Post by
Article Manager »
https://forums.nicoclub.com/article-manager-u7968.html
Wed Jan 21, 2004 2:53 pm
Removing and Replacing the Injector
As you can see in the above picture of the FI only one of the two screws is accessible. There’s an identical screw on the left side that cannot be seen because it is underneath the plenum. This is why a dremel must be used to grind away the plenum to gain access to this screw. By looking at the picture you can tell how corroded these screws can be. This was taken from a 10 year old J30 with 123K miles, mostly garage stored. The screws have softened over time so be careful not to strip them.
1) The first step is to relieve the pressure in the fuel lines. Make sure all or at least 5 (of the six) FI’s and all coil packs are plugged back up. Start the engine then pull the fuel pump fuse. The engine should die on it’s own within seconds. Then shut off the ignition key.
2) To get an idea of how much should be grinded away from the plenum, stick a Phillips screwdriver into the hidden FI screw. Now imagine trying to get this out. Considerable grinding should be realized.
3) Several style bits were used to get this just right. Cylindrical, spherical and cone shaped were all used to make room on my #6 FI. During the process be careful not to grind on the hidden screw as you will need all of it you can to break it free without stripping. After grinding away enough plenum to at least reach the screw try to break it lose and begin unscrewing it. You’ll notice that when backing it out the top will touch the plenum preventing you from completely taking it out. Use this as a gauge to know how much more, and where, to grind on the plenum.
4) To get out that last millimeter of screw it may be beneficial to go ahead and remove the right screw and move the FI brace around until the left screw comes out. This will save a little more grinding.
5) Once the brace is off, use a vacuum cleaner to clean up as many of the grinds that you can. After that I used pressured air and cleaned off the entire plenum.
6) Now that you are ready to pull out the injector soak the injector with Liquid Wrench overnight. Without it, chances are you’ll get nowhere. The next day after a good soak I pulled it out on the first try! Use a good pair of pliers and get a good grip on the red part of the injector. Then pull like hell! I actually ended up using Piston Ring Compressor Pliers to get the FI out because so much of the tip had been broken off the day before.