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Controlling the GT350 Exhaust Valve

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I had posted in the thread on the reverse camera that I would post a solution to the exhaust valve. I will make this a multi-part post offering an overview and multiple solutions ranging from very cheap to more involved and elegant but also a tiny bit more expensive.

So first a quick overview of the circuit we are dealing with:

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The exhaust valves in the back are solenoids. The PCM controls when the exhaust valves are opened or closed. As we all know, it does what it wants and sometimes at the most inopportune time. The PCM sends a very low voltage and amperage signal to the coil of the solenoids to activate them. This activation allows a larger current to flow from the battery junction box through to the solenoid actuator that opens and closes the exhaust valve - upper right.

Quick explanation of the Grimm Exhaust Valve Defeat Module. The module was designed for people who install exhaust systems without exhaust valves. When you unplug the exhaust valve at connector C4466 and C4467, it creates an open circuit that the PCM sees on pin 11 which is the line that the PCM uses to control the exhaust valves. The PCM detects a fault and throws a DTC code. So the Grimm solution tricks the PCM into believing that there are exhaust valve solenoids out there by using a resistor with the same resistance as the original exhaust valve solenoid coils. Obviously you need 2 because they are plugged into the wiring harnesses where the 2 exhaust valves used to be.

I believe it was VoodoBoss who sourced the harness extensions which are shown between C345 and C4467 on the driver side and C346 and C4466 on the passenger side. The Ford service part numbers for these extensions are:

FR3Z-14A411-H for the drivers side
FR3Z-14A411-J for the passenger side

FR3Z-14A411-J is no longer available but both are exactly the same. Only difference is that FR3Z-14A411-H is a little bit longer. The harness (ea) cost approx. $15 So with the Grimm modules and 2 extension harnesses you are in for approx $70

I believe that it was VoodoBoss who cut the chase and said basically, the only thing that “we” need is the ability to make sure that the exhaust valves stay closed on a track with noise restrictions. My paraphrase :)

So here is a quick and dirty solution with two variations. Variation 1 costs less then $15 and about an hour of work but requires cutting into a wiring harness. Variation 2 costs around $60 and will require about 1-2 hours worth of work but you will not have to cut into any wire harness. It’s a plug and play option that when unplugged, returns the wiring to the way it came from the factory. Both use a simple toggle switch with two positions, OEM operation and exhaust valve closed. You can always open the exhaust valve via the switches on your steering wheel / menu in OEM mode or via the center console if you have the electronics package.

So variation 1 for less then $15

Bill of Material
-------------------
12v/15amp toggle switch
8 feet of 16 gauge wire (I would use red since its power on both leads)

This will require splicing into a wiring harness.

If you follow the leads from pin 2 on the exhaust valve solenoids, you see that this is where the high amperage power enters the solenoids. If you trace the leads up to the Battery Junction Box, you will see the wire runs through an inline connector C215. Inline connectors consist of a male and female connector. It’s simply an inline connector. Here is the connector info and the pin-outs:

upload_2018-9-15_13-1-34.png

You can see from the circuit above that the wire we are interested in is on pin 2. The good part of splicing into this connector is that it’s in the passenger compartment (no weather or heat issues) and is located behind the kick panel in the passenger foot well.

Here is a picture of where it is located:
upload_2018-9-15_13-3-52.png

So what you need to do is find the connector, strip back the insulation that wraps the harness at the connector, find pin 2 – it will be the violet wire with a brown strip – same on both male and female connector. Cut the wire (either side) and solder in a 4ft piece of 16 gauge of wire to each cut end and seal up the splice with heat shrink tubing. Re-wrap the connector.

Create a harness by wrapping your 2 spliced in wires with electrical tape. Route your newly created harness back behind the dash board over the sun glass tray or where every you are mounting the switch.

I would find a small plastic hobby box that fits in the back of the sun glass tray and mount the switch there.

The switch will have 3 contacts on it. Check it with a VOM but typically the center is common and each of the 2 outside contacts are either on or off. Solder one wire to the center and one to one of the end contacts. Mount the switch, DONE!

Here is a simple schematic of the circuit you are adding:

upload_2018-9-15_13-6-28.png

Here is what it is doing:

Switch in position 2 above is OEM mode. Nothing has changed. The power flows down from the Battery Junction Box through connector C215 normally just as Ford designed it. Exhaust valve does whatever the PCM wants it to do.

Switch in position 1 breaks the line and does not allow the power to flow to the exhaust valves. The PCM see’s the actuator coils (nothing has changed on that end) and switches away as it wants but nothing happens because the higher power needed to run the actuator isn’t there. PCM thinks that it’s either open or closed and thus no DTC codes but in reality the valves remain closed. With no high power flowing to the exhaust valve, they remain closed.

