Clean EGR Manifold, Pipe, Replaced Fuel Injectors, Still Shudder

Hello All!

Thanks in advance for any Advice. Replaced all Spark Plugs and Engine Coils. Did a Thorough Manifold Cleaning, and Pipe Cleaning (Gas Mileage jumped by 180 mi/tank).

Replaced all fuel injectors carefully (Used engine grease and Dialectric grease). I didn't replaced the Orange gaskets that the fuel injectors sit in on the engine side.

Took Prius out for a Spin, still shuddering at low speeds. Is this just aerated fuel working its way out of the system? No codes were yet triggered.

Thoughts? Should I replace the engine O rings that the fuel injectors sit in?

 

Great Questions. 245K. No evidence as of yet. Just refilled the Tranny Fluid, and holding the level, plus changed oil and no evidence of discoloration, and never has overheated. I did Clean the 4 passages and the Manifold VERY thoroughly.

After the Manifold Cleaning, I got a 4th Cylinder Misfire Code--Cleaned all 4 injectors while I waited for the new injectors to arrive. I got a "Multiple Cylinder Misfire" Code after the cleaning, after running great for about 20minutes.

I installed the new injectors last night, 30sec shudder upon starting, then ran phenomenally for about 10 minutes, before the shudder started to slowly return. No Codes Yet.

 

THANKS FOR the advice. I'll check out the EGR Cooler cleaning info you have on your links.

 

Thanks a lot for the "heads" up. I'll follow your instruction for the egr cooler and valve and we'll go from there.

 

Hey Everyone,

Replaced the EGR Valve. Cleaned the EGR Cooler Thoroughly. When I unplug the EGR System Car runs well, once replugged in still shuddering very badly when I accelerate. Thoughts?

 

I've reopened the EGR Manifold and ReCleaned it. Missed quite a bit. Those four little holes were packed solid, I'm ashamed/relieved to admit. Also swapped out PCV Valve while I was down there.
Glad to have learned everything I learned, including being able to take off and clean EGR Valve and Cooler. All of this stuff seemed COMPLETELY OVERWHELMING at first, but I feel so much more able and connected to my prius now.

I'll let you know how it runs tmoro. Thanks for all of the assistance.

 

She's Running Great now. If anything else pops up, I'll log back in!! Thanks for all of your help!