Cracked Cylinder Head

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2018 Mazda CX-9 GT
have a 2018 GT AWD with about 38.3K miles, noticed air from heater wasn't blowing as hot & slowly over the past couple weeks that air wasn't getting hot at all. Last Sat while out, had msg on dash/Hud show to pull over immediately. Took to dealer & was told that I have a cracked cylinder head in the rear by the turbo (dealer sends video with a walkthrough done by the tech/mechanic). Thankful it's covered under powertrain warranty, but being told part is on back order & may not be fixed until April/May.

Anyone else have this happen to them? not sure if this was an issue with around with late model 2017 or 2018 or was it just a fluke & it was a bad casting when the cylinder head was made or did someone overtighten a bolt during assembly which caused a small crack that just got worse over time.
 
thanks, i wrote this & then found one of the threads after searching. I'm waiting for the dealer to call me back for clarification on what they are replacing, as when i spoke with them yesterday, they made it sound like they were just replacing the cylinder head.
 
Yes seems like replacing the cylinder head is the new procedure from the TSB, before the TSB was issued mazda was just replacing engines. Some people are still getting full engine replacement though, i guess it depends what the tech finds when they start the repair assessment.
 
found out today that the oil was clean, no coolant, so they are only replacing the cylinder head (also was able to get a copy of the TSB off another thread). Now hopefully I will be getting a loaner car in another day or so to ride out the storm
 
picked up a Rental that dealer is paying for & while at dealer was told they are now doing an engine swap instead of just a header repair (even though they said the oil was clean & had no coolant mixed in)
 
picked up a Rental that dealer is paying for & while at dealer was told they are now doing an engine swap instead of just a header repair (even though they said the oil was clean & had no coolant mixed in)

What kind of timeline did they give you for repair/replacement? Are they covering your rental costs until the engine has been replaced?
 
What kind of timeline did they give you for repair/replacement? Are they covering your rental costs until the engine has been replaced?
I was given the same timeline for both part & for engine. When they originally said they were going to just replace the cylinder head, the dealer told me it would be completed by May because parts were on back order. When i was at the dealer this past Wed night, they said I was going to get a new engine & it was still the same time frame.

My dealer is going to give me a loaner once they have one available (from what i saw on the erase board they had behind the counter, they have about 20 loaners but were all out). For now they are paying for the rental from enterprise but said they were going to get into a loaner by next week because they don't want to pay the rental for long. Though it took about a week for them to get me the rental (first week i had to carpool with the wife).
 
⋯ Anyone else have this happen to them? not sure if this was an issue with around with late model 2017 or 2018 or was it just a fluke & it was a bad casting when the cylinder head was made or did someone overtighten a bolt during assembly which caused a small crack that just got worse over time.
The cracked cylinder head problem from both 2.5L NA with cylinder deactivation and 2.5T with turbo IMO is caused by the modification from the original cylinder head from the 2.5L without CD. The modification for CD and turbo somehow weakened the head in certain areas which caused the crack.
 
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Philly, just a minor correction--Mazda North America is paying all the costs for your rental, loaner, and repair work. The dealer never pays anything. The dealer is acting as the agent for Mazda North America and getting paid to do so.
 
Just wondering how many of you who had this cracked head/ blown gasket reported to NHTSA. Without many complaints, MNA isn't going to issue a recall.
 
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thought I had posted this earlier, but got my car back end of March picked up around the 28th or 29th, so far it's been running as it did before (I've been taking it easy on the throttle). Though once in a while, i think i smell something coming thru the vents. I can't place the smell, but it's only happened twice, but I will have to take it in soon for some other service, will have them check it out if it's happens again (plus i need to see if they will fix the spider cracked screen)
 
The smell may be from sealant or other compound burning off. It should go away very quickly.
 
Looks like a well informed group. I bought a 2018 CX9 in January and absolutely love it. Handles nice, plenty of power, and really comfortable. Giant leap forward from the 1991 Subaru Legacy I had been driving for a few years. About 3 weeks ago I started smelling coolant after the car was fully warmed up. Called a mechanic friend to have him check for bad hoses, radiator leaks etc. Long story short, I took it to a Mazda dealer a few days ago, TSB in hand, and sure enough I need a new cylinder head. They gave me an estimate of $6741 to complete the work, but when I asked if parts were available, they said they are back-ordered with no ETA. The car has 87K miles on it, so no warranty. I've put 3K gentle miles on it in the 3 months I've had it. I guess I'm wondering if anyone has helpful contact information at MNAO since I basically have a car that I shouldn't drive, that can't be fixed, and if I try to sell it in it's current state I'll probably lose half of what I paid for it. Can't really afford to buy another car any time soon, so feeling kinda PO'd.
 
Looks like a well informed group. I bought a 2018 CX9 in January and absolutely love it. Handles nice, plenty of power, and really comfortable. Giant leap forward from the 1991 Subaru Legacy I had been driving for a few years. About 3 weeks ago I started smelling coolant after the car was fully warmed up. Called a mechanic friend to have him check for bad hoses, radiator leaks etc. Long story short, I took it to a Mazda dealer a few days ago, TSB in hand, and sure enough I need a new cylinder head. They gave me an estimate of $6741 to complete the work, but when I asked if parts were available, they said they are back-ordered with no ETA. The car has 87K miles on it, so no warranty. I've put 3K gentle miles on it in the 3 months I've had it. I guess I'm wondering if anyone has helpful contact information at MNAO since I basically have a car that I shouldn't drive, that can't be fixed, and if I try to sell it in it's current state I'll probably lose half of what I paid for it. Can't really afford to buy another car any time soon, so feeling kinda PO'd.

You have a couple options here. 1) go to an independent shop for an estimate. The dealer is quoting you a crazy price for just a head job, that's only if the engine oil didn't mix with coolant and you only need a new head and not block too.. 2) call another dealer and get a new quote now that you know what is wrong and see how it compares. 3) get a used short block drop in engine assembly from a junkyard from a later model wrecked vehicle with a lot less miles and install. Should cost you about $3k to $3500 all in with labor . 4) call MNAO and ask for an assist with repairs considering the TSB. 5) Sell the car in its current state to CarMax, Carvanna,Vroom or similar. You will get top dollar regardless of the issue which isn't reported anywhere.
 
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