I'd recommend replacing the wires when you do it to save on trouble later.
At least that's what I do with customers that must pay for my labor. I
also always replace the plenum gasket, but you could probably re-use it
with no problem. I'd expect cost to be about $15 to $20 at the dealer.
Here's what I do:
Remove the engine cover.
Remove the top of the air box and air intake hose.
Unplug the throttle position sensor and idle actuator. Also unplug the
air temp sensor at the back of the intake.
Remove the vacuum hose to the fuel pressure regulator.
Take the pcv hose out of its holder.
Remove the injector harness connector from the holding tab and unplug the
Unbolt the ground strap from the back of the intake.
Unbolt the bracket holding the throttle cables.
Remove the three 12mm head bolts holding the back of the plenum.
Remove the five 12mm head bolts and two 12mm nuts from the front of the
Lift the plenum up and off, and stand it up on the throttle body side.
Getting it up and off the studs will require a combination of finesse and
force. By tilting it up, you won't need to remove the coolant hoses and
won't have to add coolant and make sure you've burped the system.
DON'T DROP ANYTHING INTO THE ENGINE. Cover the holes if you have any
Reassembly is pretty much the reverse of disassembly. You'll want to
start all the plenum bolts/nuts before tightening any of them. If you
tighten the front ones prior to installing the back ones, you'll have