CX-5 CCV issue

[aen17]

My CX-5 2018 AWD, with cylinder deactivation, non-turbo, gas, touring seems to be running cool. It will run with CCV closed until it gets to 122°F, which is in the upper limit of the "blue zone", then it will open and immediately cool down. As a result on a cold day of 13°F it will not turn off the blue light for over 20 min of idling, and if I start driving it, it would take even more since the cold air flow is cooling the radiator with warm coolant in it.

I know it, because I was feeling the radiator hoses - they become hard and warm at around 122°F. I verified the temperature with a scanner, so the temp sensor on the CCV seems to be working fine if the freezeframe data feeds off it.

When I drive it normally, it would take prolonged periods of time to drive - like 40 min to get it to 155-165°F and over an hour of city traffic to get to 188°F if at all.

My normal commute is not expressway, it is short of about 5 miles some days and some with 2 miles at a time. I have no check engine light and no P0126 code, which I attribute to the shorter commutes I have. Mazda stealership refuse to honor the service bulletin in my case

https://static.nhtsa.gov/odi/tsbs/2024/MC-11003350-0001.pdf

I can't wait on them doing paperwork, so I am wondering which part I have to use as a replacement:

PYFD-15-16Z or PYFD-15-16ZA.

Both are stated to be exact fit for my vehicle at the mazda parts website. It is steep at $450, but I seem I don't have any other choice since Mazda will not honor and fix the mistake they did with choosing this crap for CCV. I also heard there is a service kit, so you don't have to buy the complete CCV set? Anyone knows its part number?

 

[Mazdiod2]

Usually the part with extra digits supersedes the original part, so you would want the one with the "a" on the end.

The STB you posted has this chart on page 6 of 7:

Parts Number Description Qty. Notes
PYY2-15-SA1 THERMOSTAT SET

Is that part number for the service kit?

 

[SimpleCanuck]

As per the service bulletin, the check engine light needs to be illuminated for the warranty to be honoured. In my case (very recently), the light did not come on until I took it onto an expressway and got up to speed (60-70mph). So that is my suggestion: Drive it on an expressway.

 

[aen17]

This is o

Usually the part with extra digits supersedes the original part, so you would want the one with the "a" on the end.

The STB you posted has this chart on page 6 of 7:

Parts Number Description Qty. Notes
PYY2-15-SA1 THERMOSTAT SET

Is that part number for the service kit?

No, there are variety of models listed on the STB. Not all of them use the same part number. As I already wrote, those the alternative parts that are exact fit. If you don't know it is ok to say you don't know.

 

[aen17]

As per the service bulletin, the check engine light needs to be illuminated for the warranty to be honoured. In my case (very recently), the light did not come on until I took it onto an expressway and got up to speed (60-70mph). So that is my suggestion: Drive it on an expressway.

Do you know what are the factors that cause this P0126 to come up? The advice of driving it on expressway seems illogical to me - you drive it in high rpm, therefore it is bound to heat up more. I already stated that it opens up prematurely, not that it is stuck closed.

 

[SimpleCanuck]

Do you know what are the factors that cause this P0126 to come up? The advice of driving it on expressway seems illogical to me - you drive it in high rpm, therefore it is bound to heat up more. I already states it opens up prematurely, not that it is stuck closed.

My evidence is merely anecdotal and thus, a suggestion. Before the light came on, I had the abnormal gauge behaviour for 2 weeks, all without driving on an expressway.

 

[sinistriel@]

For those curious these are the set conditions for the 18 CX-5 with Cylinder Deactivation.

 

[aen17]

For those curious these are the set conditions for the 18 CX-5 with Cylinder Deactivation.

Thank you so much! This is exactly what I needed!

 

[aen17]

So, I had it tested in a Mazda dealership. According to them, thermostat opens at 155°F and it is allowable to open at that temp. I checked it with a scan tool to open at 125°F, checked by feeling the hose too, which matched. Airflow dampers work fine and are not stuck open. I drove it for 50 miles yesterday at 28 °F mixed city and expressway and when I parked it it was at 156°F. I fail to see how this can be OK. Yet, there are no check engine lights, no codes come up, no excessive fuel consumption. What do I do? Another dealership?