Well I am up here in Virginia for a little while and it's been pretty cold. The past few days my idle has been very low and I knew my original intake gasket had run its course (104k is alright with me).
So I headed over to Priority Toyota and spent around 7 bucks and change and got a new 17171-22060 intake gasket.
This DIY will work for 2003-2004 models but you a few steps would be different mostly centered around the throttle body and an extra bracket on the intake manifold connecting to the throttle body.
So let's begin the DIY.
Disclaimer: Myself or ToyotaNation are not responsible for any damage or injury that may result from use of this DIY. All vehicles should be diagnosed and repaired by qualified technicians. Proceed with this DIY at your own risk.
3/8 drive ratchet
3/8 drive extensions (3 in, 6 in, 9 in)
3/8 drive 10mm socket
3/8 drive 12mm socket
3/8 drive torque wrench (optional I didn't use it)
Rags (new clean rags preferred)
Throttle body cleaner (if cleaning throttle body)
2 M6 x 1.0 Bolts to replace the plastic clips securing the engine cover (if needed)
Here we go.
1. Secure parking brake and then secure hood in open position.
2. Remove the engine cover. Remove the 10mm nut, loosen the 10mm stud nut, and remove the two plastic clips if you have them and remove the engine cover.
Note: The two rear plastic clips regularly get lost/break. I replaced mine with two M6x1.25 bolts with a 10mm head. Much nicer.
3. Remove and set aside the air cleaner and hose. Loosen the 10mm hose clamp for the throttle body and remove the PCV breather hose by pulling it straight off. It should come right off, but if it doesn't press the clamp and lower it on the hose and use hose pliers to twist off the hose. Unclip the air box lid and set the air box with PCV and intake hose to the side.
4. Remove the vacuum and breather hoses from the top of the intake manifold by pulling them straight off. They should come right off, but if they don't press the clamp and lower/raise (depending on perspective) it on the hose and use hose pliers to twist off the hose.
5. Remove the electronic throttle body connector. Push the center connector release and pull off the connector.
6. Remove the throttle body. Remove the 2 10mm nuts and 2 10mm bolts and pull off the throttle body. Route the cooling lines away from the studs and hang the throttle body.
7. Remove the intake manifold wiring harness clip. Using your screwdriver release the catch and remove wiring harness clip from above the alternator.
8. Remove the intake manifold bolts. Remove the bolt the 1 12mm near the bottom of the intake, 2 12mm bolts on the bracket located on the right side of the intake, 2 12mm nuts holding the wiring harness retainers, and 2 remaining 12mm bolts from the intake manifold. Remember where each bolt/nut came from.
9. Remove the wiring harness from the intake manifold by pulling back the two wiring harness retainers (from around the nuts), flipping them around and moving the wiring harness out of the way.
10. Remove the intake manifold by pulling it back and out off the studs.
When removing take note of the hidden vacuum line behind the intake and remove it.
11. Remove the factory intake gasket.
This is what caused the whole issue.
12. Using your brake clean and rag clean the face of the intake manifold and cylinder head.
13. Install the new intake gasket. Make sure the indents line up and seat the gasket flush with the manifold.
14. Install the intake manifold on the cylinder head. Reinstall the two wiring harness retainers around the studs, and on the clip above the alternator. Install all the 12mm bolts and nuts in the proper areas.
Don't forget the hidden vacuum line behind the intake manifold from the removal procedure. Be sure to install it now.
I installed all bolts and nuts hand tight with my ratchet but have done around a bunch and never had an issue. This is my personal car too. Torque spec is 22 lb ft.
15. Clean the throttle body and reinstall or just reinstall the throttle body by installing the 10mm nuts and bolts. Follow this DIY to clean the throttle body:
Note: Remember to route the cooling hoses around any dipsticks or studs that may get in the way.
16. Reinstall the two vacuum lines on top of the throttle body.
Note: Make sure the hose retainer clips are in the proper position.
17. Reinstall the air cleaner assembly and PCV breather hose.
Note: Make sure the hose retainer clip is in the proper position.
18. Reinstall the engine cover.
Note: If you lost/broke your clips install your new M6 x 1.25 bolts now.
19. Start the engine and verify you have no vacuum leaks. And it idles properly.
20. Be amazed at your work.
Hope this helps. My car idles like new again.