[VT-VX] How To Replace Lower Intake Manifold Gaskets VS-VY Ecotec

[aussieakito]

Once again doing a backyarder, thought i would make yet ANOTHER "how to"

I take the plenum and top manifold off FIRST, this is NOT required but i like to do it this way so i am able to clean the inside of the manifolds and feel satisfied with my job.
All stated 10mm bolts are actually 3/8

Things you will need
-Lim Gasket
-Plenum Seal
-Heater hose "o" rings
-Lim Gaskets
-Engine sealant
-Coolant

First of all remove the engine cover and disconnect the Negative cable on the battery.
On top of the plenum there is eight 5mm allen key bolts that need to be removed

Then remove the plenum lid. If you have never done this you will notice A LOT of gunk build up inside, this is the reason i like to take it apart this way.
Also take note of the seal under the lid, we will replace this once everything is cleaned.

Remove the air intake, unplug the MAF and IAT sensors undo the lid of the airbox and remove as one piece

Next remove the throttle body cable, if you have cruise control there will be another cable to remove as well.
These just pop off, Now with a 15mm open ended spanner loosen the throttle body cable and remove it completely.
There is 3 10mm bolts holding on the throttle body cable brackets, undo these and remove the bracket.
Unplug the TPS and IAC

Remove the drive belt and alternator, There is 2 13mm bolts holding the alternator in position and the bracket on top with a 10mm bolt.
Unplug the alternator and remove

Get yourself some fuel line release tools and remove the 3 fuel lines from the firewall.

Undo the five 10mm bolts on top of the intake (these wont pull out so just loosen them as much as you can)
remove the 3 vacuum lines from the rear of the manifold
undo the 2 vacuum lines on the throttle body
undo the hose for the EGR on the side of the manifold, right behind the throttle body (one 10mm)
Remove the entire top of the manifold from the engine

Unplug and remove the coil pack assembly ( 2 bolts underneath)
Drain the coolant
Remove the 2 metal heater pipes
First remove the rubber hoses on one end, undo the three 17mm nuts on the first pipe and pry it off the engine, note the 'o' ring which we will be replacing.
Undo the two 15mm stud/nuts that hold the entire idler pulley mount/second heater pipe.
Pull the second heater pipe out and notice the 'O' Ring on pipe which will also need to be replaced.

Now to remove the lower intake manifold undo the twelve 10mm bolts holding it down
Move harness out of the way
Unclip harness from around the LIM
Remove lim

Clean all surfaces and place lim gaskets, make sure to use engine sealer on all four corners

Place the LIM on top and bolt it down, im sure there is a torque setting and pattern for these bolts but i just tighten them from centre outwards with about 3 passes.

Bolt the rest of the manifold back on the same way you took it off, making sure not to forget any plugs or hoses.
Put a little rubber grease on the end of the injector 'o' rings and make sure their places are clean.

Bolt the alternator bracket, 2 heater pipes and coil packs back on
Re fit the belt and top radiator hose.
Top up the system, bleed out the air.
Check for leaks
job done

 

[aussieakito]

Added the rest.

 

[commodore665]

Good write up kito , whose car is it ?

 

[Immortality]

I like it

You did a nice job cleaning everything up.

Isn't it interesting how clean the inside of the plenum is where the PCV opening is, must be a decent amount of air/oil coming through to keep it clean like that

Just a couple of things I would add.

In your case this isn't necessary as you have given everything a good clean before putting it back together but many don't so I would recommend that the day before doing something like this you clean the LIM and especially around all the injector bosses with a can of engine degreaser.

I would also recommend putting some sealant on the intake bolts before fitting. I believe the factory torque setting is only about 14Nm which means it doesn't take much for em to loosen off as I discovered when I forgot to do it on mine Some people also recommend re-torquing the bolts in a week or 2.

 

[Hertz Donut]

MacGyver tool tip for if you don't have access to fuel line removal tools:

You can cut up the nozzle from a caulking gun cartridge (e.g. Sikaflex) to do the job. Cut the tip down until the opening is slightly wider than the line being disconnected, then cut a slot along the length of the nozzle so you can get it over the line. Push the end of the nozzle along the line into the connector. It should pop right off, and you can move on to assembling a nuclear weapon from a kitchen blender and a stuffed toy.

 

[aussieakito]

Good write up kito , whose car is it ?

This was a backyarder i done
Vy exec


Also i have no idea why some of the pictures have dropped out

 

[MiKExAUS]

thanks for the write up. I'm just about to do the job. Any idea why the pics aren't working?

 

[Immortality]

Maybe they have been removed from the site hosting them?

 

[MiKExAUS]

ofcourse... sorry i didn't read aussie's comment.

Is there a sure way to tell if it is indeed the LIM gasket that has failed? I have a bit of coolant puddling near the rocker cover. a bit of **** was collecting on the radiator cap seals but i did a coolant flush and it hasn't really come back. but the small puddle of coolant appears every now n then...

 

[Immortality]

YEp, most likely LIM gaskets.