Lexus CT200h Forums banner

Blown head gasket.Just for help. Hope i dont get in trouble for this

17422 Views 47 Replies 11 Participants Last post by  Perl1947
I ran into.this thread from a Similar forum for prius. Really hope it helps us you have the same problem.

1 - 20 of 48 Posts
This is a mechanics point of view
although his intentions are willful, and he’s close with thermal expansion, but there is more to the metallurgy..

the Atkinson Cycle engine is already designed with thermal expansion as a Given by us engineers..

it is not a squashing issue..

it is a out of order thermal condition that takes out the gaskets..

If a cylinder is misfiring, for Any period of time, thermal expansion becomes uneven, sanding stretching the head gasket..

this applies to ALL Atkinson Cycle Engines.. Chevy Ford Toyota etc..

Before jumping to “oh it’s EGR then”
this engine management system will Alert the system of Restricted EGR and pop a CEL.. $ave money clean it then..

just make sure to change plugs every 60,000 miles with dirty US fuel and fuel stations.. And throw a bottle of Lucas fuel injector cleaner in gas tank at a fill-up once every couple of months..

Lucas injector cleaner is the only one without the distillates that rot gaskets
See less See more
  • Like
Reactions: 2
Thanks MichaelG65, it's great to hear from someone who really understands the engineering!
Tom
  • Like
Reactions: 1
This is a mechanics point of view
although his intentions are willful, and he’s close with thermal expansion, but there is more to the metallurgy..

the Atkinson Cycle engine is already designed with thermal expansion as a Given by us engineers..

it is not a squashing issue..

it is a out of order thermal condition that takes out the gaskets..

If a cylinder is misfiring, for Any period of time, thermal expansion becomes uneven, sanding stretching the head gasket..

this applies to ALL Atkinson Cycle Engines.. Chevy Ford Toyota etc..

Before jumping to “oh it’s EGR then”
this engine management system will Alert the system of Restricted EGR and pop a CEL.. $ave money clean it then..

just make sure to change plugs every 60,000 miles with dirty US fuel and fuel stations.. And throw a bottle of Lucas fuel injector cleaner in gas tank at a fill-up once every couple of months..

Lucas injector cleaner is the only one without the distillates that rot gaskets

Wondering what your thoughts may be on my situation. I have a 2012 CT with 168k and just recently had the hard shutter issue. It happened 3 times before I decided I wasn't moving the vehicle any further until I diagnosed it. Got the CEL to come on and the code was for a Cylinder 1 misfire. Had the oil changed and all fluids topped off, and the first start after was smooth but it wasn't long into the trip before behavior he explains in the video started happening.

I'm assuming it's best to go ahead and do the head gasket, but thought it may be worth it to go ahead and have the EGR system cleaned while it was apart. Are you suggesting otherwise and to just stick with the head gasket for now. I know advice like this without seeing the car in person is to be taken with a grain of salt, but curious about your opinion.

Thanks
See less See more
Received your email alert
I have email alerts enabled, so i may respond faster to requests..

I just posted a follow up to someone on another chain. Rather than retype as I did yesterday with a different response, I’ll paste the original quote.. “what is it”

On to your message;
the Duration of your banging is important, and you noted 3 times.. Did you notice (prior to topping off fluids) level of engine coolant, was it low, discolored from clean stock? Easy to verify this, compare to hybrid coolant tank, same stuff separate system..

IF all was fine on the coolant side, swap plugs and coils and go for a ride before just digging in on the head gasket..

If it’s too late and head gasket time, and you feel confident after reading the below Quote, I definitely recommend flushing out EGR- pipes, can, flow tube, valve, and anything else you feel like cleaning like the throttle body, since all is removed and accessible.. Inspect pieces as you go, common sense looking, for pressure cracks n such..

All engines with some mileage on them enjoy a good EGR flow cleaning 👍

Simple simple simple..
Starts Banging SHUT IT DOWN..
Don’t let these Atkinson engines bang..
They don’t like it, and it will cause damage rather quickly, like Less than 30minutes quickly..

Change the plugs, Ensure gaps are .041
Still a bang, coil going out, Replace them
Have a nice day..

Don’t fret this EGR money dump scam, system is designed to warn driver of EGR Restrictions, clean it then..

Mind you, this is IF you catch it fast enough.. Like don’t drive home or to the dealership Banging away..

Let it bang, well your in for a few surprises-
1- intake manifold gasket goes out
2- head gasket goes out
3- wrist pin circlip pops
4- throw a rod out the side of the block

so what is this Bang “?”
It is an out of order firing of gases in the cylinder head behind the valves when a spark plug is not firing.. Want to test this yourself, pop the hood unplug a spark plug coil, or pull the coil over plug off the spark plug, go start it for a second.. Bang Bang.. This procedure is called Duplicating The Complaint, at dealerships that say they Can’t Duplicate the customers complaint..

