A co-worker keeps throwing codes for lean bank 1 and 2 when it's cold out. Truck will run fine all summer but as soon as it's cold out the codes show up.

Could it be a dirty MAF sensor or possible leak on the intake tube?

I'm going to try to clean the Maf with some brake cleaner but have never done it before. Just spray it real good and let it dry right?

 

I don't know if it matters or not Josh but they have a maf cleaner instead of the brake cleaner. Dries pretty fast

 

I think I already have some brake cleaner but If I don't I"ll check into that.

 

If it has high mileage, I would check the intake gaskets. That sounds like a possible small gasket leak.

 

I'm hoping not. Would an intake gasket leak ONLY when cold tho?
It has less miles than mine and not driven remotely as hard as mine. Female driver with 2 kids.

 

it can... my gaskets had to be replaced <85k and only had problems in the cold weather. cost me around 180 to get it fixed.

 

Thanks for the advice. I'll try to clean the maf. If that doesn't work I'll grab some carb cleaner and show her husband what to do.

 

I have had the same problem. I would go ahead and get the MAF cleaner, it is not as harsh on the sensor. Mine is giving me all kinds of problems, here is a link to my thread that I started awhile back. It is still giving me problems and I can't figure it out.

https://www.performancetrucks.net/fo...d.php?t=440419

 

If you think about it, materials shrink in cold weather, so it would open clearances and gaps. Thus causing an unnoticeable leak, to be noticeable.