The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

Controlling the GT350 Exhaust Valve

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Was on the AWE website and didn't see option specifically for GT350. Did you order the Mustang GT one?
https://www.awe-tuning.com/switchpath-exhaust-remote

I ordered this exact one. The only Ford car it says that it fits is the Focus RS. They don't mention the GT350 anywhere but it definitely works. They should add it on their compatibility list because they'd get a few more sales out of it. It is 100% compatible with our cars.
 
The Grimm Speed modules work on the RS and GT350. The valve is used by other auto manufacturers as well.
 

FogCitySF

2017 GT350R
Was on the website and didn't see option for GT350. Did you order the Mustang GT one?
https://www.awe-tuning.com/switchpath-exhaust-remote

I ordered this exact one. The only Ford car it says that it fits is the Focus RS. They don't mention the GT350 anywhere but it definitely works. They should add it on their compatibility list because they'd get a few more sales out of it. It is 100% compatible with our cars.

Awesome! and thanks! Let us know where you end up mounting the remote for easy access. I'll probably order one of these too.
 
That looks like a winner. Just double check that when in track mode and at WOT the valve doesn't open.

I have double checked and all I have to say is....wow. It's so quiet! I did a few 1-2-3 redline pulls and it made me realize that none of us have heard how our stock mufflers sound at WOT. It gives the car a sort of deep growl and rumble. I kind of like it! Felt like a completely different car based off of the sound alone. I can't wait to try Laguna Seca now.

Conclusion: It works great!
 
Here is installment 2 on this post

As I had mentioned above, variation 2 on this basic solution is a version that does not require cutting into the wiring harness.

It turns out that Ford sells all of the connectors found in our cars. In this case, we are interested in both the female and male counterparts of connector C215.

Here are the Ford service part numbers:
Male - ???
Female – 3U2Z-14S411-TJA – Motorcraft Part Number - WPT-516

Here is what the female connector looks like
View attachment 5128

I have been and will continue to look for the male part number. No luck yet in finding it.

Ford calls these connectors “pigtails”. Since this connector can be employed in multiple places, they are unable to supply the correct color coded wires. They come with generic black or green wires in the spec’d out gauges.

Here is what a typical “pigtail” looks like:

View attachment 5129

So you get the connector with wires already crimped with the correct terminals already pressed into the connector, some solderable butt connectors, and heat shrink wrap. This is a 3 pin connector above.

A little side note on Ford Connectors:

Even though these connectors have Ford service part numbers, they also have Motorcraft part numbers. Turns out that Motorcraft actually handles all Ford connectors. The Motorcraft part number starts with WPT- and some number, three or four digits in length.

Motorcraft has a “pigtail” catalog. Can be downloaded from here as a pdf:
http://www.fordservicecontent.com/pubs/content/connectors/images/connectorcatalog.pdf

Only problem with this catalog is that it is somewhat dated. Came out in 2016 so not all of the connectors for the 2015+ models are in there. You will find pictures of the connectors which serves to help in identifying the connector you are looking for. Under each picture, you have the Ford service number and the Motorcraft part number. Way at the end, they also list where/how the connector is generally used. Pretty generic but could help in identifying which connector you are looking for.

I will provide you all with something that I put together in another post which I believe is very useful in making any wiring job a lot easier!

One other note. Most (90%) of connectors are female. Like the connector for the exhaust valve actuator. The female connector plugs into a male counterpart molded on the actual exhaust valve actuator.

Another example is the male speaker connector. I have the 4inch screen display, Sync 1 or what ever it is. Great radio with good power and super low distortion but the speakers really suck. So I replaced them with Harmon Cardon speakers. Problem is the after market speakers come with solder terminals. I did find the male counterpart to the Ford speaker connector and with a male connector soldered to the speaker, everything looks factory! These male counterparts are really hard to find but they do exist!

Another side note:
These connectors are expensive at $20-30 or more each. Sometimes, it is cheaper to buy the complete harness. For example. I had to rewire all of my external lights to comply with EU regulations. Yellow side markers, yellow rear blinkers, and a rear fog light (I also added front fog lights). There was no way that I was going to replace the rear tailights with those EU clear ones. Mine are factory red with super bright yellow LED's inside.

