intake manifold removal/stripped bolt argh!

[4orRunner]

So I am still trying to resolve P0401 that is tripping the CEL on my girls 2000 4runner.
The truck has the 2.7 4 cylinder with just under 126k miles.

I pulled the lines off of the EGR valve and gave em a suck (err um vacuum). There is a noticeable drop in idle when there is vacuum on the line but I have heard that the engine should stumble considerably or even die. I am still not sure if the valve is working 100% so I decided to just remove it in order to take a look at it as well as the passages in the plenum.

At first I thought I could remove the EGR valve at the back of the intake, that is when I realized I would have to remove the air box, throttle body, and intake in order to get to the valve. I removed everything without issue until I found a bolt at the bottom of the intake manifold that was rounded bad enough that the 12mm socket could not get enough bite to remove it.

I got underneath the truck to realize that it actually appears to be a brace for the intake as a bar runs from it into the frame. I am only trying to remove the top half of the plenum so I can take a look at the EGR passages and clean if necessary.

Does anybody know how many bolts are actually holding the top half of the plenum to the bottom half? I took out all of the other bolts and the thing would not budge. Unfortunately I believe the previously mentioned bolt to be what is holding me up.

I wasn't sure what the best method would be to remove it being that is in such a tight space and wasn't really sure if it was even necessary. Unfortunately, it was getting dark out so I decided to put all of the bolts back in and continue another day.

Any help is much appreciated!

 

[Yotaoffroad27]

Are you 100% sure you have to pull the intake to remove the EGR valve? I was pretty sure you don't?

 

[4orRunner]

Are you 100% sure you have to pull the intake to remove the EGR valve? I was pretty sure you don't?

I tried to remove the valve itself but the studs sticking out of engine combined with the pipe just behind the valve make it impossible. It is literally stuck in between the two parts.

I assumed I would have to remove the plenum to get to the EGR port inside of it anyways.

 

[Yotaoffroad27]

I tried to remove the valve itself but the studs sticking out of engine combined with the pipe just behind the valve make it impossible. It is literally stuck in between the two parts.

I assumed I would have to remove the plenum to get to the EGR port inside of it anyways.

I always removed the pipe... 2 nuts on the EGR valve, 2 nuts on the manifold, and 1 or 2 supports across the back of the head. I removed the EGR on my 2rz (2.4L 5lug Tacoma 4cyl, the 2rz and 3rz is the same intake).

 

[4orRunner]

I always removed the pipe... 2 nuts on the EGR valve, 2 nuts on the manifold, and 1 or 2 supports across the back of the head. I removed the EGR on my 2rz (2.4L 5lug Tacoma 4cyl, the 2rz and 3rz is the same intake).

Hmm... I'll have to take another look at it. Maybe there was a way to remove the pipe that I didn't notice. I will still have to find a way to remove that support on the intake to get it apart to check if the passage is blocked.

 

[4orRunner]

Just thought I would follow up real quick.

I managed to get the stripped intake brace bolt out and was able to pull everything off to take a look.

EGR valve and VSV checked out fine. The EGR port inside the plenum however was completely packed with carbon from beginning to end.

after about 10 minutes of work with a can of carb cleaner and a large screw driver the passage was clear again.

I reinstalled everything back on the truck and fired it up.

After letting it idle for 5 - 10 min I pulled the vacuum line off the top of the EGR valve and gave it a suck. The truck bogged and died almost instantly where as before it only made the idle drop a tiny bit.

I cleared the CEL with my obd reader and am hopeful that the problem is now resolved.