remove throttle linkage, all wires to sensors, etc., there is probably a bracket on backside that you have to unbolt also. then remove all the bolts in top of plenum. lift up and out, making note if there is any vacuum hoses on the underside. you need to replace the plenum gasket before re-installing.
You have to remove the upper intake plenum.
The rear spark plugs are covered by the intake manifold plenum which must be removed to access the plugs.
You have to remove the intake plenum to access.
Remove plenum at front top of engine for access Coils (each cylinder has its own) sit on top of spark plugs - remove for access
First of all you can get to the first 3 plugs very easily. The other three you have to take off the plenum (be sure to replace the old plenum gasket)
You have yo remove the intake manifold(plenum),Go to your local auto parts store and get a haines manual.It will describe everything in detail.
The upper intake plenum must be removed in order to gain access to the rear plugs (#1,2 & 3). It's not too hard a job to remove. About an hour or less.
you must remove upper intake manifold to access these plugs
Depends on year and model mine is the estima aeras 2000 v6 1fe az front three plugs are easy but you have remove the plenum to access the three rear plugs as they are impossible to get at
I access them from underneath, other people remove the wiper cowl and intake plenum.
remove upper intake plenum
You have to remove the upper intake manifold.