Turns out there is a sub-harness with a designation “13142”, its on the connector picture above with each connector . Turns out that the whole harness costs $28.99 and it has 10-15 different connectors on it. The harness also has the correct color coded wires in it. So for $28.99, I got color coded factory wire and all the connectors I needed. Buying these connectors individually would have cost $100-150 and I would have had generic black and green wires at all of the connectors. Even the largest harness in the car which is the body harness only costs $200. So well worth it if you needed a lot of connectors and want color coded wiring.

Another example are the “pigtail extensions” VoodoBoss sourced. Each connector alone would have cost $20+ each. By buying the “extensions” you get the correct color coded wire and these are wrapped with a special heat shield with two connectors for $15 each.

So what we are going to do is create a “plug” of sorts that will go between the male and female parts of the connector at C215. This will allow us to splice into the circuit without having to splice into the factory wiring as in version 1 above.

The more work involved part is that you have to make this “connector” yourself. Basically, you will take the male and female connector that you just bought and create a pass through connection on all pins except for pins 2. Here is a simple picture of what it will look like:

View attachment 5130

Let me explain “more work”. You will need to cut down the leads on the “Pigtail” on both connectors to lets say 1.5 inches. Make them all the exact same length, measure, mark, and cut. This will save on a lot of headaches soldering the two ends together. Strip off exactly the same amount of insulation off each wire. Measure it, mark it, and use a quality wire stripper. Use the supplied solderable butt connectors and connect pin 1 to pin 1, pin 3 to pin 3, pin 4 to pin 4, etc. Do all 10 pins except for pin 2. Pin 2 is what we are splicing into.

This will take a lot of patience and playing around. Idea is to keep the leads as short as possible. Tape up each splice. It will be impossible to slip on the heat shrink with very short leads. As you solder the leads, the heat will shrink the tubing since it’s so close to where you are soldering and you will not be able to slip the heat shrink tubing over the soldered joint.

There is another way but will require a lot of playing around. You can actually remove the wire and terminal from the connector. Use a medium size safety pin go in from the back of the connector in each cavity and use the pin to press down the tab that holds the terminal in place and pull it out. (Motorcraft sells special tools for this. These tools are in the Pigtail Catalog). Like I said a lot of playing around with very gentle pulling on the wire. Once the terminal is out of the connector, you can slip on the shrink tubing and heat it up to seal the joint and push the terminal back into the connector. Pay attention to the terminal orientation as you pull it out so that it goes back in with the same orientation. This is how you would repair a connector by the way.

Another option is to pot the whole connector (the one that you are making) in epoxy. When everything is soldered up, create a form with masking tape leaving the top open. Mix up the epoxy and fill the cavity. One serious word of caution, seal off the whole back face of the connector with caulk or the like. If you don’t the epoxy will flow in from the back of the terminal cavity and gunk up the terminal cavity and will interfere with the ability to plug one connector into the other. The epoxy does (when hard) keep the whole thing rigid, no wire wiggle when handling the built connector. Would also allow for really short wires. You won’t have to insulate the solder joints because the epoxy will do that.

So you see you can do this without splicing into the wiring harness by creating your own wiring harness with connector for the switch. Like I said, slightly more cost (for the two connectors) and a lot more work but by unplugging the connector you just made, everything is back to OEM. This one is fairly easy, there are only 10 pins here. Keeping the leads short is the key. Longer leads will simply the job but also make your connector bulky and harder to hide.

In the next version I’ll show you the ultimate solution but will be harder to make and cost a bit more.

I did this today. Thanks for posting the info.f9f1a85e54b99d16f0c6a65b77147570.jpg
 
4
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
East Georgia
I purchased this car a little over a year ago and have had a ton of fun with it. Pretty much everything that I have owned has had the exhaust modified. Harleys, Can Am Spyders, Polaris Slingshot, and even a Toyota Tundra. The sound of the Voodoo FPC was the selling point.....until I found out the computer still controlled the active exhaust. Been bugging me for over a year until I finally took some time and researched the fix. Dummy plugs, nope. Separate controller, nope. Just tapping into pin 2 wire with a push on/push off switch, hidden in the upper left corner of the glove compartment, now puts a smile on my face every time I start it! Now it sounds like it should all of the time and I can put it back to stock with the push of a button.
Loud pipes saves lives (Harley saying).
 
