1nz-fxe Prius engine long block swap options

Hello my 2006 prius has 264,000 miles on it. I got it at 240,000 miles on it burning 1quart of oil per 400 miles. (It had gone 40,000 miles with out an oil change just top offs)
and a check engine light on for misfire on cylinder 3. The spark plug for cyl 3 was oil fouled and I replaced all of the with Iridium plugs and replaced the PCV valve after that dropped the burn rate to 1quart of oil burnt off per 1,000 miles and the check engine light did not come back until 20,000 miles later with scheduled synthetic oil changes.
As an experiment after noticing the cylinder #3 oil fouled again I sprayed into the cylinder “CRC GDI IVD Intake valve and turbo cleaner” which claimed to have the highest % PEA detergency. I jacked up the rear of the prius because the engine is tilted back and I wanted it to be level so the fluid would cover the rings evenly, I sprayed into the cylinder every hour for 5 hours and let it sit overnight. I thought I would be a good Idea to turn the crank back and forth but didn’t do it. Next morning I vacuumed any exes fluid in the cylinder and installed a new iridium spark plug and did an oil change, filling the oil filter with Seafoam additive.
Results; I commuted 200 miles round trip once a week keeping an eye on the oil before and after the trip. The oil burn was minimal to the eye totaling under a quart per oil change at 3000 miles. But the check engine light for cylinder 3 misfire was still showing up after a 2 mile trip to the gas station and parking the car for about an hour before driving 100 miles to complete the round trip. It always happened like this. I stoped reseting the check engine light so it was lit and after doing a Italian tune-up the check engine light turned off and stayed off for months with minimal oil consumption.
Now it’s burning about 2 quarts per 3,000 miles and the check engine light keeps coming back about a week after I reset it.

I saved up to get a JDM import low mileage engine (I’ve done this with many of my past vehicles like a 97 camry that went to 400,000 mi after the original engine was replaced with a JDM at 200,000 miles and it was totaled in a rear end colition) but all the JDM importers here in Southern California are out of stock on the 2nd gen prius 1NZ-FXE they have plenty of the Prius C 1NZ-FXE from ‘12-‘19.
I know this question has been asked before (I read that whole thread). I am taking about using the long block from the C and bolting all the stuff from the 2nd gen. That is the big question will all the stuff bolt on? The bracket that holds the mechanical water pump in the 2nd gen will it bolt up where the bracket that holds the electric pump. Intake manifold and exhaust? Transaxle bolt pattern? I know someone said they bolted up a Yaris engine to a 2nd gen prius and ran fine so it’s likely.
Why finding out if the 1NZ-FXE from the C would work in the 2nd gen is important to us 2nd gen owners? Possibly piston oiling improvements reducing future oil burn. The timing chain is improved. More lower mileage engines available.

I don’t know if I’ll find out these answers first hand. I will try the intake valve cleaner on that cylinder one more time and replace the spark plugs with double platinum this time and hopefully get good results for a few months until JDM engines are back in stock. If a prius C lands at one of the many pick your parts in the L.A. area I’ll get the block and start doing some hands on comparisons between the two engines.

 

Thanks DOLJ best response so far

I did soak all pistons at the time but left that out because the post was getting really long.
Also I was mistaken on my oil change intervals not 3,000 but 5,000 miles so months after this first experiment It’s burning about 2 quarts every 5,000 miles, I’d be ok with that if not for the check engine light for cyl 3 accompanied by oil deposits on the plug.

I agree, I decided long ago never to have an engine or transmission rebuilt. I’ve known people who have spent thousands on rebuilds only to have them break in to pieces a year later with warranties not worth the paper they are printed on.
I have bought low mileage JDM engines and transmissions localy in Los Angeles, because of harbor back ups they are out of stock. I not just looking for any used engine. I’m only buying JDM from my trusted source They may be back in stock soon.

If they are back in stock at my trusted seller I will buy the correct engine for the 2nd gen. But I will still find out if the long blocks between the 2nd gen and C are interchangeable. Sure there will be different pin outs for sensors but If every thing fits in the same holes. Like all the other times I’ve changed and engine and bolted all the different things from one to the other.

For now I’ll do another piston soak, oil change and this time I’ll put in the double platinum spark plugs as I suspect the double platinum arc points will burn off oil residue better and not misfire.

The reason I bought this neglected prius was to get some hands-on experience on the marvel of engineering that is the Gen 2 prius and what a great decision that was this has been a great car.

 

Apparently initially I did post it in the wrong section, I could have sworn I put it in the 2nd gen main forum.
Anyway, I would love to get a rolled-over prime and swap everything into an 2nd gen MR-2. Or even better into the shell of BMW i8. But that’s a fantasy build.

It would be interesting to see some full build videos of prime swaps into cool 90’s Japanese cars.