My rig has 82k miles on it, and probably has never seen a tune-up; I bought from a dealership at about 65k miles, so it was probably a lease return. I have not pulled the plugs to find out how bad they are but lately I've been noticing a dramatic decline in mileage and a bit less performance, so I'm going to have a "fix the rig" day and just freshen everything up. Here is a list of all planned, however if anyone has cheap or minor (hopefully both, but I'm not opposed to wrenching as long as it isn't expensive parts-wise) recommendations for things I can also do, please add them!

- New spark plugs, Toyota recommended (dual-tip I believe?)
- New PCV
- Check-out vacuum system, may replace hoses. At 82k some might be cracked on the ends now.
- Thoroughly clean out Throttle Body with carb cleaner and toothbrush. ***DO I NEED TO REMOVE FROM INTAKE FOR THIS, AND IF SO DO I NEED TO RPLC GASKETS?
- Verify condition of other hoses, lines, etc. Replace as necessary.
- Belts all look ok, no need to touch them yet.
- New fuel filter
- Air filter is K&N, recently cleaned (excess oil wiped to protect MAF). Replacing with Amsoil soon anyway, but I do not believe this is the problem.

I have also noticed a very sporadic idle issue where it will drop to about 300RPM and stumble a bit, but touching the gas acts normal (i.e. not a missing plug). Could this be a dirty throttle body, some issue with vacuum system (or PCV), or ??

Thanks for the input!

 

- New spark plugs, Toyota recommended (dual-tip I believe?)

Good idea.

- New PCV

Its very rare that these need replacing. You should be able to clean it out with the carb cleaner and a little shaking until it sounds "loose"

- Check-out vacuum system, may replace hoses. At 82k some might be cracked on the ends now.

Good idea

- Thoroughly clean out Throttle Body with carb cleaner and toothbrush. ***DO I NEED TO REMOVE FROM INTAKE FOR THIS, AND IF SO DO I NEED TO RPLC GASKETS?

Be careful with the carb cleaner. I would spray it on a clean towel and go around and around the TB until its clean. No you do not need to pull the TB off, and if you did you would want to replace the gaskets.

- Verify condition of other hoses, lines, etc. Replace as necessary.

Good idea

- Belts all look ok, no need to touch them yet.

Good thinking, but the only way to really tell if they are ok is to pull them, so you might as well do them while you are in there.

- New fuel filter

Never done this one. I thought it was an in tank filter...

- Air filter is K&N, recently cleaned (excess oil wiped to protect MAF). Replacing with Amsoil soon anyway, but I do not believe this is the problem.

Definetly get an Amsoil!

I have also noticed a very sporadic idle issue where it will drop to about 300RPM and stumble a bit, but touching the gas acts normal (i.e. not a missing plug). Could this be a dirty throttle body, some issue with vacuum system (or PCV), or ??

See if its still there when you are done with all this work.

 

I would not use carb cleaner for cleaning the throttle body, you should be able to find fuel injection cleaner at your local auto parts store.

You can pull the TB off not problem, just make sure you do not undo the two hoses underneath it that have clips on them, they route coolant through the TB to warm it up. If you do remove it, you do not need a new gasket, it's metal and is infinitely reusable. In fact I would recommend removing it so you can clean it better because the back of the butterfly is what gets very dirty.


Good luck