P0301 leading to P3191 (rabbit hole problem chasing)

I am at my wit's end for this issue, and I am hoping you guys can lend me a hand.

This weekend my wife's 2013 Prius threw a P0301, and would knock on startup but would ride smooth after. I checked all the following things to make sure I wasn't missing anything:

• Air Intake Manifold is clean (with new gaskets)
  
• Spark plugs are new (10k miles)
• Ignition Coil Boots are new (10k miles)
• Fuel injectors are clean
• PCV valve is new (10k miles)
• EGR valve is clean
• Coolant levels have not depleted

I added some fuel system cleaner to the gas tank and then swapped the spark plug and ignition coil from cylinder 1 to cylinder 2 to try and catch if the code moved. After doing this the car stopped misbehaving - it may make a slight rattle once in a while but overall wouldn't throw a "check engine" light.

Well, today my wife says the car smells like gasoline inside so I figure when I was putting the fuel injectors back I didn't properly seat the o-ring and it may have a small leak. Tonight I tore back into it and made sure to tidy up the injectors, but the car started throwing a lot of gasoline out while I was working on it (had the gas cap open to relieve pressure). I got it cleaned up and put it back together.

Here is where it gets screwy - when I went to start the car, the engine jostled once and then stopped. Then it tried again to start, but couldn't. Waited until the system threw a warning at me: "Traction Battery Protection Mode; Restart After Shifting to P Position". I got out and ripped everything back out again, made sure everything was where it was supposed to be and all the connections were solid. Got back in to start, same issue - engine would not turn over, and the car went to battery protection mode.

The car was half in my garage so I put it in neutral and let it roll out my driveway so I could at least close the garage. Changing gears was noisy, and once it came to a stop the system finally said "Check Hybrid System". I disconnected the hybrid battery and the 12V, waited and hooked them back up. Tried to start it again and the car got a little further - engine rattled and was noisy as hell, then it quit and hit me again with the "Check Hybrid System". Finally got a code - P3191.

I do not know what else I can do folks. Any advice would be super appreciated.

 

Quick update: I followed this thread which seemed close to my issue - fuel injector dumping fuel all over the engine, car not turning over, etc: P3190 P0A0F after cleaning injectors! Car won't run! Plz Help! | PriusChat

I am following the guidance here, and noticed when I took my spark plugs out to let the car dry there was a bent connection on the first cylinder plug. I picked up new plugs and a borescope to see what I can find inside if there's any damage to the cylinder.

 

Another update: got back home after the car had been sitting for the last 5 hours and put her back together with brand new spark plugs. Got my borescope to check the holes before putting in the plugs, and cylinder 1 was oily-looking. Used compressed air to blow it out as best as I could and it cleaned up slightly more.

Once I fired it up, the engine came to life but rattled like crazy. I put up a video but my account isn't old enough to post it yet.

Now the codes on my reader are P0010, P0351, P0352, and P3191.

 

It's at 242k miles. And you're right - the EGR cooler has not been disassembled and cleaned, only the air intake manifold and the EGR pipe assembly.

I finally threw in the towel and am having it towed to a local mechanic I trust with it; my wife's out of patience while I try and figure this thing out. The codes keep changing and new problems emerge, so I'm all out of time to figure it out.

 

The new plugs I got were NGK plugs. When I saw the bent tip I figured it might be best to just replace the lot of them.

 

I'm the second owner - bought from the original and only owner last year. I haven't seen a drop in coolant since we got it, so I originally ruled out a head gasket issue. Doing the "EGR pipe assembly block" test didn't yield any improvements back when the issue first started, so I also ruled out the EGR at that time. Moving the spark plugs from the trouble cylinder to another and cleaning the fuel injectors seemed to solve the issue, and the cascade of issues started after removing the fuel injectors (again) and re-seating the o-rings correctly to stop the smell of gas from entering the car.

After that it's like the whole thing just decided to crap the bed, so I was surprised I made it that far with few issues only for the entire car to just fall apart mechanically after the gas spill from the fuel injectors.

 

So another update - shop called me, still diagnosing the problem even 24 hours later. However, they did spot the oil in the 1st cylinder (in the pictures above) and after draining the oil found glitter inside from metal. So their hypothesis at this point, before finishing their diagnostics, is possibly a cylinder bearing wearing down or out. Hopefully they let me know tomorrow what the skinny is.

Provided there is an issue with the 1st cylinder, is it going to be worth it to replace the cylinder or am I better off ordering a JDM engine and having it swapped out altogether?

 

I am just trying to think of the best way to get her back on the road - my wife is really attached to this car and money is incredibly tight, so cost-effective but long-term solutions to the problem are going to be the move if we can hack it.

 

I just got the bill for replacing the engine with a used JDM - $3,370 for the whole shebang. The engine cost is $1,750 from one of their suppliers. Seems kind of high from all the comments I've seen on Prius Chat.

 

Do you think there's a risk of the transaxel or generator failing before I get the life of the engine paid for? I don't want to drop big $$$ on a repair only for another major component to crap the bed in the next few years.

 

Sometimes the Mrs wants what she wants. Nothing much I can do about it