E320 fuel trim bank 1 and 2 troubleshooting
 

Hi, im a first time poster, but have viewed the forum for a few months now. I have a few questions pertaining to fuel trim, and one random but important question.

I took the maf hoses off to do my spark plugs and valve cover gasket on left, and after I assembled the maf hoses and such, After a few miles of driving I got this code: P0170 and P0173. Fuel trim banks one and two.
This ruining my fuel economy and I cant pass inspection. So I need a little help. I learned from this forum that it is maf related. So im gonna replace the whole hose, the gaskets and the maf sensor.

question 1:
When I put the gasket seals on (from throttle to elbow and hose to maf)
do I need to use gasket sealant?

question two:
I noticed that this hose is missing in the picture below. The hose is 140. What does it do and where can I get it?

Thanks for shedding an light on this subject. All facts and opinions are welcome, Especially for hose 140.

Question 1----No

Question two---do you think that #140 was missing before you started putzing around? Yes it is a dealer part used buy the emissions system---do not buy a MAF before replacing #140 and retesting and double checking your work!!

part 140 was missing before I replaced the maf. Like it was missing before I bought the car. I think it was causing an emission code (p0442). was it causing that code?

Who knows,but what happened to the fault if the hose was not attached--this is just going in circles, double check your work, make sure everything is attached and don't buy a MAF!!