Direct Injector Plug Installation
Our direct injector plugs are a press-fit design that is removeable by use of a slide hammer. Each kit comes with 6 plugs, 6 bolts and 6 retention plates. The bolts are used to fix the retention plates to the top of each plug. The retention plates allow the stock fuel injector hold-down bracket to be used with our plugs.
Start by removing all fuel injectors and fuel rails. Using a nylon brush clean the injector bores to remove any dirt/particles. Once cleaned thread one of the bolts into the top of a plug and leave a couple millimeters of thread showing (like below). This will help keep the driver centered on the plug when installing.
Place an appropriate sized driver or a 14mm socket on top of the plug. The driver/socket should not be pushing on the bolt, the bolt head should be inside the driver/socket. Using a hammer with light/moderate force, tap the plug into the direct injector bore. Listen for an audible sound change as the plug bottoms out, this will be obvious. Note that it doesn’t take a lot of force for the plug to seal the chamber.
If the plug requires no force to install then the injector bore has been ovaled and damaged. In this case you will need to repair the injector bore with a repair kit or by replacing the cylinder head.
Finally remove the bolt from the plug, add a couple drops of blue loctite to the threads and install the retention plate onto the plug. Be careful when tightening to keep the retention plate straight to avoid contacting the valve cover. Tighten the bolt to 3-5nm, if the plug spins while tightening, stop tightening and move to the next cylinder.
The interference fit is very small as it is only sealing the combustion chamber. The stock fuel injector hold-down brackets keep the plugs in the head just like the factory fuel injectors.
Repeat these steps for all cylinders and reinstall the stock fuel injector hold-down brackets.