P0402 Code - removing the throttle body

[dparnas]

I've been getting the P0402 code frequently lately with this cold weather. Rig is running great, so not concerned about it at all. Never comes on when the car is warm. I think I'm going to take off the throttle body and try and clean out the fitting that I saw on this thread that gets clogged with carbon and check all the other hoses. Anything I should know before taking the throttle body off? P0402 - Learn from my mistake - https://forum.ih8mud.com/threads/p0402-learn-from-my-mistake.132135/

 

[Rusty Marlin]

I find the bottom two TB bolts are most easy attacked with a LONNNGGGGG extension standing next the passenger fender.
When reassembling, that's a good time to reset the slack/tension in the three cables.
Check all the vacuum lines for cracks.
When leaning over the engine from the front, be aware of the nipple in the top radiator cap, its wicked easy to set your hand on it.
Be gentle with the various electronics' plug clips.

If you pull the top half of the intake manifold too, you're going to need or at least want a 36" extension with a little wobble adaptor and reach most of the fasteners from underneath and a good flashlight will help you find the sneaky little boogers.

 

[dparnas]

I find the bottom two TB bolts are most easy attacked with a LONNNGGGGG extension standing next the passenger fender.
When reassembling, that's a good time to reset the slack/tension in the three cables.
Check all the vacuum lines for cracks.
When leaning over the engine from the front, be aware of the nipple in the top radiator cap, its wicked easy to set your hand on it.
Be gentle with the various electronics' plug clips.

If you pull the top half of the intake manifold too, you're going to need or at least want a 36" extension with a little wobble adaptor and reach most of the fasteners from underneath and a good flashlight will help you find the sneaky little boogers.

Great, thanks so much! Not planning to remove the intake manifold. If I can't get the result I want with the TB off, I'll probably punt to the local shop. I just don't have that much time. I'm not overly concerned since the car is running so well. But figure it's worth a shot.

 

[Noahrob]

I had this for a long time, took of the intake, cleaned everything with a wire frayed at the end (like a chimney sweep) and still had the code. Took off the intake a second time, replaced all the little vacuum lines and then zip tied them to make sure they were tight. The combination of using the pipe cleaner, new lines and zip ties got rid of the code. It has been 2+ years, no issue.

If you're in there, might want to go ahead and replace the fuel filter at the same time.

 

[Kernal]

As mentioned above, check/replace all the vacuum lines, any of the smaller 3.5mm original hoses that you pull off should be replaced as they tend not to seal well once that rubber-to-metal "stiction" seal is broken IME.

Toyota sells bulk 3.5mm vacuum hose that you can cut to fit (90999-92003)

Or go here:

OEM Vacuum Hose Kit- 3.5mm

OEM Vacuum Hose Kit- 3.5mm (VHK-1)

absolute-wits-end.com

There's also a thicker formed hose that runs from the EGR valve to the vacuum modulator and a ~ 5" length of fuel rated hose that runs from the top of the Throttle body to a pipe. If original that straight fuel hose will be rock hard and IME the only way to remove it is to cut it off. That original hose is no longer avialble in the exact length but Toyota sells a longer section of the correct type hose that you cut to fit (95337-06020)

 

[dparnas]

As mentioned above, check/replace all the vacuum lines, any of the smaller 3.5mm original hoses that you pull off should be replaced as they tend not to seal well once that rubber-to-metal "stiction" seal is broken IME.

Toyota sells bulk 3.5mm vacuum hose that you can cut to fit (90999-92003)

Or go here:

OEM Vacuum Hose Kit- 3.5mm

OEM Vacuum Hose Kit- 3.5mm (VHK-1)

absolute-wits-end.com

There's also a thicker formed hose that runs from the EGR valve to the vacuum modulator and a ~ 5" length of fuel rated hose that runs from the top of the Throttle body to a pipe. If original that straight fuel hose will be rock hard and IME the only way to remove it is to cut it off. That original hose is no longer avialble in the exact length but Toyota sells a longer section of the correct type hose that you cut to fit (95337-06020)

Awesome!! Thank you.

 

[Kernal]

The formed hose running from the EGR valve to the vacuum modulator has a separate number, don't have it off hand.

Try searching toyotapartsdeal maybe, their website usually lists the smaller parts. Or, go to Partsouq and enter your VIN and look for it there.

 

[67cruiser]

I had this for a long time, took of the intake, cleaned everything with a wire frayed at the end (like a chimney sweep) and still had the code. Took off the intake a second time, replaced all the little vacuum lines and then zip tied them to make sure they were tight. The combination of using the pipe cleaner, new lines and zip ties got rid of the code. It has been 2+ years, no issue.

If you're in there, might want to go ahead and replace the fuel filter at the same time.

The fuel filter is a JERK