Engine shaking at 30-40 mph after lots of EGR cleaning.

Here's a quick synopsis of my issue. My 2012 Prius started using lots of oil. Then I noticed it would occasionally be a little shaking when backing out of the drive way. Eventually, I got a check engine light. I don't recall the exact code but I think it was about the air/fuel mixture. So, I researched a bunch and ended up cleaning the EGR valve, EGR pipe, EGR cooler, intake manifold, and replacing the spark plugs and PCV valve. Just knock it all out at once. But now it seems to shake at around 30-40 mph, which it hadn't done before. I've only driven it once and that was in town so I don't know what it's like at higher speeds. It was shaking pretty roughly for a few seconds the first time I started it after putting it all back together. I don't know if that's relevant or not. I figured it's just loose carbon or some results of removing everything and putting it all back together. Any suggestions?

 

Yes, I just double-checked too. The one at the top of the intake manifold, right? I mostly followed this:

I think I was pretty thorough in checking I reconnected everything. I went back over the video a few times to make sure. The check engine light came on before I ever started any work on it.

 

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Sorry, that's what I meant. I looked it up and it was the one I was thinking. Just described it wrong. I'll have to check the ODO and level. I added coolant after I put everything back.

 

That's kind of what I figured which is why the shaking when I turned it on didn't concern me. I went to the store and back and that's when I noticed the 30-40 mph shaking. Although it isn't consistent. What would be up to spec tightening? I used hand tools, no impacts. I have a tendency to overtighten since I was young, which is something I've had to look out for once adulthood came along. I tightened as hard as I could by hand without getting crazy. If it's something that will likely go away, I won't worry about it. I'm just not as confident in my automotive knowledge as I am in other technical endeavors.

 

A little update. I did use a torque wrench btw. I took it to my uncle, a semi-retired mechanic. The error code said there was a misfire. Turns out I had a defective spark plug. Everything seemed a bit better, maybe it was just wishful thinking because it's still shaking and the check engine light came back on. I don't know what the error code is yet. When I cleaned the intake manifold I didn't clean the mass air flow sensor. I don't know if that has anything to do with it but I'll clean that anyway. There is about 190k miles on it so it's been around. But this is the first issue we've really had with it and I've taken good care of it and made my regular maintenance appointments.

 

It said there was a misfire on one and four. One had the defective spark plug. The porcelain was broken inside or something. The filament in the center was freely sliding up and down. My uncle said sometimes one misfire can cause another and suspected that's what was happening with four. I do have a regularly scheduled maintenance appointment at the dealer tomorrow and hopefully they can give me for information. I don't want to keep bothering my uncle about it and he lives 20 miles away as well. I do have a cheap OBD2 bluetooth scanner but the damn thing never worked.

 

It's been a while and I had this resolved. Just to give an update, I ended up just taking it into Toyota. I'm glad I did because there were a few issues that took the tech a while to sort out. I don't recall exactly but if anyone is curious I can probably find the invoice.