[Vladkurk]

Hello forum, I have a 2007 335i e90 and I’ve got this dreaded p2096 code I cannot figure out. It is a Post catalyst fuel trim system too lean bank 1 code. I need to pass emissions but this code won’t let me. I had some 02 code pop pout with it but since changing bank 1 sensor 1, the code has went away. Any help? I will post pics of live data and code on my scanner.

Also, I put in catless DPs and MHd flash. Have had no issues for over a year with the setup with no codes. Thanks guys.

[Bali]

Post the freeze frame data and warm idle long term fuel trims for starters.

Personally, I’d dump that scanner and get the OBD Fusion app and a wireless OBD adapter for less than $40 for both. It will run circles around an Actron.

[Vladkurk]

Originally Posted by BaliDawg

Post the freeze frame data and warm idle long term fuel trims for starters.

Personally, I’d dump that scanner and get the OBD Fusion app and a wireless OBD adapter for less than $40 for both. It will run circles around an Actron.

I should sooner or later but as of right now I can’t get freeze data. I will as soon as I can. I’m just wondering if anyone has ran into this code and see what they did to fix

[mweisdorfer]

Originally Posted by Vladkurk

I should sooner or later but as of right now I can't get freeze data. I will as soon as I can. I'm just wondering if anyone has ran into this code and see what they did to fix

You need a dedicated scan tool that is BMW specific. Foxwell/ Schwaben scan tool. This will give you specific bmw codes.

P2096 = too much air, not enough fuel. Basically, you are running too lean.

Check for leaks in your intake.

[Vladkurk]

Originally Posted by mweisdorfer

You need a dedicated scan tool that is BMW specific. Foxwell/ Schwaben scan tool. This will give you specific bmw codes.

P2096 = too much air, not enough fuel. Basically, you are running too lean.

Check for leaks in your intake.

Is there any common areas that the n54 leaks at? I’ve changed the 2 front vaccuum hoses on the valve cover. I tried the starting fluid trick but couldn’t find any more leaks :/

[mweisdorfer]

Originally Posted by Vladkurk

Is there any common areas that the n54 leaks at? I’ve changed the 2 front vaccuum hoses on the valve cover. I tried the starting fluid trick but couldn’t find any more leaks :/

Why not change out all the vacuum lines? Get about 15-20' of platinum cured lines from Verocious Motorsports. Look up the diy on how to use a piece of copper wire to do the front turbo.

You need 3.5mm

https://www.verociousmotorsports.com...ld-by-the-Foot

However, check/ change your gaskets at connection points like the FMIC, charge pipe to the throttle body etc. Make sure your inlets on both turbos are in. The oem connections are rather weak flimsy. You'll have to take off at least one down pipe to get to the rear turbo.

Make sure your lower charge pipe is secure to the upper charge pipe.

[Vladkurk]

Originally Posted by mweisdorfer

Why not change out all the vacuum lines? Get about 15-20' of platinum cured lines from Verocious Motorsports. Look up the diy on how to use a piece of copper wire to do the front turbo.

You need 3.5mm

https://www.verociousmotorsports.com...ld-by-the-Foot

However, check/ change your gaskets at connection points like the FMIC, charge pipe to the throttle body etc. Make sure your inlets on both turbos are in. The oem connections are rather weak flimsy. You'll have to take off at least one down pipe to get to the rear turbo.

Make sure your lower charge pipe is secure to the upper charge pipe.

I’ve changed the 2 lines on top of the valve cover that go to the canisters and the ones that are for diverter valves. Any other vaccum lines I’m not aware of. Every diy just shows the ones I’ve replaced already

[Vladkurk]

Originally Posted by BaliDawg

Post the freeze frame data and warm idle long term fuel trims for starters.

Personally, I’d dump that scanner and get the OBD Fusion app and a wireless OBD adapter for less than $40 for both. It will run circles around an Actron.

I cannot do freeze frame data unfortunately on my scanner

[mweisdorfer]

Originally Posted by Vladkurk

I’ve changed the 2 lines on top of the valve cover that go to the canisters and the ones that are for diverter valves. Any other vaccum lines I’m not aware of. Every diy just shows the ones I’ve replaced already

Did you get the lines going directly to each turbo?

[mweisdorfer]

Originally Posted by Vladkurk

I’ve changed the 2 lines on top of the valve cover that go to the canisters and the ones that are for diverter valves. Any other vaccum lines I’m not aware of. Every diy just shows the ones I’ve replaced already

Pics

[Vladkurk]

Originally Posted by mweisdorfer

Pics

Yes I’ve changed those too. I just forgot about them and didn’t mention it

[mweisdorfer]

Originally Posted by Vladkurk

Yes I've changed those too. I just forgot about them and didn't mention it

Ok, so I'd just start going through your connection points. You might want to order up some turbo seals & gaskets that seal the exhaust to the cats. Your are going to want to check the inlet connection to the rear turbo. You have to take at least one cat out to do that.

