I just did this mod as well. I did a slightly different method, instead of using the plastic T's I used the rubber ones made for vacuum line, I think they were 7/64th or something like that. I simply cut the line the the frps right where I wanted the T and left the original line on the solenoid and put it on the other side of the T. It fit very snug and I have not glued or zip tied anything and have no problems. Its a little easier than using the zip tie.
How To: Eliminate Boost Drop Off (eliminate boost solenoid)
- Thread starter metaman
- Start date
i have a feeling its the EGR delete. In your pictures it looks like the previous owner did an EGR delete and eliminating all the wires on the side of the charger is the main reason ppl usually do them. Only problem is without it in a tune it can set ur check engine light off and make it run like crap also its an inconvienince the previous owner did it becaus now its too hard to tell if it was even done correctly id look into some diagrams of deleting wires in the egr delete and see if it was done right.
The egr delete and the removal of those solenoids should not effect the performance like he is complaining about. The lack of egr will just cause a check engine light. The dpfe sensor monitors egr and exhaust pressures and since there is no egr te not needed. If they already did a boost bypass then there is no need for bypass solenoid. I'm not saying the job was done pretty but as long as a tuner put all of that into a chip to account for it hen I would say you have other problems.
I just did this to my car today and the write up is perfect. My car feels better when its at full boost. Thank you metaman for this tutorial.
I want to make sure I'm understanding this correctly. So basically you're tieing the top port of the bypass actuator into the vacuum-only line that runs to the FRPS and eliminating everything else boost-bypass related? How does the actuator function now that it is only seeing vacuum?
The line that runs to the FRPS is not vacuum only. It comes off of the bottom port on the blower and sees both boost and vacuum. When you tie this into the upper port on the actuator is pushes the bypass actuator rod down under boost and pulls it up out of boost.
Got it, I read it wrong... So this mod ("BOOST BYPASS" Installation Instructions for the 2003, 2004 Supercharged Mustang SVT Cobra) is doing what exactly?
OK now I have a problem with this mod. I performed this mod a few months ago and did not notice a huge change except a lot of sputtering here and there, I rarely drive the car. I had a cheaper quality a/f narrow band gauge that monitors the factory O2 sensor. It showed switching so i figured no vacuum leaks maybe just my fuel going bad from sitting for months. I was going to have it checked by my usual tuner, I just couldn't get over the thought that the only thing I changed was performing this mod. I decided to ditch the narrow band and upgraded to a Innovate Motorsports wide band. Well I went racing today and to my surprise about half way down the track I looked at the gauge and saw 16.7!!!!!! I was freaking. I pulled plugs to inspect. No detonation but they got hot, the ground electrode was turning white. I looked over and over for a vacuum leak, I know i have good fresh gas, I even added 5 gallons of C16 from the track just to be sure. Per the instructions on this thread to leave it alone,I still couldn't get over the lower port on the boost dump valve just being open to atmosphere. With the car running at an idle there is no vacuum on that port. (Here's the best part) when i would blip the throttle, sure as sh*t I felt vacuum. So I don't know if my dump valve is bad OR there needs to be an edit to this modification to plug off the lower vacuum port on the dump valve. Anyways I plugged the port and made another pass my A/F stayed 12.5-7 the whole way down the track and I picked up .5 sec. Please someone verify what I'm saying is correct and if I am please everyone who has performed this mod plug the lower port.
Bump. Wondering if anyone else experienced the same?
This is odd, because typically a boost leak would yield a rich condition not a lean condition. When you lose metered air the car is still injecting fuel assuming the metered air is still entering the motor.
I thought that the line going to the valve was coming from the bottom port on the S/C.
He verifies that this line is boost and vacuum...
I have the opposite 'issue'. Did this mod about a week ago and the principle is sound. This mod is listed in several other places with similar instructions. So I don't know what to tell you there.
I was driving around and the mod worked as described as far as faster boost/throttle response. I did have to reset the computer right after (threw an 02 slow response code on both banks) which I think had to do with the change of air/temp at low load (improper boost bypass was done before)... I don't know if these cars learn(?) or not but I cleared it and reset the computer. And it hasn't popped up since.
But to my surprise a little whiles later I noticed a very noticeable but slow PSSSSSHH almost like a vacuum leak everytime I let off the throttle after giving it a bit of a pull. (Going ahhhh crap of course)... I've had lots of vacuum leaks/unmetered air problems with this car before. After revving it a few times I realized that it was definitely air being discharged out of the boost bypass valve... You can feel it hissing out. Almost like a blow off valve. I don't feel any vacuum in there though when idling. I don't know anyone else noticed this or not.
That's just my experience though so take it for what it's worth :shrug:
I was driving around and the mod worked as described as far as faster boost/throttle response. I did have to reset the computer right after (threw an 02 slow response code on both banks) which I think had to do with the change of air/temp at low load (improper boost bypass was done before)... I don't know if these cars learn(?) or not but I cleared it and reset the computer. And it hasn't popped up since.
But to my surprise a little whiles later I noticed a very noticeable but slow PSSSSSHH almost like a vacuum leak everytime I let off the throttle after giving it a bit of a pull. (Going ahhhh crap of course)... I've had lots of vacuum leaks/unmetered air problems with this car before. After revving it a few times I realized that it was definitely air being discharged out of the boost bypass valve... You can feel it hissing out. Almost like a blow off valve. I don't feel any vacuum in there though when idling. I don't know anyone else noticed this or not.
That's just my experience though so take it for what it's worth :shrug:
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So your pretty much experiencing the same issue I have. I actually think that I have heard that noise I just thought it might be normal with this mod but honestly didn't dig into it. You are getting slow response code because its causing a lean condition. Now that I got the car out of the trailer and back at my house I'm going to try and understand just how this system works and figure out what kind of problem I've created.
I drove it around town today for the first time (I drive highways... live in the middle of nowhere) and it's popped 2195/2197 lean codes a couple times... so vacuum leak it is.
I haven't looked into it too hard but I'm thinking that my valve is not air tight (which is critical for the mod to work). I ran a quick line from the lower port of the valve back to the intake (stock) to temporarily fix it but that sort of defeats the purpose of the mod a bit.
At boost it'll still close the valve which is fine. But at low load, vacuum is applied at both ends of the err... plunger/piston and I'm not even sure if it'll open the valve or not because of that - especially when there's a spring always asserting a small force to keep the valve closed.
It was dark by the time I did this so I'll have to look again tomorrow to see if it opens the valve at all now that I added a line back to the intake. But honestly I'm thinking that my valve is worn and not air tight at all if this has worked for everyone else.
I haven't looked into it too hard but I'm thinking that my valve is not air tight (which is critical for the mod to work). I ran a quick line from the lower port of the valve back to the intake (stock) to temporarily fix it but that sort of defeats the purpose of the mod a bit.
At boost it'll still close the valve which is fine. But at low load, vacuum is applied at both ends of the err... plunger/piston and I'm not even sure if it'll open the valve or not because of that - especially when there's a spring always asserting a small force to keep the valve closed.
It was dark by the time I did this so I'll have to look again tomorrow to see if it opens the valve at all now that I added a line back to the intake. But honestly I'm thinking that my valve is worn and not air tight at all if this has worked for everyone else.
Why don't you just plug it.
While the area and between the two side of the plunger isn't air tight - the actual container is so I doubt the plunger would move it all. Unless I'm missing something?
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