How to change the RB20DET spark plugs - R32 Nissan Skyline GTS-T DIY
RB Motoring
Changing the spark plugs in your RB20DET is an easy job if you've ever turned a wrench. You'll need the following tools:
- A basic socket set (I've had the same Kobalt set for 10 years. I can return anything that breaks to Lowes, no questions asked, and they even replace missing sockets for the price of shipping and handling.)
- Flathead screwdriver
- Long 3/8" extension
- Hex socket set
- Spark Plugs
- Spark plug socket
- Torque wrench
- Anti-seize
All the images below can be expanded by clicking on them.
The spark plugs in the RB20DET are located under the black plate that says NISSAN. To get to it, we need to remove the crossover pipe. It can be done without removing the crossover pipe, but it makes things awkward and cramped, and removing the pipe takes minutes.
Start by loosening the clamps labeled above. Both ends of the intake pipe, both ends of the blowoff valve, and one end of the black hose labeled #5 should be loose when you are finished. Flip the #5 hose out of the way.
The crossover pipe is bolted to the engine with two bolts right above the kink in the crossover pipe (where it says TURBO). Remove those two bolts. There are two more bolts that hold the vacuum hardlines to the crossover pipe. We labeled one in the image above, follow the lines toward the intake plenum to find the other. Once you remove the bolts, you can remove the crossover pipe and attached blowoff valve.
After the crossover pipe is removed, you'll need to remove the black plate covering the spark plugs, and unplug and unbolt the igniter. Start at the front of the engine and work your way back. Using your hex head driver, loosen the 6 bolts labeled in red #1-6 that lead back to the igniter. There are two more of these located under the igniter plugs (#7 and #8). Unplug the igniter plugs, and then remove the 4 bolts holding the igniter in place (yellow #9-12). Once the igniter is removed, unbolt the last two hex head bolts that hold down the cover plate. Remove the cover plate to reveal the spark plug valley.
In the spark plug valley you will see the six coil packs mounted to a metal bracket, plugged in to six brown connectors. Unplug the connectors and then unbolt the coilpacks by the 12mm bolts with 4 etched into the top of them. The coilpack bracket is actually two pieces - pull it away from the head to reveal the plugs. Mine was suctioned in there really tightly, so I had to really wiggle and pull on it. If you can't get it out, wrap a flathead screwdriver with a cloth and use it to pry.
The removed coilpacks.
With the coilpacks removed you can finally access the plugs. Use your long extension and your spark plug socket, and take each plug out. Before installing your new plugs, apply a small dab of anti-seize to the threads. This will keep them from seizing (as the name implies...) and will also make them easier to remove next time. I put anti-seize on pretty much every threaded surface that goes back in the car - just be sure not to get it on the electrode of the spark plug! While the plugs are out, it would also be a good time to run a compression check.
When replacing the plugs, torque them to 20 ft/lbs. Put everything back on in opposite order, and start your car up!