Change Over Valves question
04-23-2021, 10:08 AM
#1
Change Over Valves question
2014 C4S Cab
Got in my car this morning and no heat. Quick google search leads me to believe its a COV. Youtube video shows location is just below spoiler inside passenger fender, very easy to get to. From what I can tell, there will be blue vacuum line run to all 8.
Called dealer, they have 6 in stock, $50 each. Definitely doing the the heater one, but I have read the others have had other bad ones without even knowing it.
My question, should I just do all 8 and not look back? I own a shop, have a lift, and am very capable. Just curious if I am wasting time.
What other symptoms may my car have with a bad changeover valve that isn't throwing a code?
Thanks!
Got in my car this morning and no heat. Quick google search leads me to believe its a COV. Youtube video shows location is just below spoiler inside passenger fender, very easy to get to. From what I can tell, there will be blue vacuum line run to all 8.
Called dealer, they have 6 in stock, $50 each. Definitely doing the the heater one, but I have read the others have had other bad ones without even knowing it.
My question, should I just do all 8 and not look back? I own a shop, have a lift, and am very capable. Just curious if I am wasting time.
What other symptoms may my car have with a bad changeover valve that isn't throwing a code?
Thanks!
04-23-2021, 10:21 AM
#2
Rennlist Member
If you have the means and the time....... I'd say do them all.
There's a write up on here somewhere showing all their locations.
There's a write up on here somewhere showing all their locations.
Last edited by CSK 911 C4S; 04-23-2021 at 10:22 AM.
04-23-2021, 02:44 PM
#3
Rennlist Member
This is a good place to start. https://plenums.blogspot.com/2016/10...-overview.html
If you have PDK, there is one above the transmission that I understand is impossible to get to without dropping the trans. There are two tucked up into the passenger side above the engine that require very small hands or ripping out the old tubes and using new ones that slide more easily. I only changed one of those because it was so tight. There’s another one farther towards the front from those two as well. That one I won’t touch either. There are also two connected to the airbox.
If you have PDK, there is one above the transmission that I understand is impossible to get to without dropping the trans. There are two tucked up into the passenger side above the engine that require very small hands or ripping out the old tubes and using new ones that slide more easily. I only changed one of those because it was so tight. There’s another one farther towards the front from those two as well. That one I won’t touch either. There are also two connected to the airbox.
04-24-2021, 12:10 PM
#4
The YouTube vid you saw on replacing the heater one was probably mine. Easy replacement, but small hands would help. Love to do them all (if only I had a shop!), but as fnckr says there are a couple that will require dropping engine/tran. 
04-25-2021, 07:24 PM
#6
I agree. Its almost as if they designed a car with just one thing that needed one of these valves a long time. Then they added another option. Then another. Then another, and never bothered to change the design. Now there's 7-10 lol
Why not just add some sort of vacuum manifold and send all these lines there with multiple banks?
Why not just add some sort of vacuum manifold and send all these lines there with multiple banks?