[halcyon026]

I'm getting the code "P0171 too lean bank 1".

Here's a list of the last few things I've done.

I cleaned my DCI's 2 days before getting the code.

I also tried to run 100% meth 2 days ago but it seemed to be evaporating in the lines so I went back to 50/50 (hazards would turn off and Service Engine soon would flash 5 times).

Installed Kitty-less DP's 2 weeks ago.

Those are the only things I've touched on the car recently.

It happens when I'm just cruising at 1300-1500 RPM's.

I run 3.0-3.2 gallons of E85 with Chevron 91. Been doing so for a year.

What possible causes could this be and could you point me to how to troubleshoot each item?

Here's my mods

PROcede v5 | DME reflash | Vishnu Meth Kit | DCI | Helix FMIC | BMS OCC | RB PCV valve | Alpina Flash | VRSF catless DP's | Scoops

Thanks a ton for any help!

[DetectiveLoki]

I get this code from time to time when I don't let my car idle for a little bit after turning it on. Performance doesn't seem to be affected. I just clear them with my OBD2 reader. I'm also curious why I get this code as well.

[grussauto]

I would stop using E85 immediately and run 100% 91 octane. E85 does not burn as efficiently as 91 octane gasoline and is very hard on fuel components and causes carbon build up much quicker than gasoline. The E85 could be messing with your )2 sensors. BMW even states in the owners manual to not use E85. Run your tank down to as close to empty as possible and then fill up with 91 octane and put in some fuel system cleaner and see what happens. You will also find that with the 91 octane you will get better mpg than E85 and your engine will run cleaner.

[Miller335]

Originally Posted by grussauto

I would stop using E85 immediately and run 100% 91 octane. E85 does not burn as efficiently as 91 octane gasoline and is very hard on fuel components and causes carbon build up much quicker than gasoline. The E85 could be messing with your )2 sensors. BMW even states in the owners manual to not use E85. Run your tank down to as close to empty as possible and then fill up with 91 octane and put in some fuel system cleaner and see what happens. You will also find that with the 91 octane you will get better mpg than E85 and your engine will run cleaner.

Lol wut?

[teamraw]

Just got this code on my 335is last night did you find out what the problem was ? Please help