sbiscuit

I'm having the same issue with no heat. Dropped off '14 C4S at dealer this afternoon. They mentioned that they think it's the solenoid controll panel might need to be replaced?? We will see.

sbiscuit

Dealer confirmed it's a COV failure--it melted itself along with the part below. Dealer had COV but not the part below. Hopefully it will arrive from ATL tomorrow.

GTW4CG

Well, as I posted above, the passenger side heater started working again on the drive up to the dealer. Dealer has had it for a day, and can't duplicate the problem, can't find any error codes, and can't find anything that might have caused the problem.


Oh, well. I wanted an oil change and a car wash anyway, and I got to drive around in a Cayenne Turbo for a couple of days. And the Gremlins are recorded in the service records.

CSK 911 C4S

Oh Noooooo.

Please get as much info on this as you can especially where it was located and why it melted.

plenum

Can you provide any other detail? To my knowledge, this would be the first case of a COV melting.... The most common failure is caused by moisture build-up in the COV, leading to a failure where the valve is stuck in one position or another. I don't believe there is anything in a COV that would cause heat. However, as it is in the vicinity of the engine bits, perhaps it was out of place and came in contact with something producing enough heat? Totally confused by what the dealer told you - "melted itself"?!!

technivoro.us

I just had the valve replaced on my '14 C4. Here's what the tech said on the report - "FOUND SWITCH OVER VALVE MELTED (SEE ATTACHED PICTURE), DUE TO INTERNAL SHORT."

I don't have the picture that's referenced. I'll see if I can get it from my service advisor.

Jabs1542

Is it possible we're talking about apples and oranges here? Isn't a Change Over Valve pneumatic, while a Switch Over Valve is electric? I'm asking here because I thought the COV was operated by vacuum pressure in a pneumatic fashion.

BTW - It would be nice to hear the story how the 993 saved your life, and it really hurts to see your avatar (though mine was from a rebuild of a V12 that was painful in its own right).

technivoro.us

They replaced part 7PP-906-283-F, which is an electrically controlled pneumatic valve, as well as 991-612-944-00, a wiring harness. I've asked for the picture they mention in the invoice. I'll post it here if I get it. My car had the same symptoms as others in this thread. Air blows, thermostats seem to know the temp is low, but air isn't circulating through the heater core to warm up.

Here's the carnage of the 993 wreck. Story is pretty brief. As the Flickr page says, "Two days before my wedding, a kid driving his mom's Mercedes decided to pull out in front of me.

Luckily, Porsche builds a strong little car. 55-0 mph in 30 feet, and the doors still worked, and it was able to be pushed off the road by hand."

Airbag deployed, and the combo of me hitting it and it hitting the dashboard was enough to crack the windshield. I had a nasty bruise across my chest from the belt and mild burns on my arms from the airbag but walked away under my own power.

The hit threw the Mercedes about 30 or so feet sideways on top of a fence and bent it pretty badly. Rear seat passenger was unconscious and broke their arm and some ribs.

Car was totaled and I didn't have the funds or space 11 years ago to buy it back and rebuild into a track car, but I bet that's what happened.

Jabs1542

Wow, that's pretty amazing from what looks like a lite weight sports car - with very little up front. Good story, good to hear the doors worked and you walked out on your own, quite a testament for these cars.

Also looks like you got close to 136K miles, good on ya

Chris C.

My Sept '12 build 2013 has had one heater COV replaced so far...

Is anyone else paranoid now listening for changes in their car? Driving last weekend I was sure my PSE was stuck on...but I think it was just a right foot problem!

Hurricane

I do the same thing...

Pavegeno928

Heat stopped working...just cold air blowing. Will take it in in two weeks when I get the oil changed.

rcg412

Had same problem. Was cov valve. Took like 30 mins to fix on a turbo.

Pavegeno928

Heat started working again yesterday. Odd. Getting into the 40s in the morning in Germany. I have an appointment Monday and will see if it is acting up.

Caoticvet

Just had mine replaced. They said mine was cracked. 2013 CS covered under CPO.