuel correctly. Usually itll tell the ecu to run very very rich all the time. If you are installing bigger injectors you want this thing to work right.
5. Unplug the fuel injector harness where it mates to the engine harness. I forget the connector number and I couldnt find a good pic of how to find it so I will describe it as best I can. If you look underneath the intake manifold on the drivers side closer to the firewall side (front to back) down near the middle of the block you will see a bracket with the round connector. The top half is the fuel injector harness and sneaks up under the intake manifold to the fuel injector clips. You need to unlock this harness. It is a round lock. I find it easiest to hold the bottom and twist the lock on the top. One side of this connector also has a plastic retainer nut that holds it into the bracket. You may or may not have to mess with taking the wiring out of the bracket for the note im about to make.
Note: This is a damn good time to check both sides of this connector. This is another one of those things that can cause people major headaches. Often time these connections to the injectors get corroded and can cause some assanine behavior in your car. Now is a good time to thoroughly clean it. I prefer some wurth contact cleaner here.
6. Next you want to remove the injector harness off of the injectors themselves. Now this rail is clipped onto each individual injector. As Ive noted with circles the clips are around each one and you can go to the trouble of trying to get each clip off or cocked 90 degrees. Thats the hard way though. I prefer to grab the harness plastic at the front end and pull up firmly. This should unclip the front half. The grab the rear and do the same. Once the harness is completely free from the injectors just sneak it out being careful to sneak the tail with the round plug up under the intake manifold. Remember how everything went.
7. Now that the harness is out of the way you can remove the fuel lines from the fuel pressure regulator. REMEMBER WHICH WAY THESE LINES ARE CONNECTED FROM TOP TO BOTTOM. LABEL THEM IF YOU NEED TO. One is the feed and the return. Another major headache causer is to hook these up backwards. I did not have a good pic of the far side of the fpr with the lines but i circled it three times so you know to look here for fuel lines.
Once those are disconnected simply remove the four bolts holding the fuel rail to the intake manifold.
Note: If your feeling up to a more involved task you can now take this as a good time to replace those rubber fuel lines in the engine bay. Its a little more involved but those lines will often get old/brittle/fall aparty.
8. Now you can remove the fuel rail with the injectors. I do the same thing I did with the fuel injector harness. Put your hands under it and firmly lift straight up. If you have OEM injectors they are clipped in and will stay with the rail. If not you may have some injectors stay in the intake. Doesnt matter so long as you grab em out.
9. Here is a fuel rail with Gen 3 bosch injectors installed in it. Note on OEM injectors there are clips that hold the injectors into the rail. These clips are not even necessary as the rail is bolted to the intake manifold. On the bosch gen 3 you wont need the clips at all. Just make sure to bolt the rail back into the car when reinstalling. The Gen 3 are the same length as OEM Gen 1 injectors. Make sure to install new o-rings (or buy injectors from me freshly rebuilt with new o-rings.)
I like to use a little bit of vasoline on the o-rings then pop them into the fuel rail. They should go in fairly easy. Make sure they arent pinched. Some people use motor oil or silicone for this as well. Either will work just try to keep it out of the injector filter basket.
Orient the injectors so that they are facing toward the passenger side of the car to make it easier to get the clips lined up.
Reinstall is simply reverse of this whole procedure with a couple of small notes. First when installing the fuel rail before getting carried away pushing the injectors down into the intake holes make sure they are all started and lined up. Once they are all started into the holes a little firm push on the top of the rail should seat them then your rail bolt holes should line right up.
Also dont forget to replace your valve cover gasket if its been a while and those little half donut seals for the head/vc.