Just attempted this on my 2018 and while it does keep the valves from moving, I'm getting a drive mode selection not available after about 10 seconds or so. It's almost like it's looking for some sort of signal response or something and not getting it.

With the switch closed it works as normal with no issues. But when I open the switch it allows me to select the drive mode without effecting the exhaust valves as it should per the instructions, but then throws up the drive mode not selectable error on the dash. The confusing part is that I can put it into track mode, let it sit for 30 seconds or so, move the switch to disconnect power to the solenoids and within seconds the car will display a drive mode selection error without me even trying to adjust the exhaust or drive mode itself.

I'm using a 2 blade switch instead of a 3 blade, so not sure if that's causing an issues but it should simplify things if I'm correct, but I'm connected to the violet wire with the brown stripe on pin 2 as the original post suggests.

Car is an early production 2018 GT350 if that matters, but seems cars built before and after mine seem to be able to use this mod without issue. I can only imagine that there's some sort of change to the way the 2018's work that's causing an issue with this as I've seen 2017 vehicles allow it to work, and I've seen that 2020+ cars seem to be able to just pull the fuse to "lock in the mode" without a drive selection error. Has anyone been able to get this to work with a 2018/2019 model?
 
Last edited:
4
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
East Georgia
Mine is a 2020. When I start it up, I will get that message for about a second and then goes away. Actually kind of like it as it lets me know which way the exhaust bypass switch is set. So, you are seeing this message all of the time?
 
Mine is a 2020. When I start it up, I will get that message for about a second and then goes away. Actually kind of like it as it lets me know which way the exhaust bypass switch is set. So, you are seeing this message all of the time?

I get two alerts "exhaust mode selection not available" and "Drive mode Selection Not Available". They go away, but I'm unable to select drive modes and without being able to select drive modes I'm unable to put the car into Track mode to access the track suspension setting. Doing some research it appears that something changed in 2020 as other 2020 owners have reported being able to simply go under the hood and pull the fuse to the exhaust valves and still retain driving mode control. This has been confirmed by other 2018 owners not to work.

 
Has anyone been able to get this to successfully work with a 2018 specifically?

Perhaps it's the switch I'm using, although I don't see how that could cause as the end result is the high voltage line being disconnected to the solenoids on demand at the C215 connector all the same. I'm beyond frustrated that the functionality seems to work for 2016,2016, and 2020 models but for some reason 2018's and possibly 2019's operate differently.

I wonder if my car being a Canadian export initially might have any effect as well?
 
Tried a new switch and still getting the same results.

Switch on. All is good and all works fine. Turn switch off and car throws "drive mode not selectable" within about 3-5 seconds.

According to my voltmeter pin 2 on connector C215 carries a constant 12 volt signal back to the two exhaust valves. My understanding is that the PCM then sends a signal to the valves down the violet wires and through pin 34 at connector C212 and C213 in the same passenger footwell. The only other wire we see in the provided diagram is the ground wire at the actual valves themselves. Is it possible that the PCM is monitoring that 12 volt feed into the exhaust valves somehow? It must be if the wiring above is accurate. Does anyone else have 2018 specific GT350 wiring schematics for the PCM or exhaust valves?

Maybe on the 2018 I need to bypass the solenoids completely and run a jumper wire all the way to the grounds to keep the system happy? It's been a while since I've read wiring schematics and these newer can-bus systems are more complicated than what I'm used to. Would like to get some feedback before I try some shiznit and start popping fuses, relays, and god knows what else. At this point I'd just buy the AWE system, but I'm not 100% confident it will work and the price is now up over $350.

upload_2018-9-15_12-55-59.png
 

TMO Supporting Vendors

Top