Atkinson engines have a valve timing for fuel efficiency, some gases blow back for reburn.. Spark plug not firing, the next cylinder fires the unburnt gases, explosions in the cylinder head.. that’s enough to take out the intake gasket if left banging till it clears up.. While this is happening we have an out of thermal balance of heat at cylinder Deck, allowing uneven thermal expansion of the cylinder head, takes the head gasket out.. Like sandpaper.. Let us not forget, as SOON as it starts banging we have undue stresses on the wrist-pin, that if left Banging, takes the circlip out that hold the wrist-pin in place.. well now that holds the piston and connecting rod together.. Boom throw a rod out the side of the block, it’s done..

this all cumulates to Having a Bad day..

and yes the Manual is Wrong..
Change plugs every 60,000 miles, not 120,000 miles as per Properly Dealership Maintained

that’s it.. Enjoy your CT’s and Prius’s and Ford Fusions and anything else using the Atkinson engine
See less See more
  • Like
Reactions: 1
Okay I'll give you a brief run-through of what I know as of now and what has been done. Initially, I was approaching an oil change and leaving town. Let a family member drive the vehicle and asked them to add check oil level and add a quart if it seemed that it needed it. They added an STP branded oil additive that was quite thick rather than adding.

First start immediately following was rough for the first 10-15 seconds and then it smoothed out. It showed the same behavior twice more and threw the CEL at which point I took it straight in to have the oil changed.

After reading through a few threads I decided to check the coolant level, and it was low, but I couldn't tell you if it were a significant drop in level or just because it hadn't be topped off since the last oil change (roughly 7500 miles).

After having the oil changed and topping off the coolant it ran smoothly for 2-3 days. Yesterday morning start-up was smooth, and then it began to behave as described in the video in this thread. When coming to a stop, and the motor having time to shut off and then re-engage, it was the rough shudder for 10 seconds and then smoothe. It did so 3 times in the 5 miles between where I turned around and made it back home.

I then decided to pull the plugs and have a look, and while I could tell that it had been awhile since they were changed only the plug in cylinder 1 showed significant signs of wear or as if it had fouled. I have only started the vehicle in EV mode since to move it to a spot where it can be easily towed if necessary, but haven't gone that far quite yet because I saw the post you tagged and it gave me enough motivation to not move it.
See less See more
  • Like
Reactions: 2
Please tap “Click to Expand” on my previous post to read the details.. This will allow you to better judge the next course of action, and what steps to take in your specific situation..
👍

I myself would take the simplest route 1st

IF all was fine on the coolant side, swap plugs and coils and go for a ride before just digging in on the head gasket..
  • Like
Reactions: 2
Thanks for the timely responses. That's what I'm thinking the next best step may be is to keep it simple while possible. Going with a leak detection test and coils, and hopefully, that'll end with good news. May as well go ahead and clean the EGR system at this point, but that doesn't seem too tedious just time consuming.

Thanks again for the quick responses
  • Like
Reactions: 1
One last question...is it worth going as far as having the intake manifold cleaned if going ahead with the EGR system?
  • Like
Reactions: 1
Sorry the delay, email dumped last alert into spam, going to fix that one day, whitelist ct200hforums.com everyone..

anyway- I’d probably wait out cleaning the intake manifold at this point, but at least get an eye on the throttle butterfly, that’ll give you the heads up on the manifold.. flashlight and a telescopic mirror to see backside, butterfly to throat bore seating etc..

But.. if you’re digging in, of course absolutely, it’ll be in your hands anyway..
  • Like
Reactions: 1
I had to take a few days hiatus for my sanity. I was diving too deep into it without any tests having been completed.

Update: I pulled the plugs and changed the coil in cylinder 1 before having it towed to a shop nearby to have a leak detection test and evaluation of the motor/compression. According to the technician all tests looked good and it showed no signs of leaking. Their best guess was "We don't really know." which basically leaves me back at square one.

Immediately upon start it gave the hard shudder once more and I drove 10 miles to the house with smooth riding. Popped the hood and it was noticeably hot. Not overheating, but definitely hot, and the coolant reservoir was drained.

All signs point to head gasket, but the leak test didn't show any leaks. I'm diving into the EGR system today but unsure if it's worth the effort or I simply find a shop willing to replace the head gasket without it "showing" any signs of leakage.
See less See more
I had to take a few days hiatus for my sanity. I was diving too deep into it without any tests having been completed.

Update: I pulled the plugs and changed the coil in cylinder 1 before having it towed to a shop nearby to have a leak detection test and evaluation of the motor/compression. According to the technician all tests looked good and it showed no signs of leaking. Their best guess was "We don't really know." which basically leaves me back at square one.

