Swapping in a Gen 4 Prius' 2ZR Engine into the Prius v

Too late I guess. I already paid for the Gen 4 engine from a local JDM place. Should be delivered later tonight. The engine looks to be in good condition, no leaks that I could see, low miles, no cross threaded drain plug. Plus it's coming in at a little over $1800 with delivery included. To get a similar build from Hybrid Pit would be over $2600 plus whatever the delivery fee is and however long the lead time is. I'm hoping to have mine up and running by this weekend because it's really tough being a 1-car house.

I did think about replacing the head gasket but reviewing the videos and such, this should be faster and "easier". I'm willing to take a chance. If I still have issues, I can always attempt to change the HG on the old engine.

 

You do have to use a lot of your gen3 engine on the gen4 to make it fit including the egr system. Plus some wiring and cooling system changes.

 

Just going to throw in there the Gen 4 block Gen 3 head swap I did never overheated. Possibly due to NOT having to reroute coolant lines required to use the Gen 3 EGR cooler with the Gen 4 head? I’m just guessing here. But I did have to flush the “mechanic in a bottle” out of my system with vinegar/distilled water and clean a glob of junk out of the thermostat in the Exhaust Heat Recovery Tank.

 

with the Nexpower V2.5 car still gets 610-625 miles per tank on flat ground driving easy.

 

Hey Durham neighbor!
Your situation kinda looked similar to mine years ago. I picked up a 2010 with about 140k miles back in late 2018. I had a 200 mile daily commute to to my job on base and needed something other than my thirsty V8 that takes Premium

Features wise, I still miss the solar sunroof and leather and interior room (along with not being noticed when I hover around 90mph), but dealing with why I wasn't seeing the MPGs this was supposed to have, coupled by the oil consumption, EGR and then eventual HG issues, I decided to do the Gen4 swap in mines- mainly because an Engine Swap looked much easier than HG repair on my own.

@Ragingfit videos along with the posts here in this helpful forum are what I primarily used.
In the end I couldn't nail down the overheating issues after the build and I had my buddy who used to be a Toyota Master Tech who now runs his own shop take a look at it. I enjoyed the idea of surprising him on what I did with this Gen4>Gen3 chassis. After he spent some time checking the install over and bleeding it a few times, he figured in the end the engine I got from an ebay seller junkyard in Cali was just bad- it was pulled from a roll over...which may be why it cost me $1000 shipped from CA<>NC.

I still hang out here keeping up-to-date on the TurdGen and 4th Gen issues and casually look for CT200h's with busted engines to snag and am willing to do this swap again, as overall although this swap looks like a massive undertaking, it's not that bad of a garage project to take on. This was my first engine swap and largest project I've ever completed and afterwards I can say that I did have a lot of fun and learned alot and have bragging rights on my growing mechanic hobbyist skills.

Will your engine come with some of the attached accessories? I was able to sell the injectors, wiring harness and egr on ebay to make some money back spent on the engine.

Keep is updated on your progress and we'll try to advise as much as we can

 

When I tackle this again in the future, I will be sure to sit down and analyze your posts to see how you've done yours..From what I remember, I stuck w the Gen3 cooling only because the Coolant Re-Routing diagrams shared here and on YT were confusing to me at the time and I just wanted to get this swap done w the least amount of hassle

 

If considering an engine swap, maybe just spring for a brand new 3rd Gen short block, have a machine shop go over the (existing) head.

that’s essentially what @cnc97 did, albeit using a salvage 4th Gen, using everything from the head gasket down.

 

In preparation to purchase a gen4, I noticed some of the gen4 engines appear to have a 'coolant' pipe? that goes from near the engine coolant pump around the back to the egr cooler from what I can tell. I have not been able to find info. Maybe searching with wrong words.

Is this required for all gen4 or is it just on some, but not others. Trying to figure whether I'll need to buy one if this is missing.


picture of what I'm seeing


Also can anyone shed light on 2 other differences I've noticed:
1 some appear to have the removable filter cap to hold the filter media and some have a metal filter all in one.
2 the black plastic valve cover(i think that is what it's called) has a toyota emblem on some and not on others

 

JDM versus non-JDM...also Corolla had different options there.

 

Is that a definite thing? The engines I saw with the emblem and without were both listed as JDM.

