Prius G3 Misfires/Head Gasket issues same as in Lexus Ct200h?

Hi All, first post here. Reading a lot about the engine misfires on startup (with P030x codes) and the issues with EGR, intake, and head gaskets on the G3 Prius. In my case, I just started having the same symptoms on my 2011 Lexus CT200h. I believe it is the same engine (2ZR-FXE) and drive train. A search of Lexus forums has a little info on it but not nearly the same number as here. Any input on next steps or final resolution to this issue would be appreciated.

To answer some common questions:
Car: 2011 Lexus CT200h
Mileage: 159k
Symptoms: Shake/shudder on startup, seems worse when car is restarted when still warm (30-45 minutes after shutting off). CEL on: Codes thrown: P0300, P0301, P0302, P0303, P0304. Started about a week ago, not all codes get thrown every time car is started.

Oil Usage: None, Have never added oil between 10k changes with full synthetic. Oil appears completely normal (no milky appearance) and no crud on underside of filler cap.

Coolant Usage: Slight drop noticed after problem started. Topped off and no noticeable drop yet, though I have minimized starting/driving car. My OBD2 scanner shows coolant temp of 180-190 after 30 minute drive; I don't believe it has ever overheated. Coolant was changed at 120k with Toyota Long Life; old coolant looked exactly the same as new coolant.

Smoke from tailpipe: Very slight, only immediately after starting for 5-10 seconds. You would need to be standing there looking for it to even notice.

EGR: Lexus had a service campaign on this issue way back in 2012 or so and I did take car in and have that done, as I recall they replaced "EGR control unit." Haven't touched it since (my bad evidently).

Done so far: After very first CEL/Code of P0302, I swapped coil and plugs between Cyl 2 & 3 to see if code followed coil. It didn't. Next code read showed P0302, P0300, P0304. Took to independent shop who diagnosed bad plugs (I changed out originals at 110k with OEM Densos), They were confident new plugs would resolve: it didn't.

Questions: Am I looking at first signs of HG failure? Could it be EGR cooler leak instead of head gasket? Is the complete EGR cleaning doable by shade tree mechanic? (I have done all the oil/filter/coolant/plugs/brakes on this car since new). If it is HG, is replacing it better than swapping engines, giving my no oil usage on this engine? This has been too good a car and in in such good shape otherwise, I feel it is worth fixing but I don't want to assume the worst and I don't want to be at the mercy of diagnosis of shops not very familiar with this specific problem, they just guess and start replacing parts that do not fix. Thanks for any suggestions!

 

Thanks Ray. Thanks for quick response! I took it to Ozmotive in Sacramento. They specialize in Hondas and Acura but they work on all Japanese cars and have done a good job for me in the past. But I just don't think they're familiar with this particular problem, so I hesitate to return there. I have not pulled the EGR pipe and it is something I might attempt to do myself as well as the full EGR cleaning process. I'd like to make sure that is in good shape before I proceed with any other major repairs. Does that make sense?

 

Thanks. At this point I'll take all the help I can get! With 6 EGR jobs under your belt, you sound like an expert to me!

I see you're in Fairfield. Not that far from me (I'm about an hour east of Sac). If you have time and want to supervise the job so I don't screw it up, I'd be happy to bring the beer, or your drink of choice! Or we could do it here. -Dan

 

Thanks @Raytheeagle, @xerox6135, and @Mendel Leisk. I'll try to look at the EGR pipe myself this week to see what it looks like.

I'd love to come to the meetup on the 18th if y'all don't mind a Lexus CT200h invading your Prius group! I've spent the morning watching @NutsAboutBolts videos (great work! thanks) on EGR cleaning and intake manifold cleaning. Never done any of this stuff before and some experienced eyes and guidance would be very helpful and appreciated!

The car has ran so well for so long (has NEVER been to a shop for any repair of any kind, other than Lexus recall/service bulletins!) that I haven't been proactive enough to be aware that this EGR issue might be a silent death slowly creeping up on me. I've done all scheduled maintenance myself and thought the car would last many more trouble-free years. And then boom, one day the shaking on startup and MIL/CLE light with P030x (misfiring) codes.

 

Removed the EGR pipe today to take a look. It was definitely gunked up but air still flowed freely through it. Some before/after cleaning pics are attached (if I can figure out how to attach or have rights). Does this look normal for 159k?

 

I will come on Sunday for the EGR circuit cleaning. Thanks again for the invite. Where in Fairfield is the meet? Time? What should I bring in the way of tools, cleaner, etc.? Don't know that I have all the specialty tools for removing studs.

And just throwing it out there, what is the concensus on driving the car there if this is a head gasket issue I am facing? Do I risk damaging the engine further? It's about a 90 minute drive to Fairfield. I am not sure if I am losing coolant since haven't driven it much at all since this started. But after first codes, the coolant level was lower than it has ever been, so suspect I am.

Also, I did notice that, compared to @NutzAboutBoltz videos, that my 2011 Lexus CT engine bay is not identical to his Prius. All the components seem the same but the layout is slightly different. For example, I do not have to remove wiper motors and cowling to change my spark plugs, the MAF sensor plugs in at different spot on air cleaner housing, etc. Not sure about the rest of EGR system.

 

I will bring beer!
You guys have a favorite flavor?

Does the EGR cleanse require any new gaskets?