Immediately upon start it gave the hard shudder once more and I drove 10 miles to the house with smooth riding. Popped the hood and it was noticeably hot. Not overheating, but definitely hot, and the coolant reservoir was drained.

All signs point to head gasket, but the leak test didn't show any leaks. I'm diving into the EGR system today but unsure if it's worth the effort or I simply find a shop willing to replace the head gasket without it "showing" any signs of leakage.
Does it have egr fault codes?
Pretty weird the mechanic didn't find any leaks but your car lost coolant.
Perhaps check under the throttle body for signs of oil bypassing from pcv. Also, If your oil level is topped off, remove until half way between the marks. My car hasn't shuddered since this and trying to find out if its just coincidental. Also, why did thou ask your relative to add oil? Was it consuming oil? If the mechanic said compression was OK, that would mean the oil leaking or that it was getting sucked into the intake via pcv.
  • Like
Reactions: 1
Does it have egr fault codes?
Pretty weird the mechanic didn't find any leaks but your car lost coolant.
Perhaps check under the throttle body for signs of oil bypassing from pcv. Also, If your oil level is topped off, remove until half way between the marks. My car hasn't shuddered since this and trying to find out if its just coincidental. Also, why did thou ask your relative to add oil? Was it consuming oil? If the mechanic said compression was OK, that would mean the oil leaking or that it was getting sucked into the intake via pcv.
The only code I've gotten so far is the cylinder 1 misfire. I pulled the EGR pipe today and it was a disaster so I know that I need to go ahead and go through with the entire EGR cleaning process. At this point, it's looking like it might be worth the effort to do the intake manifold as well. With that removed, I may as well go ahead and do the PCV also it seems.

The oil level was low when approaching the last 2 oil changes which was why I suggested adding a quart
My only guess as to why it may have burned through the coolant is the clog in the EGR system. I have nothing otherwise as mentioned above, all compression and leak tests came back with good results
My only guess as to why it may have burned through the coolant is the clog in the EGR system. I have nothing otherwise as mentioned above, all compression and leak tests came back with good results
If you find a puddle of oil in the intake below the throttle body then you know where the missing oil is going and probably fouling the plugs.

Your oil was how low before prior oil changes? Below the lower line? What type of oil do you use? How often do you change oil?
  • Like
Reactions: 1
Maybe scope the cylinder number 1 after a drive.
Okay...I've finished taking everything apart. Have removed and cleaned intake manifold and every aspect of the EGR. Also replaced the PCV valve while I had it apart. Letting everything dry out currently.

My only question at this point is how well is fluid supposed to flow through the EGR assembly? That may be a naive question, but I'm curious as I clean it out
About as well as it would flow through the fins a 8in thick radiator.
Does it have egr fault codes?
Pretty weird the mechanic didn't find any leaks but your car lost coolant.
Perhaps check under the throttle body for signs of oil bypassing from pcv. Also, If your oil level is topped off, remove until half way between the marks. My car hasn't shuddered since this and trying to find out if its just coincidental. Also, why did thou ask your relative to add oil? Was it consuming oil? If the mechanic said compression was OK, that would mean the oil leaking or that it was getting sucked into the intake via pcv.

Here is where I've ended up. I know that the oil level was low when getting close to time for an oil change for the last 2 oil changes, and I mean considerably low (below the lower line). The coolant I honestly couldn't tell you because I hadn't monitored it because I hadn't experienced any overheating issues. The level was supposed to be checked and/or topped off at oil changes, but there was no mention of it by the service techs.

I haven't checked the oil level since doing the work that I've done so far, which is such: pulled intake manifold, throttle body, and egr system and thoroughly cleaned them. There was some oil pooling in the bottom of the intake manifold when I pulled it, and I went ahead and did the PCV valve after having pulled everything else. I've since changed the plugs and ignition coils.

Initial cause of concern was the hard shudder and CEL for cylinder 1. I changed oil and plugs after this and had it reset before having another hard start and moving on to egr work. After doing egr/intake manifold/throttle body work it ran smoothly for first few starts and then had hard shudder once more and CEL came back. CEL was now for a misfire in both cylinder 1 and cylinder 2.

Bought the ignition coils and swapped them and am still experiencing hard shudder with CEL being thrown. Haven't had the codes scanned yet.

I also haven't checked the oil level, which I would assume is still near the top line on the dip stick. The coolant level has remained, but it hasn't been driven more than 10 miles as that sound from the hard shudder sends chills and makes me worry for further damage.

I am curious to know if that drop in oil level has been that significant for you. That seems bizarrely simple.
See less See more
1 - 20 of 48 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top