Does anyone have any idea whether it matters if that external hose is there or not? After looking at the egr cooler design, that backside hose joins a coolant hose connected to the egr cooler. You can sorta see it in the attached picture.


I found gen4 swap video by HybridApp yt channel, the gen4 engine they used on his does not have the coolant(?) hose running around the back side of the engine.
Also from what I saw in swap vid#7 by FixThatPrius, that engine does not have that hose either.
When checking pics of engines on cartparts website, it appears the 2017 yr engines pretty much all have this hose while the newer ones '21, '20 do not all have this hose in the pics. Guessing it might be associated with internal engine coolant flow design. If so, maybe better?

Thanks for any feedback

 

Finally made some progress on my swap. The first week was all research and figuring out what goes where and why. I took to labeling the hoses, sensors and other parts of the two engines so I could keep track of everything, Why is it so hard to find out what the various pipes are in the S&R manual? It's like Toyota intentionally made all the names difficult to find on purpose! It was like a where's waldo of the pipes and brackets! Ugh! But at least I got the old engine pulled today... after missing that one bolt on the back side of case... Surprisingly, the only f-bombs dropped was when a hose clamp nailed the tip of my thumb when it popped free from the needle nose plyers as I was using. That left a mark!

Since this is really my first time ever tearing into anything more than a simple brake job, here are a few things that have helped as I went along:

• Labeling hoses (part name, coming from & going to),
• Labeling sensors (both on the harness and on the engine)
• Taking pictures (many, many, pictures):
  • of the engine bay, then
  • of my finger pointing to the part/bolt to be removed, then
  • of the removed part/bolts in hand or on the ground near the where they came from

 

Mine doesn't have the hose around back but does have the Toyota emblem. I bought it from a JDM place in Garner, NC. Not sure what year mine is.

 

Howdy back @Ultimate_Combination Durham dude!

I might hit you up for a reference if I get stuck with something similar. Good to know that there's other people that can help close by!

Already posted the pic of the engine getting pulled from the car on the local MTB thread that I'm on that seems to talk about cars more than bikes. I can already feel the "respect karma" increasing by at least 20 points...

Great idea! I was already wondering what to do with the old engine and spare parts. I might only have about a month or so for unloading the parts after project completion depending on the wife's annoyance factor for not being able to use the garage.

 

See this post.

 

For those that have already completed the swap, what was your solution for attaching the Gen3 harness to the engine where the Gen4 water outlet is? The mounting hole is moved about 1 inch forward and the old metal bracket that the harness clips to no longer fits. I'd like to keep the harness supported in that area so that nothing ends up wearing from vibration. I've thought about making another bracket, p-clips, zip ties, or 3-d printed parts, or even drilling a hole in the harness plastic, but nothing seems easy/ideal.

 

Wow I see it's been back in early 2021 that I completed this- I vaguely remember this part and had to go looking through some saved pics I took of this:

If memory serves, this may be one of the many brackets that you will end up not using.
I just cut the lines to the sensor and then added a few inches extra wire, soldered them up and wrapped electrical tape around them so I could get the sensor to connect to the socket from the harness.

 

I'm not talking about the temp sensor- I ordered one of those $15 extension pig tales that someone listed earlier in this thread for that. I'm talking about the thick harness within the black plastic that also has the orange HV cable attached to it. It's a pretty heavy mess of cables & wires under the water outlet (the one with the temp sensor on it, removed from this pic).

 

This is what I am thinking of doing. Use a rubber foam like armaflex(scrap piece) between it and whatever part of the engine I can zip tie it to, so it doesn't pull on any of the individual connectors.

 

OK, got the car put back together and running in maintenance mode. Got my first fault code: P0012: "A" Camshaft Position - Timing Over Retarded, Bank 1. ...and I just double checked the cam position sensor by the vapor pipe and noticed that the harness connector was sitting on the sensor, but not all the way plugged in. Opps! That might do something... lol. We'll see if that fixes things... Keeping my fingers crossed that that is the extent of the issues! Now to deal with the pesky PCS error... yay.

 

Nice- the radiators have been cycling on and off around 95C and 92C. All the bubbles seemed to have been come out of the system. I think it really helped to have the older Gen3 bleed port on the system. Funny thing with the PCS warning, it disappeared as soon as I took it out of maintenance mode. Will take it for a test drive in the morning to see how things go!