i just replaced the plugs on my 2007 Ford five hundred...not quite like swapping plugs on an old 5.0L but not impossible either...first, if you are not ready to take your intake manifold off, take it to a shop...second make sure you have the right tools...something specific is the T-20 torx bit you'll need to pull off a "valve" on top of the manifold just after the throttle body...
i removed the upper airbox, air intake tube and disconnected the hoses attached to it...careful with the mass air sensor connector clip...
then i disconnected everything attached to the manifold and throttle body...
hoses(i'd say about 5 or so)
wires
throttle body motor clip
then remove the bolt between the 2 torque arms that are attached at the engine and one at the strut tower brace...the top arm will swivel to the side so you can reach behind the manifold...
there is a double vacuum hose grommet that needs to be removed to access one of the EGR valve attachment bolts...
the hardest part for me was accessing the three 5/16" bolts that attach the EGR valve to the manifold...in the back behind the area just after the throttle body...you can loosen them and finger them out the rest of the way...you can reach 2 of them from under the throttle body with a 12pt combination wrench(don't drop it)...the other one i used a 1/4" socket wrench with a short extension(5/16" socket)...in hindsight i would have tied the wrench to my wrist just in case i lost any grip...
after that, it's on to the manifold...there are 8 bolts that go all the way to the heads and there are 4 smaller screws(3/16" i think) that attach the upper intake manifold to the lower intake manifold...the fuel rail is attached to the lower intake manifold which stays behind...you won't be able to take off the whole lower assembly because of the fuel rail...
wiggle the upper intake manifold and just lift it out of the way...i did not completely remove the manifold...there are still a couple things still attached to the manifold...just move it enough to where you can access the rear bank...
remove the coil-on-plug retaining bolt...pull the boot...pull the spark plug...install new spark plug(don't forget anti-seize)...repeat for all six...compare old and new plugs and make sure you have the right plugs...seems like an obvious thing, but I've met some crazy people...
now reverse the order to put it all back together...i did this in my driveway in about 3hrs...i did not use any manual, just some simple mechanical knowledge...if it seems too complicated, then it probably is and you should rethink the notion of even attempting this...i think i covered everything you'll need to know...just don't break anything...
good luck...
I would replace the spark plugs after 50K, the wires and plugs again at 100K.
on the 3.5 v6 take off the engine cover, unscrew the coilpacks and take out the spark plugs.
Changing spark plugs is relatively easy. Disconnect the batter and spark plug cables, and remove the old spark plugs. Next replace the spark plugs with new ones, reconnect the spark plug cables and battery.
After 105,000 miles. Nissan Maxima spark plugs are platinum-tipped and lasts for many years.
Take it to a Toyota dealership
How to change the spark plugs
get a 3/8 in.drive Rachet,w/a 10in.3/8 extension,plus your spark plug Socket.that will do it!
u take the old ones out and replace them by color
NGK platinum plugs
Both V6 engines have 6 spark plugs
yes - 8 spark plugs for a gas V8 engine
( 6 ) spark plugs