From my experience, the OEM inlet connections are not really on there all that well.

[Vladkurk]

Originally Posted by mweisdorfer

Ok, so I'd just start going through your connection points. You might want to order up some turbo seals & gaskets that seal the exhaust to the cats. Your are going to want to check the inlet connection to the rear turbo. You have to take at least one cat out to do that.

From my experience, the OEM inlet connections are not really on there all that well.

Down pipes and exhaust gaskets are new. I’ll check turbo side but I think it doesn’t matter because it doesn’t meter the air before the intake. If it’s some sort of vaccum leak then it must be something after the intake not before it if that makes sense.

[mweisdorfer]

Originally Posted by Vladkurk

Down pipes and exhaust gaskets are new. I’ll check turbo side but I think it doesn’t matter because it doesn’t meter the air before the intake. If it’s some sort of vaccum leak then it must be something after the intake not before it if that makes sense.

Turbo seals are only good for so long. I'd say after 125-50,000 miles they need to be replaced for sure.

If you pull the down pipe out, you could dip the gasket(s). I did and they were just put on in April.

Check you FMIC rubber gaskets. Those are notorious for going bad after 100,000 miles.

[Vladkurk]

Originally Posted by mweisdorfer

Turbo seals are only good for so long. I'd say after 125-50,000 miles they need to be replaced for sure.

If you pull the down pipe out, you could dip the gasket(s). I did and they were just put on in April.

Check you FMIC rubber gaskets. Those are notorious for going bad after 100,000 miles.

I’ve checked them they are good. It wouldn’t matter anyways. I wouldn’t get a lean code for broken boots on the intercooler. I’m getting unmetered air/too much air not boost leak. It doesn’t meter the air circulating before it hits the intake manifold.


Anyone on this forum come across this code specifically?

[Vladkurk]

Just an Update,

For so much headache and so much freaking wasted time and no complete forum post I could find on this issue, I’ve finally solved it. Countless hours of researching with just dead ends online and in shops.
This car has been to 2 seperate Indy Bmw shops with no results but 250 dollars wasted on diagnostics. I’ve had hand full of Bmw inclined people take a look with everyone stumped.
With my research, this P0296 code can mean a few of things.

- You have a vacuum leak somewhere, either it be vacuum lines running across the valve cover or intake gaskets

- Your injector/injectors are leaking or fuel pump are giving out and not enough fuel.

- Your downstream 02s are plugged in wrong or they have failed.

- You have a exhaust leak around your down pipes



I’ve diagnosed everything and I still didn’t fix the problem. I changed all my vacuum lines, did a smoke test afterwards, still code was there.

I tested my fuel pressure in the rail And ruled out the HPFP pump going out. Personally I ruled out the injectors going out because the car idled good and I wasn’t losing power either.

I have installed vrsf catless downpipes about 6 months before this code popped up but still I checked if my wiring got fried down there just in case, I checked for leaked and everything was fine.
To check the 02 sensors, I checked the voltage of both the downstream sensors with my code reader using live data and they showed they were good but I still changed them just cause I was stumped and couldn’t conclude anything else being wrong.
I changed them and code stayed there.

So, the car being thru 2 mechanics and few people after me messing with it, I was stumped at what was causing this code. Long story short I was browsing thru some forum about MHD tuning because I installed catless dps and have a MHd tune and I was just reading up on something unrelated when I read a post about people’s Air fuel ratios being out of wack after a while for some reason with their MHD tunes. I don’t remember what or why but I’ve tried tracking down the forum so I can link it here but someone had a AFR issue and thru the MHD flash app they reset Adaptations for 02 sensors and they solved whatever issue they had. So I said what the heck and plugged in my obd2 cord and launched the App and reset adaptations for 02s and viola, code never popped up again and I was able to pass emissions finally. I believe I could of just done that first and avoided everything I’ve done. Someone educated with mhd should correct me on this but seems like with a MHD flash your AFR get skewed after a awhile from what I understand and I assume that’s what causes my code to pop up and not go away no matter what I changed.


So for whoever has this issue and can’t figure it out, try what I did. I just figured I’d post my results and who knows I’ll help someone in the future. This probably the most annoying code I’ve ever delt with. Lol

[lukestimpop]

I just purchased the FIXD OBD scanner that connects to your phone and I too came across this code (P2096). This thread is very helpful thank you for posting a final update. I'm going to try to self diagnose this issue and see if I can find the problem by myself, wish me luck.

[mikejones9547]

hello all i am having a few codes thrown on my 08 335i p2196 p2096 p1447 and p0303 hoping someone has some experience with this combination or codes car has a service engine light that comes and goes but mostly stays and goes into reduced engine output here and there but after i stop and restart the car back to just the service engine light