Is it difficult to replace the 6 platinum spark plugs on a 2002 Infiniti 2002? I imagine the 3 in the front piece of cake but the 3 in the back more difficult. Can anyone speak from experience? I plan to do it this week. Thanks.

In order to do the back three, you'll need to remove the intake plenum. The plenum gasket should be metal so no need to replace unless it's damaged. Most important thing is to make sure that you reconnect every thing you've disconnected and don't lose any nuts/bolts. Good luck!

You may also wish at this time to change the rear 3 coils as well (depending on how many miles are on them), on my 03 Max when I changed the plugs to a step colder I also replaced the coils and installed NWP thermal spacers and upgraded my rear valve cover to the 04 version ( better quality than the 03 version and also less expensive). Just made sense to get everything together as it is a pain removing and reinstalling the intake plenum all the time.

^^^ What Ghost said. Well, except for the coils. Too expensive as a rutine maintanence IMO. I'm willing to bet that you'll find oil in 1 or 2 of the spark plug wells on the rear, (right), bank. The time to replace that faulty valve cover is when you already have the intake off. NWP spacers are a real nice upgrade. I installed mine a couple of months ago when I changed the valve cover and must say that they are worth the price.

Replacing the rear plugs if they have not been changed was what I was referring to, that and because you will be really pissed if a month later after doing the plugs you through a misfire code for one of the rear coils and you now have to remove everything again to gain access. As for oil in one of the chambers it would most likely be #5 (crappy 03 valve cover develop hair line cracks inside) the 6th gen version resolved that issue. Markc have you also done the VIAS delete for a block of plate? very nice little mod you get a very smooth linear pull straight through to red line RPM range.

Only replace the ignition coils if you have reason to do so. I have 5 Infinitis, the oldest are 14 years old and all have original coils.

Thanks guys! The spark plugs going in next week along with new rear brake discs and pads. Then I just have to figure out why the speedometer isn't working and clean up my fuel filler neck to see if it'll correct my EVAP check engine code. Wish me luck =)

If the filler neck is good, you might as well buy an OEM cap (avoid aftermarket cap which may not be a perfect fit). That's what I did in our 97 I30. Of course, I checked all tubings to/from Evap Canister before doing so.

Thanks for the input everyone. Much appreciated =)

Ghost_54 wrote:Replacing the rear plugs if they have not been changed was what I was referring to, that and because you will be really pissed if a month later after doing the plugs you through a misfire code for one of the rear coils and you now have to remove everything again to gain access. As for oil in one of the chambers it would most likely be #5 (crappy 03 valve cover develop hair line cracks inside) the 6th gen version resolved that issue. Markc have you also done the VIAS delete for a block of plate? very nice little mod you get a very smooth linear pull straight through to red line RPM range.

I tried one b4 I had the spacers and Cattman ypipe and didn't like it. So I took it off and sold it. I now have a non NWP plate, ( from someone in competion with NWP). I only bought it from him because shipping was only 5 bucks to Canada. It's a POS. I have to remove the sharp edges from it b4 I install it, and, it's getting cold out. It may not go on till next spring.