[Air Surge Plenum] Air Control Valve Issues?

Alright, still going to go through the testing I found from an FJ manual, but thought I’d share some info on the mysterious freggin black valve on the rear of the air surge plenum that doesn’t seem to be intentionally serviceable/replaceable.

It’s called the air control valve, from a third gen post I learned that the servo driven version for the 2gr engines is responsible for altering the path length of the airways to certain cylinders under certain conditions.

For the 1GR I can only assume it does the same and try Toyota’s tests.

Has anyone had issues with these on the 1GR (or replaced the air surge plenum entirely to resolve issues)? If so, what did you experience and how did you solve it?

https://fjcruiserhub.com/docs/1GR-FE-Intake.pdf

 

Personally have not heard or ever seen this piece fail, that being said anything is possible. The issue in terms for repair is that lower half of the main actuator housing (the part that contains the diaphragm/spring) is molded into the plenum. I would just look for a used plenum assembly on eBay if it was no longer operational. It's just a simple wastegate actuator, it'll only fail if it's leaking or the pivot points for the flap/arm are sticking for some reason.

You would probably be just find running it in its "open" position all the time. That flap is really there just to help the air/fuel mix at low rpm. Not sure what amount of vacuum sends the flap to full open but i'd be willing to bet its not far off the 18-20 inHg you would find on a healthy engine at idle.

 

Interesting. Thanks for the feedback/knowledge!

 

Toyota calls it Acoustic Control Intake System (AICS), it changes the effective length of the intake manifold runners to maximize power and efficiency throughout the entire RPM range. When it opens/closes can be changed in tuning, there was quite a bit of discussion about it in the HPTuners thread at one point.

I have never heard of one failing on a Tacoma, it isn't monitored so even it did break or get stuck you probably wouldn't know it.

 

Interesting…. Need to test this out!

 

Or find a wonderfully curious and awesome person who took literal dyno’s showing this thing locked in position a and position b..

Thanks @torpsd!

https://www.tacomaworld.com/threads/flappers-in-1grfe-intake-manifold.363176/page-2