And you control it from the dash (or where ever you mount the switch) without having to do a thing like switch harnesses, or plug in resistors.

You could technically, keep the switch in OEM mode and as you approach the station on the track that measures sound levels, switch the vales off and when you pass the station turn the vales back on :)

In the next post, I will show you how you can do the exact same thing as version 1 here but without having to splice into the harness. It will cost a bit more and required a little more work but I believe is worth it.
 
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...And you control it from the dash (or where ever you mount the switch) without having to do a thing like switch harnesses, or plug in resistors.

You could technically, keep the switch in OEM mode and as you approach the station on the track that measures sound levels, switch the vales off and when you pass the station turn the vales back on :)...
This write up is excellent - well done! My preference would still be to make a harness that just plugs in, but maybe that's just me being lazy.

What the market really wants, though, isn't a switch. It's a GPS-powered switch. As you approach the mike location, it closes the valve and after you've passed it by a safe distance, it opens it again. Lap after lap. Somebody should make one.
 
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If you have programming skills, it'd be relatively straightforward to plug a GPS receiver into a Raspberry Pi running an app that flips a switch based on whether you're inside or outside a geofence box. If you build blk2017's switch setup so it has a control relay as well as a manual switch in it, then you're golden.
 
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
upload_2018-9-23_8-26-43.png

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:

upload_2018-9-23_8-27-55.png

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:

upload_2018-9-23_8-33-39.png

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.
 
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Removing the Exhaust Valve Relay

As to the solution with removing the relay that feeds power to the exhaust valve solenoids, technically it should work without throwing DTC codes or disabling Drive Modes. The theory was correct but the implementation is wrong. Before I post the solution I would like to try it out. I will post back if it works. Should be a relatively simple solution if it works and you really want to disable the exhaust valves by pulling the relay.
 
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Found this:

It's entirely possible that the 2018 valves in the video are more nuanced than the 2016 valves in our GT350's. Certainly, in the 2018 case, there is more to Exhaust Mode than "open" and "closed". Even if the GT350 valves are simpler, you can be sure that Ford was working on the nuanced version of the valve control when ours were designed, and our valves are wired up just like the later ones. Like any other ECU controlled valve on the car, there's a control circuit that moves the valve and a feedback circuit so the ECU knows if the valve is delivering what it commanded.
 
Found this:

It's entirely possible that the 2018 valves in the video are more nuanced than the 2016 valves in our GT350's. Certainly, in the 2018 case, there is more to Exhaust Mode than "open" and "closed". Even if the GT350 valves are simpler, you can be sure that Ford was working on the nuanced version of the valve control when ours were designed, and our valves are wired up just like the later ones. Like any other ECU controlled valve on the car, there's a control circuit that moves the valve and a feedback circuit so the ECU knows if the valve is delivering what it commanded.

Ok but that is not a 2018 Mustang GT. Nor is it a GT350.


Sent from my iPhone using Tapatalk
 
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Ok but that is not a 2018 Mustang GT. Nor is it a GT350.
Sent from my iPhone using Tapatalk
This is from Borla's YouTube channel so I had no reason to doubt it's authenticity.

If not a 2018 Mustang GT with Active Exhaust, then what are the valves from?
 
Has anyone done this in the Bay Area yet? If so, looking for someone to do the switch solution.

I haven't done this but I just bought this and plan to install it this weekend. There is at least 1 other GT350 in the Bay that did this and had success (with the addition of Laguna Pipes) at Laguna Seca. It makes it so that the exhaust is only controlled by an on/off switch via wireless remote. The drive modes still work but they do not change the exhaust mode. It was $183 when I bought it a couple weeks ago but it looks like the price jumped about $50 after I bought mine.

https://www.awe-tuning.com/switchpath-exhaust-remote
 
I just installed my AWE SwitchPath today but haven't had a chance to take it out for a drive because NFL playoffs and beer :-D

The box it came in was nice, they gave me a lollipop :D
IMG_20190101_125128-2133x1600.jpg

The install was straightforward but DAMN! Unplugging the exhaust actuators was such a PIA. Good thing I won't have to do that again. The remotes work perfectly and I'm going to mount one up right next to the shifter and keep the other as a spare.

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IMG_4794-2400x1600.JPG
IMG_4799-2400x1600.JPG

I'm sure the Gimmspeed ones work fine but I like the remotes because I can open/close them whenever I want and never have to go back there and plug/unplug anything anymore. With the AWE remote, I can keep the exhaust open while I change drive modes, I can keep it open in 6th gear, and I can keep it closed while going WOT.
 

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