[anaveragebmwowner]

Well lads after lurking for years I’m finally making an account and just asking a damn question. 29E1, 2A2C, replaced bank 2 o2 sensor and no change. One would think injectors however no consistent misfire and codes are very intermittent. Recently more regular and I’m getting 2C40 which is new, though seems relevant, check wires, they’re plugged correctly and can’t see any pinches or places where insulation is rubbed through. I’m stumped and I need help, thoughts?

[Bimmer_Bro]

Originally Posted by anaveragebmwowner

Well lads after lurking for years I’m finally making an account and just asking a damn question. 29E1, 2A2C, replaced bank 2 o2 sensor and no change. One would think injectors however no consistent misfire and codes are very intermittent. Recently more regular and I’m getting 2C40 which is new, though seems relevant, check wires, they’re plugged correctly and can’t see any pinches or places where insulation is rubbed through. I’m stumped and I need help, thoughts?

How does the car run and drive? Are you tuned? If so what version ?

All the 2c40 issues I have seen have been a wiring issue. Either damaged or pinched.

[anaveragebmwowner]

Originally Posted by Bimmer_Bro

How does the car run and drive? Are you tuned? If so what version ?

All the 2c40 issues I have seen have been a wiring issue. Either damaged or pinched.

Yep MHD and runs and drives just fine, slight rough idle on start up and then golden, I inspected the o2 wires and couldn’t see anything, worried it might be harness side. Any easy way to test for damaged wires?

[Bimmer_Bro]

Originally Posted by anaveragebmwowner

Yep MHD and runs and drives just fine, slight rough idle on start up and then golden, I inspected the o2 wires and couldn’t see anything, worried it might be harness side. Any easy way to test for damaged wires?

What map version of MHD tho? V10?v9?v7?

Slight rough idle on start or longer cranks can also be leaking injector.

Best way to test for this is let the car sit over night. Do not start the car . Pull out the spark plugs and see if any are wet with fuel. A leaking injector will cause the spark plug tip to be wet.

A leaking injector could also explain your mixture code for That bank.

[anaveragebmwowner]

Originally Posted by Bimmer_Bro

What map version of MHD tho? V10?v9?v7?

Slight rough idle on start or longer cranks can also be leaking injector.

Best way to test for this is let the car sit over night. Do not start the car . Pull out the spark plugs and see if any are wet with fuel. A leaking injector will cause the spark plug tip to be wet.

A leaking injector could also explain your mixture code for That bank.

I will test this, no crank problems though just a slight rough idle while cold and it clears up, I guess that is unrelated to the lean afr reading issue though? Also v10 maps, everything up to date there.

[Bimmer_Bro]

Originally Posted by anaveragebmwowner

I will test this, no crank problems though just a slight rough idle while cold and it clears up, I guess that is unrelated to the lean afr reading issue though? Also v10 maps, everything up to date there.

It’s most likely a injector or sensor issue (double check or maybe clean your maf sensor on the top back of the intake manifold).

I will mention that my car really does not like v10. I get bogus mixture codes when cruising (both banks).

V10 also requests max boost till redline which is pretty hard on the oem turbos. They run out of steam up top. The other maps taper down towards redline which keeps them a little happier and last longer.
My car runs great on v9 or v7 which is my favourite. Been back and forth between 9 & 7 for about 6 years.

[anaveragebmwowner]

Originally Posted by Bimmer_Bro

It’s most likely a injector or sensor issue (double check or maybe clean your maf sensor on the top back of the intake manifold).

I will mention that my car really does not like v10. I get bogus mixture codes when cruising (both banks).

V10 also requests max boost till redline which is pretty hard on the oem turbos. They run out of steam up top. The other maps taper down towards redline which keeps them a little happier and last longer.
My car runs great on v9 or v7 which is my favourite. Been back and forth between 9 & 7 for about 6 years.

Mate you’re a legend, I’ll flash to v9 today and see what happens, just a bit more context o2 is brand new, I’ve had these mixture codes for a year now on and off since flashing from stock to v10 so I’m super interested to see the difference.

[Bimmer_Bro]

Originally Posted by anaveragebmwowner

Mate you’re a legend, I’ll flash to v9 today and see what happens, just a bit more context o2 is brand new, I’ve had these mixture codes for a year now on and off since flashing from stock to v10 so I’m super interested to see the difference.

Let me know how it goes! It’s always good to rule out the tune before throwing more money and parts at it.

The reason I knew mine was tune related as it pretty much started a day or two after giving V10 a try. It would also trip both banks which is pretty rare if it’s hardware related.

If you still get the same code for the same bank I would maybe still think injector but try the tune first.

V9 has a liner boost curve which is nice for around town. However I still love v7 the best. My car idles smoother on it and the boost comes on like a kick in the back lol.

[anaveragebmwowner]

Originally Posted by Bimmer_Bro

Let me know how it goes! It’s always good to rule out the tune before throwing more money and parts at it.

The reason I knew mine was tune related as it pretty much started a day or two after giving V10 a try. It would also trip both banks which is pretty rare if it’s hardware related.

If you still get the same code for the same bank I would maybe still think injector but try the tune first.

Yeah I’ve been trying to rule out everything other than injector issue first 😂