2018 Targa 4 GTS - on 2 separate occasions I have had issues with the heat/defrost (in reading other post it sounds like a change over valve (COV) failure. Car blow cold air for an extended period of time (longer than usual) then settles into what I would call normal operations (outside temps in low to mid 30s F). The coolant temp also jumped up a bit higher than normal and then cycled pretty hard between mid 100s and low 200s (see pic). Sorry for the bad pic, was on my way to work...

It isn't throwing any CELs or codes that I can see, just wanted the collectives thoughts on whether or not the dealership will be able to see the issue with a diagnostic or if they will be chasing a ghost.

Yes, I read all the heater failure threads...and most of them had hard failures so it was a bit easier to diagnose. Thanks for any advice or recommendations.

 

Hey Wes,

2018 Targa 4S here. Great rides, arent’t they?

I’ve had similar issues here but the a/c was my symptom, not heat/defrost like you. Perhaps our differences in latitudes explains that. I’m in TX.

Who knows based on these postings, right? However, Symptoms sound similar to yours -perhaps more acute here. On restart-up after stopping, the a/c would switch to heat and temp gauge would start quickly climbing up until “over temp / pull over”” warning would appear. Happened several times over weeks. It ended up being the water pump, valve block and cooling system vacuum system. It’s in the shop having all that replaced as I write.

There is a TSB for those issues for 2017 and 2018 models in US, Canada and Puerto Rico and PCNA has extended warranty to 10 years/120K miles for those issues on those models. Check in with your favorite P dealer for details.

Good luck.

PS: From your profile info it looks like you flew/fly. I recently hung up my wings after almost 30 yrs.

 

The first (and cheapest) thing I'd look into is your COV's.
They hardly throw codes and are prone to failure.
If you're remotely handy, you can diagnose them yourself with a 9 volt battery.
Regarding the testing procedure, there have been posts on here and the other forum on how to do this.

 

I had a very similar experience with my 2013 when the weather cooled.

In my case it eventually triggered the cooling system error and it was one of the pesky COV's.

 

Do you have a DIY on how to test the COV's. It might be handy to have on hand if needed

 

So...I never closed the loop on this thread...took it to the dealer, they hooked up diagnostics and drove it (b/c it was an intermittent fault) turned out to be a faulty valve body and water pump, both replaced by the dealer under thee 10 year warranty. So far no more issues.