TeeMuumi

Created the account just to give my thanks to Kenpachi as that quote from shop manual was the best advice I could find anywhere. Thanks a lot! For some reason there's quite a lot of different and propably misleading tips on this job so here's what I experienced on fifth gen GT with EJ255 (2010 JDM, although spark plug related it should be the same on US and Europe versions) All you need to do was to follow the shop manual quoted by Kenpachi so NO lifting the engine is required and also no need to remove the coil connectors although it is easier when they are not tangling on the way. Also the harness clips of the coils comes off merely prying them out with a flat head screwdriver as they are plastic trimm clip inserts and since they are thight around the wire there's a risk to cut the insulation when cutting the clips. You have enough space for the socket extensions when you have removed the battery and the air cleaner box out of the way, you just need to have some patience and finger agility to install the socket and joint extension separately for the #3 and #4 plugs. After removing the air box it should be noted that the intake hose goes straight down the TC so the hose should be plugged with a rag or something similar to avoid anything dropping down to the intake. For the socket extensions I would recommend approximately 10" or 25cm length and two extensions to make it easier. Since you need to use the joint/swivel extension I would recommend to wiggle the ratchet when unscrewing to avoid any jamming of the socket or joint which could lead to breaking something. And when installing the plugs a torque wrench should be used to make sure of the correct thightness as the feel of the wrench is different with joint extension. Last thing worth noting is that my hands are somewhat small, glovesize 8 and the space around #3 and #4 was tight for me also so I wouldn't recommend this job if you have hand size above 9. To give a short guide, here's what I did: - Remove the battery, 10mm nuts on connectors and bracket. - Remove the air filter box, 2x 10mm nuts, 8mm hose clamp and maf connector. -- seal the intake hose with a rag or something similar. - Unscrew the 12mm bolts holding the coil packs, pry the plastic trim clip out. - Pull the coils out, #3 and #4 you have to turn the pack approximately 180deg due to the L shape of the bracket for the 12mm bolts and tight space further back. - Insert the spark plug socket together with the joint extension first for the #3 and #4 plugs then it's easier to plug in the extension(s) (of course this depens on the tools you have) - Install plugs with socket and joint extension screwing them by hand and tightening them with a torque wrench. - Install all back in (don't forget the rag!) The plugs according to the JDM service manual are as follows: 2.5i SIFR6A11 gap: 1.0-1.1 mm 2.5GT SILFR6B8 gap 0.7-0.8 mm 3.6R SILFR6C11 gap 1.0-1.1 mm Replacement interval 100.000km (if I read it correctly) I used ILFR6B8 which doesn't have the projected square tip electrode as the SILFR6B8 but they seem to work just fine. I guess that's it. As a disclaimer these are just my experiences and tips, not necessarily suitable for your situation. Cheers!