[MachWon]

Is this happening to anyone else? Before the update, my car never backfired on shifts and rarely ever backfired while hit 2-Step. After updating my JB4, the car is backfiring about 70% on 1-2 shifts above ~6000 RPMs. Sounds like an M80 is going off in my exhaust. I'm also spitting flames when this happens. Haven't tried the 2-Step after updating.

Also, the update did not help my wastegate rattle any more than previous software versions.

[335NJ]

Did you set FUD to 98?

[MachWon]

Yes sir. Also getting 30FF and 3100 codes now in both normal driving and long pulls.

I set whatever option was supposed to be 0, to 0, so I don't think that's the problem as far as the underboost codes go.

[brewnami]

My car has been undrivable for 5 weeks so far after updating the newest firmware...

[335NJ]

Have you set all the DUTY BIAS values to 0? All of them?

Do you use a backend flash?

[MachWon]

Duty Bias is set to 0. No backend flash as I don't have a BT cable (one is in the mail ��)

[335NJ]

Originally Posted by MachWon

Duty Bias is set to 0. No backend flash as I don't have a BT cable (one is in the mail ��)

You've basically just copied everything from the N54Tech "JB4 firmware" section, in the user settings correct?

Make sure you don't have gears 1-2-3 set to some weird boost value, and make sure you're JB4 is set to 4/3 since you don't have a backend flash yet.

Post a screenshot of your interface settings.

[MachWon]

Bumping this because the issue never went away.

I can now shoot flames at people pretty much on command. The car is after firing when I shift near redline, on 1-2, 2-3, and sometimes 3-4. I can also do it in second sometimes by spooling up the turbos and then cutting the throttle (3-4k rpms)

I don't know what to think. The car isn't running super rich, I believe the afr's were in the 12s last time I looked. It just shoots flames and sounds like gunshots.

[Jaronbwall]

Originally Posted by MachWon

Bumping this because the issue never went away.

I can now shoot flames at people pretty much on command. The car is after firing when I shift near redline, on 1-2, 2-3, and sometimes 3-4. I can also do it in second sometimes by spooling up the turbos and then cutting the throttle (3-4k rpms)

I don't know what to think. The car isn't running super rich, I believe the afr's were in the 12s last time I looked. It just shoots flames and sounds like gunshots.

And this is a problem why??

[Rat_House]

did you add any new mods at the same time and not reset adaptations? When i install a 7inch I/C the same thing happened to me for a week or so until the DME adapted

[fulltilt444]

Have you reached out to BMS...? That would have been my first, second, and third move. good luck!

[MachWon]

No new mods. I just updated the firmware on the JB4. I have since updated again and it still does it, so I'm thinking it may be a hardware issue not related to the tune.

I don't mind it, but I don't want my car to blow up because of it.

[335NJ]

I'm wondering if one of the O2 sensors are faulty? It's doubtful though. Is it doing it on both sides of the exhaust or just one? Either way, that's not normal, and something somewhere is causing unburnt fuel to make its way down the exhaust.

[MachWon]

Both sides, and my exhaust flapper is unplugged. Could carbon buildup be the cause, or bad plugs? I just recently got a stumble on idle and light throttle, so I'd say it's time for new plugs either way.

Edit: I'm also fully catless.

[335NJ]

I'd definitely start there. Get fresh plugs in, and a walnut blast. Make sure the throttle body isn't all caked up too.

Then I'd try to use INPA and make sure the injectors look OK.

[TheYuriPanda]

Wish i could shoot at all of these tailgating ..... here in Denver.

[MachWon]

Update: got a 29e0 code today. I believe I got that + a 29e1 yesterday, but I accidentally cleared those codes.

Seems like it might be an 02 as 335NJ said, or possibly leaky injector? I get a odd bubbling noise from the rear of the valve cover right after I turn off the car. Have to have the engine cover off to hear it.

[v1nc86]

Get a log and post it in the N54Tech support section ! Nothing better than a log...