Recent content by Mulligan

You're probably recalling a ticking problem that affected 2018 to 2021 (at least) models and was attributed to faulty hydraulic lash adjusters (HLA). There were some technical service bulletins about it, e.g., Bulletin 01-022/21 "TAPPING NOISE FROM ENGINE." Repair recommendations started with...

That's probably right. However, the temperature difference between active and deactivated cylinders likely adds stress to the head. That extra stress acting on the poorly designed (or poorly manufactured) cylinder head could be the straw that breaks the camel's back and results in a crack. If...

I was able to read "FZ" on the side of the dipstick on my 2025 when using a telescoping inspection mirror and a bright flashlight. The lettering isn't very prominent, so it wasn't easy to see. Per the 2024 manual, your 2024 probably uses A7, but based on my car and the 2025 manual, it looks...

As far as I know, the 8th character VIN method of determining whether a CX-5 has cylinder deactivation is reliable (L = without CD; M = with CD), but if you want another way to tell, look at the cylinder head. If it has one of the things in the attached picture on each end, the engine has...

A simple way to find out if your CX-5 has cylinder deactivation is to look at the eighth character of the VIN. If it's M, it has CD; if it's L, it doesn't have CD. For the 2025 model year, some S Preferred trim CX-5s have CD and some don't. At the time I was shopping (I bought mine at the end...

I owned a 2018 Grand Touring CX-5 (bought new) until about ten days ago. I have a low tolerance for risk, and what I'd read about cylinder head cracks, defective valve lifters, and occasional transmission problems in 2018s spooked me enough that I decided to replace my 2018 with a new...

It's good to know my 2018 has a low oil level warning light. A few minutes ago, I verified it by turning the car on without starting it and looking at the array of warning lights that are briefly lit up. There are so many of them and they're on for such a short time I had never noticed it. In...

(I wrote the following while offline and before reading Jack Rabbit's post. Turns out, we have similar thoughts.) In my opinion, an extended warranty isn't good enough. I suppose if you're confident your cylinder head will only give out while you're a mile from home on a grocery run and you...

Thinking back to the falling rocker arm problem of a few years ago, it's my recollection that there were only a handful of anecdotes (fewer than ten) posted by people who actually had that problem occur on their car. I'm pretty sure I've seen a lot more anecdotes about cracked cylinder heads...

They're threaded. The needle nose pliers method of unscrewing them works pretty well.

An earlier report in a related thread also lists PYY4-10-SJ0 as the replacement cylinder head for a 2018. Per realmazdaparts.com and mazda-parts.com, PYFA-10-100E is the part number of the cylinder head for the 2018 CX-5. When you look up PYY4-10-SJ0 and run the checker to see whether that p/n...

I just noticed there's a substantial fin cast into the head over at cylinders 1 and 2 (red arrows). Given its shape, I wonder if its primary purpose is something other than cooling and strengthening, but surely it provides both in the area of cylinder 2 that is symmetrical with the area that...

What to make of there being only 2mm of material at the location of the crack? I have a couple ideas—barely more than guesses, but informed by a dusting of logic, experience, and common sense, I hope. Guess 1: Mazda used the occasion of revising the cylinder head for CD as an opportunity to...