exhaust valve wont open with jb4

[sams2k]

hello
i need your help friends
i have a 2021 supra 3.0 gr, i have been using jb4 for almost a month now with zero problems on map 2
today i code the car to open the sport + function and went out for a nice back road drive
from the start i notice a very weird sound from my exhaust
after i did some checking i saw that my exhaust valve is not opening, not in ideal and not under WOT, and it dosnt metter which driving mode i use.
the car sound choked under WOT.
i unplug the jb4 from the obd port, restart the car and everything went back to normal.
i try a few times to shut down and start the car, i even try to do all the codding process again
the problem is still there.
the only way to drive the car in WOT is with the jb4 unpluged.
anyone know this problem? any solution?

Sponsored

 

[BadOne]

From what I've read, I believe you have to tell it to open/close the exhaust valve.
Thread below:

https://www.supramkv.com/threads/exhaust-flap-closes-jb4.6933/

Not sure if that's what is going on, but that's all I could find for you.

It's issues like this that make me glad I went with the AWE exhaust.
No flap issues to worry about anymore.

 

[sams2k]

From what I've read, I believe you have to tell it to open/close the exhaust valve.
Thread below:

https://www.supramkv.com/threads/exhaust-flap-closes-jb4.6933/

Not sure if that's what is going on, but that's all I could find for you.

It's issues like this that make me glad I went with the AWE exhaust.
No flap issues to worry about anymore.

thank you for the fast replay, i actually like the exhaust valve and like to control the sound volume.
this post sounds very similar to my problem, but thats weird because everything worked amazing until today and the coding i did.
i never had to manually open or close the valve i didnt even knew its possible

 

[Benjilis]

Press the BC button on the left stick. Hold it down and use right turn signal. You should see the turn signal flash once on your dash.
you can tell it worked by the tone or checking yourself.
May take a few attempts.

 

[Stann_13]

Currently have this issue as well. Also recently installed jb4 for a month now, I noticed my valve won't open when I press sport mode. I tried waiting for a few minutes for the engine to warm but still won't open. So I just used the BC button to open the valve. I thought the issue was with my exhaust and thinking of bringing it to a shop to get it check. It would be nice to have the OEM setting back for the valve.

 

[sams2k]

Currently have this issue as well. Also recently installed jb4 for a month now, I noticed my valve won't open when I press sport mode. I tried waiting for a few minutes for the engine to warm but still won't open. So I just used the BC button to open the valve. I thought the issue was with my exhaust and thinking of bringing it to a shop to get it check. It would be nice to have the OEM setting back for the valve.

i saved you a trip to the shop the problem is 100% in the JB4
i guess i can use the BC button as a temporary fix but thats really not a solution
you need to use the BC button every time you start the car ?
its so weird, everything worked great for me and suddenly stoped working
i hope the guys at JB4 will solve it soon
i will try to mail them

 

[Supra_Gus]

hold the BC button on the turn signal.

Left flash = open valve
Right flash = closed valve
Both flash= normal operation (closed valve on comfort, open valve on sport)

 

[underdonk]

Why would this have suddenly stopped working for folks without any external change? Assuming people haven't updated anything that would have suddenly made it stop working...

 

[AHP]

Mine defaulted to always closed when I did a firmware update (v22). I'm assuming it's a bug; if they're now shipping with that version then it will probably be an issue out of the box. It threw me for a loop when logging since it caused my already high trims (high E content) to completely max out. The above steps for the BC button is the way.

 

[sams2k]

Mine defaulted to always closed when I did a firmware update (v22). I'm assuming it's a bug; if they're now shipping with that version then it will probably be an issue out of the box. It threw me for a loop when logging since it caused my already high trims (high E content) to completely max out. The above steps for the BC button is the way.

im sorry, i forgot to say but i also did the update to v22 3-4 days ago
yesterday with all my checking i went back to v20 but the problem didnt solve

 

[sams2k]

hold the BC button on the turn signal.

Left flash = open valve
Right flash = closed valve
Both flash= normal operation (closed valve on comfort, open valve on sport)

just to make it clear -
i start the car, let it worm up
i press the BC button and hold it, then i turn the lever up or down according to what i want? open or close?
and how i get both flash?

 

[Evolution]

just to make it clear -
i start the car, let it worm up
i press the BC button and hold it, then i turn the lever up or down according to what i want? open or close?
and how i get both flash?

No just press and hold the bc button. The blinker lights on the dash will flash after a couple seconds telling you what mode it's in.

 

[sams2k]

No just press and hold the bc button. The blinker lights on the dash will flash after a couple seconds telling you what mode it's in.

ohhhh ok
i do it every time i want to reset my trip odometer
i never knew about thos function
maybe i caused the problem?? ?

 

[underdonk]

Ahhhh, so it was a firmware update. Makes sense!

EDIT: Hopefully they get this fixed in v23. Assuming it's been reported.

 

[sams2k]

ok, a quick update
i also sent an email to BMS about this problem
they say -

"Try changing the JB4 canflap setting by adding "canflap" as a gauge in the app and double-clicking it, to see what happens."

i did and it works, the same idea as using the BC button.
but the valve still dont work with the sport button(right and left blinker flash together), i report back to them and waiting for an answer.
but at least i can drive the car now with the JB4 connected.
i will update you when i have news.
thanks everyone.

Sponsored