My mom has a 2012 Lexus CT200h and a few times over the last year when starting it sounded like it was coming apart as she describes it. Her normal mechanic felt better if she took it to the dealer as her's is the only one he has worked on. Dealer came back and said they bore scoped it, saw coolant in #3, quoted replacing engine, intake, and EGR to a total of $12,500. She freaked a little. Her mechanic said bring it back to him. He did a coolant pressure leak down with no leak down over 12 hours. He recommended an independent shop that specializes in Prius and Lexus hybrids to look at it. Mom went in there described the issue and guy said he didn't want to work on it because there was no real fix. He said the engine would eventually fail.
So research shows lots of TSBs indicating EGR and intake issues. Seems the intake has been redesigned maybe to help this issue. Other things on the internet says head gasket failure causing hydro lock on start up is the issue. Possibly two different failures giving simular symptoms?
I think that is the same motor as a gen3 prius, which has an issue with head gaskets. And I am not sure if a pressure test on a head gasket is indicative of condition. The combustion pressures are much higher than a tester can handle.
A buddy of mine has a couple of Gen 3 Prii and has repeatedly had to take the EGR system apart and clean it. When it clogs up the car will misfire and rattle and sounds like the bottom end is coming apart.
Clean EGR system and it's back to normal. Dunno what exactly makes it sound so bad, but EGR was the issue.
I have no Gen3 experience but egr is a super common problem. HG is a problem too but I'll bet they are defaulting to HG as a reason to not work on them.
I recommend egr research.
I've watched videos this morning and the intake and egr aren't hard to replace. Think we'll do that over Christmas.
John Welsh said:
I have no Gen3 experience but egr is a super common problem. HG is a problem too but I'll bet they are defaulting to HG as a reason to not work on them.
I recommend egr research.
+1
As awesome as the gen 2 prius is for reliability, the gen 3 is equally infamous for clogging EGR's and popping head gaskets. That's why, despite owning 9 Priuii, I have yet to buy a third gen.
Mine also did that and cleaning the EGR passages and cooler fixed it. If left undiagnosed it often leads to a blown headgasket, hence the car's reputation.
Can confirm. I own also own a 2012 CT. It is a clogged EGR system and intake manifold that causes the death-rattle sound. My car did the same and I replaced the headgasket around 180K. The EGR cooler was completely clogged. Even the nastiest of chemicals I had wouldn't go through the cooler, so I ended up buying a replacement. The intake manifold is super easy to clean, though. I also added a catchcan to the system as these cars are oil burners and it catches quite a bit of gunk. It is still running great at 235K miles now.
Since replacing the headgasket, I've just made cleaning the EGR/intake an annual thing as preventative maintenance. It only takes me a couple hours to do the job. There is one bolt on the cooler that is blind and kind of a pain, but the rest is easy to access.
I'm getting the parts list together. Is there a gasket between the intake and the EGR pipe? I found one between the pipe and EGR valve.
In reply to Stampie :
Yes, but that one is a reusable rubber one. Same for the intake manifold and throttle body gaskets.
Oh, and you'll also need an E8 reverse torx bit to remove 3 studs to make removing the cooler possible. Remove the 2 studs on the back of the cooler where the exhaust bolts up to it, and the one stud in front of the EGR valve itself. Leave the stud of the hidden nut on the bottom of the cooler. Everything else is 10 and 12mm.
In reply to Spoolpigeon :
Cool. Thanks.
I keep wanting to investigate it, but does anyone know if the earlier engine can be swapped into the Gen 3 relatively easy?
In reply to Indy - Guy :
Maybe there is a business case for buying gen 3 Prius with death rattle, cheap.
Change egr.
Sell without death rattle for profit! ???
John Welsh said:
In reply to Indy - Guy :
Maybe there is a business case for buying gen 3 Prius with death rattle, cheap.
Change egr.
Sell without death rattle for profit! ???
It's like you're reading my mind....
In reply to Spoolpigeon :
Have you tried an oil catch can? I mentioned yearly cleaning and that wasn't something she's interested in. Seems most of the gunking up is how much oil gets put into the intake.
EDIT - reread your post and yes you have. I'm a DA.
In reply to Indy - Guy :
I await the first entry in your new thread.
hobiercr said:
In reply to Indy - Guy :
I await the first entry in your new thread.
Do you guys really want to read about a Prius based repair business?
In reply to Stampie :
No worries! The catch can really does catch a ton of gunk, especially on high loads. When I travel to Kentucky from Virginia Beach, there are some long, steep hills to climb and it seems to catch the most then. It's also kind of weird that the PCV valve location is so low on the block. That might be a contributing factor also.
I got a cheap CC on Amazon and made a little bracket to bolt it to the valve cover. It almost looks OEM-ish. 
Indy - Guy said:
I keep wanting to investigate it, but does anyone know if the earlier engine can be swapped into the Gen 3 relatively easy?
the main trick, afaik, is to swap a Gen4 engine into the Gen3's... although there's some accessories that need to be changed over, iirc. pretty sure there's a couple of outfits that specialize in this already (brought up in the Prius V rebuild thread, I think).
Good timing Stampie! I'm doing the same repair over the christmas break on my 2012 Prius V w/121k
From what I've read Head Gasket is a pretty common repair on these before they hit 200k, but you're still buying time by cleaning the EGR. If the EGR is blocked it creates too much heat on one of the cylinders and the HG blows.
Where is the Prius V rebuild thread?
EDIT- Found it: https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/2014-toyota-prius-v-lets-try-this-again/259684/page1/
Bump.
What YouTube tutorial do you guys recommend for showing how to do this cleaning?
cause I drug this home :
No power, death rattle and here's the codes
In reply to Indy - Guy :
The codes I generally see associated with the death rattle are misfires. Maybe you have two issues? For my mom she bought all new parts for around $1k. Yesterday Lil Stampie and I hit the junkyard and grabbed this for $36. I have an ultra sonic clearer on the way to experiment.
We also used the junkyard engine to gain experience in removing it. The problem is the cooler and the EGR have studs in planes 90 degrees apart. What I found worked was removing the studs that went transverse into the block and leaving the longitude studs at the back of the EGR cooler. We removed the EGR and the cooler as a unit that way.
