Cobb GR Stumble Fix Fuel Pressure Regulator

[@11Xshadowolf]

As short as this video is, it has so much great information for this install . I am grateful for you making this video and your attention to the little details and no bs. deff going to sub to you keep it up !

[@ModdingAddiction]

That's the whole reason I even have a channel. Thank you so much that means a lot and keeps me motivated.

[@BushidoPhoto]

This was super helpful, thank you!

[@gubbilo1]

Great installation video,just installed mine 👍

[@ModdingAddiction]

How did it go?

[@opticsmedia.official]

Just what I needed.

[@AlizingEstigoy]

thanks for showing this video bro👍🏼its a big help😊

[@ModdingAddiction]

You got it my dude 👍 thanks for the comment

[@franny1179]

Thank you for the video amazing explanation, do I have to take the car for tune after install the cobb fuel pressure

[@ModdingAddiction]

Yes and no. You don’t have to but it’s not going to fix the problem till it gets tuned out. They can push it further up the rev range so you don’t notice it when your driving

[@Eegoor1976]

After I installed this and 1050x injectors I can’t build boost. I blocked off that old vacuum line and installed the T in the BPV like the directions said to. I’m scheduled for a tune. Oh and I’m not throwing codes either. I noticed my AF learning 1 doesn’t show up on my AP either

[@ModdingAddiction]

I believe there is a small 1/4 nipple on the riverside of the intake plenum that need blocked. The old fuel uses it as a reference. I vaguely remember having to fabricate a cap for it. If it’s not that sound like a vacuum leak after the turbo

[@michaelnasrallah]

If you upgrade to e85 system, do you still need the stumble fix, or does the e85 kit basically do the same thing?

[@Ruffles206]

Need tuning? Nice video

[@ModdingAddiction]

Thanks for the comment. As far as needing a tune yes you do. There is I think a 20% increase in the fueling tables that needs to be corrected for. Not sure how accurate that that number is but I vaguely remember reading that somewhere. It is a good supporting mod to do before you go for a tune though. Fairly cheap, really easy and helps the car out a ton with the stumble.

[@rogerucles8830]

How long did you go without a tune after installation?

[@BushidoPhoto]

Did you have to get a custom tune to install this stumble fix? Thanks again.

[@ModdingAddiction]

It is best to get a tune for it as it is changing the fuel delivery system

[@JDMreck]

what about if i wanna use bigger injetors will this work too thinking in going full e85

[@troshaffer4921]

I know this is old, but would anyone know if this would work on a h6? Or does anyone know of a good adjustable fpr for it? I'm having problems with my fpr & they don't make the denso replacement. Wanna get an adjustable one but no one knows anything lol

[@stephenmargetjak6989]

Hello, did you do a tune after the reg install?

[@mrhasnohand]

What were your results from this. Did it get rid of the stumble

[@miggy2225]

Same thing for 16' STI correct? Also great video !!

[@ModdingAddiction]

Yeah it seems to be a known issue but subaru hasn’t corrected the problem yet. A cobb fpr kit and a tune and you will be dialed

[@takeda1648]

Video is helpful, i watched this video about 10 times cause i have a flex fuel kit lmao, thank you for this video

[@ModdingAddiction]

I’m glad that it was helpful. Hopefully everything went smooth with the install

[@jonathanramirez548]

Did you still need to use it ? When you have the flex kit

[@whocares5188]

My 2015 sti will randomly stumble like you said but it will also die. It will start right back up and be fine. Do you think I need the stumble kit

[@TheZimmyHD]

If it shuts off sounds more like fuel pump

[@whocares5188]

@@TheZimmyHD I replaced the fuel pump. I'm thinking cam sensor. Now when it dies I have to pump the gas to keep it going for like 3 mins then it comes back to normal but it's dying alot now. I haven't been driving it much but I'm ready to figure out the problem. One thing I noticed is my horn don't work most the time but sometimes it does. I'm hoping it's not electrical

[@SteveLyons57]

after the install, would it be safe to drive to the tuner?

[@neryurrutia2145]

Did anyone know why i got the cobb1 and cobb3 engine light after i install the flex fuel kit and FPR? It said fuel sensor low input voltage

[@ModdingAddiction]

Have you had the car tuned after installing?

[@OscarLopez-gq4he]

cobb light ? wtf

[@diegosti9741]

do you need a tune for that?

[@哈哈哈-e4i]

May I know the JDM GRB also will have the stumble issue?

[@thetoffinator]

Yes, same system

[@M0nST3R691]

What happens if u have a front mount instead or a top mount

[@ModdingAddiction]

The gr stumbled is most noticeable on a stage two off the shelf map. If you have a front mount chances are you have a pro tune. If you went to someone that does Subaru’s often then chances are they tuned it out for you. Most likely they just pushed it up the rpm range. Do you have a bigger fuel pump? This would help get rid of it. That being said if you have it you know you have it. The car will surge like it’s hitting a fuel cut

[@hanksch]

So did this resolve your GR stumble as advertised?

[@ModdingAddiction]

That is a loaded question lol. Short answer yes but no. Long answer it shifts the harmonic rhythm of the two fuel lines higher in the RPMS. So at lower cruising speeds it does help around 2800-3000 where is is noticeable but moves it to 3300-3500 RPM where you aren’t cruising. That being said it isn’t as noticeable but still there. Hopefully that helps. If you have any other questions I would be happy to help

[@hanksch]

Great video by the way. I have read recently the same thing about the resonance you mention. I wonder if the resonance is actually removed because the fuel is being circulated thru the rail. The OEM configuration is not circulated thru the rail, but bypassed to the return line, thus allowing bigger impact of the injectors pulsing, creating resonance. I don't have the tools to test my theory. Thanks for the response, very appreciated.

[@leandropim]

@@hanksch should the fuel damper on the feed line improve this?

[@hanksch]

@@leandropim in addition to this mod, I installed an aftermarket damper, that helped a little. Then I ended up replacing all the fuel rails with braided parallel AN lines. That seemed to fix it. Big pain in the neck.

[@nguyen1314]

Any advice or different after the installed ?

[@ModdingAddiction]

Defiantly a noticeable difference. But it is still a little noticeable. This just shifts the stumble up the rpms. You don’t notice it really unless you cruise at 80-85 mph

[@MIL1120]

@@ModdingAddiction so this is just for stumble? I'm gonna run e85 but I was trying to verify if this is needed , I came to the conclusion it doesnt

[@Dorganzola]

Yes it is just for the stumble but it will work for replacing these two lines to make them e85 capable. However I found this out after I bought mine is that an e85 or flex fuel kit comes with these hoses. More often then not. Hope that helps

[@MIL1120]

@@Dorganzola I get ya . Yea I'm getting the Cobb flex fuel kit. Idk if I'm doing the install myself or paying someone to do injectors pump and flex fuel kit

[@nguyen1314]

Hi joe

[@ModdingAddiction]

Yo joe

[@jllindle]

Didn't fix shit for me.