These are the parts and part numbers needed to replace the Intake Manifold gaskets. These are for the 3.1 six cylinder engine.
25043843 - PCV Valve
10189205 - Seal
24507583 - Thermostat
12480824 - Gasket Kit
89017117 - Gasket Kit
24504709 - Seal
You will need coolant as well. I recommend picking it up after market as it is over $20 from Chevy.
1) Take your time especially if this is the first time. A manual is also useful
2) Label wires as you remove them
3) Raise the engine and remove the RH motor mount to move the power steering pump out of the way.
4) When disconnecting the fuel line from the rail be very careful not to lose the green o-ring
5) Pull the intake manifold followed by removing the push rods and rotating rocker arms
6) Stand the push rods in a box the same way they came out. I use a screwdriver and punch 12 holes in an old box. Make sure you write on the box cyl. 1, front of car etc. It is extremely important that you do not mix them up.
7) Clean all gasket surfaces properly.
8) Use pipe dope on your intake bolts. I also added serviceable loctite.
9) Torque all bolts to the new GM specs. See below
10) Oil the fuel injector o-rings when reinstalling and make sure they are properly seated.
11) Change your plugs, wires, belt and thermostat now that you have full access to all these things.
I pulled this document from the forum a while back…..not sure who originally posted it.
Document ID# 1396678
2003 Chevrolet Malibu
Engine Oil or Coolant Leak (Install New Intake Manifold Gasket) #03-06-01-010B - (10/24/2003)
Engine Oil or Coolant Leak (Install New Intake Manifold Gasket)
2000-2003 Buick Century
2002-2003 Buick Rendezvous
1996 Chevrolet Lumina APV
1997-2003 Chevrolet Venture
1999-2001 Chevrolet Lumina
1999-2003 Chevrolet Malibu, Monte Carlo
2000-2003 Chevrolet Impala
1996-2003 Oldsmobile Silhouette
1999 Oldsmobile Cutlass
1999-2003 Oldsmobile Alero
1996-1999 Pontiac Trans Sport
1999-2003 Pontiac Grand Am, Montana
2000-2003 Pontiac Grand Prix
2001-2003 Pontiac Aztek
with 3.1L or 3.4L V-6 Engine (VINs J, E - RPOs LG8, LA1)
This bulletin is being revised to change the model Information. Please discard Corporate Bulletin Number 03-06-01-010A (Section 06 - Engine).
Some owners may comment on an apparent oil or coolant leak. Additionally, the comments may range from spots on the driveway to having to add fluids.
Intake manifold may be leaking allowing coolant, oil or both to leak from the engine.
Install a new design intake manifold gasket. The material used in the gasket has been changed in order to improve the sealing qualities of the gasket. When replacing the gasket, the intake manifold bolts must also be replaced and torqued to a revised specification. The new bolts will come with a pre-applied thread locker on them.
An oil leak may result if the vertical bolts are not tightened before the diagonal bolts.
Diagonal bolts may require a crows foot to tighten.
Tighten the vertical lower intake manifold bolts (1) to 7N•m (62 lb in).
Tighten the diagonal lower intake manifold bolts (2) to 7N•m(62 lb in).
Tighten the vertical lower intake manifold bolts (1) to 13N•m(115 lb in).
Tighten the diagonal lower intake manifold bolts (2) to 25N•m(18 lb ft).
Intake manifold Gasket
Intake manifold bolt - short
Intake manifold bolt - long
Parts are currently available from GMSPO.
For vehicles repaired under warranty, use:
Manifold or Gasket, Intake (Upper, Lower) - Replace Gasket Lower
Use Published Labor Time