Another EGR thread

To start off, I just got this car and successfully fixed the brake booster failure. Now sonce Ive been driving it all the real problems have been coning out of the woodwork. I diagnosed it down to the puddle of oil in the intake manifold. Ive researched enough to know this is a known problem. The symptoms were knocking and shaking at 50% power and 20-30mph with mild shaking at higher speeds. No coolant or oil loss that I can detect from 300 miles of driving.

So I have already:

1. Removed the intake manifold, throttle body, and EGR components.

2. EGR was definitely on its way to becoming fully clogged. The pipe had a significant amount in it as well. The EGR cooler was brake cleanered down with 2 cans and a pressure wash in between. It looks damn close to new now with significantly more light and air oassing through after cleaning, yes I tested both air and light passage. No abrasive scrubbing was used in the EGR.

3. Cylinder ports were brushed out and vacuumed to the best of my ability. Bottom line they are cleaner than before but definitely not perfect. Walnut blasting woukd be preferred but its whatever.

Still yet to accomplish in the coming days:

1. Brand new intake manifold coming in the mail, non-OEM but supposedly is redesigned. Hopefully it helps. I have researched the differences between the manifold part numbers visually. If I find it to be modeled after the revised *54 part number ill use it if not ill just clean the original to the best of my ability and use it.

2. Spark plugs, replacing them with new NGK rhutheniums. Yes they are fancy, I run them in my Yaris. They should allow a more complete burn (manufacturer claim). Upon inspection they are as cooked as the rest of the intake components.

3. Oil catch can. This is from what ive read the most effective method of combating this design flaw. Coming in the mail soon.

4. Software update for the EGR valve control. supposedly there was a TSB for the intake manifold that this accompanied. I read it mitigates the opening of the EGR to diminish the carbon buildup including the baffling system in the redesigned intake manifold. Maybe Toyota will do it for free if the TSB is valid. Hopefully they dont decline when they see my catch can .

Things up for discussion:

1. Intake manifold redesign. The new design is not conducive to enhanced performance and in fact the baffles probably make it worse. If i can source some other performance intake mods that are budget friendly it would be appreciated. Something to help compensate any performance loss. Maybe MPG increase, IDK. Its still prius slow, im jn it for the MPGs ⛽.

2. This is a 2012, so early design issues are a common theme. Im totally fine with replacing a motor when it comes time, if the community agrees a late year gen 3 donor would do right? When the piston rings inevitably fail.

 

I just had an excellent idea to throw around here...what if I helad an exhaust shop relocate the EGR exit on the exhaust side to be after the Catalytic converter, like how it is on the Gen 4? Would that further reduce the problem or introduce new problems such as EGR exhaust temp and CELs?

 

197k miles

 

How will I know if its a head gasket?

 

Is there a thread for this mod?

 

I have an endoscope, the spark plugs are out, seems like a fine time to dive in there and see what it looks like.

 

It knocked real good for a few seconds on a cold start once when I bought it and hasnt at all since then. But the conditions I described in the first post are still there. If there is a head gasket leak its very small as I have not noticed any coolant leak. This was all with 300 miles of highway driving around 70mph. I had it in ECO mode and tried my hardest not to push the motor too hard on the throttle.