Trouble Codes

MarkD · February 19, 2009

2 codes that said

lean condition bank 1

lean condition bank 2

I have run aerosol Seafoam through the intake and vacuum line from brake booster.

I have also used a CRC brand MAF cleaner.

I will be changing the fuel filter tomorrow.

Any ideas?

dlstewart01 · February 19, 2009

P171 & P174. Usually an air leak in the intake system. Either between the MAF and the throttle body, or an intake gasket leak.

Don

D&SYukonDenali · February 19, 2009

Or the MAF sensor itself. How many miles?

MarkD · February 20, 2009

P171 & P174. Usually an air leak in the intake system. Either between the MAF and the throttle body, or an intake gasket leak.

Don

Thats what I am thinking. This happened just after replacing the knock sensors. I made every effort to get a good seal on the intake though.

Any ideas on finding an air leak other than taking it back apart and putting it back together?

MarkD · February 20, 2009

Anyone?

Draenor · February 20, 2009

Spray some WD40 or cleaner around the intake. You will probably hear a change in RPM when you hit the spot.

dorman68 · February 20, 2009

Possible intake manifold gasket. I have seen a couple of these.

D&SYukonDenali · February 20, 2009

Anyone?

On my non-truck vehicle, I dropped my work light into the engine bay, turned off the lights in the garage, and took an inspection mirror into the intake tubing (took off the MAF and started at that end). What I looked for was light inside the intake tubing. Light reflecting off the mirror would indicate a crack.

However, I did not have a crack in the intake. It was the MAF sensor when it was all said and done.

Also, there is also a smoke test that can be done.

MarkD · February 21, 2009

Well, this morning, I:

1. Changed the Fuel Filter

2. Changed the rear diff fluid (i know, but since I was working on the truck...)

3. Removed MAF and cleaned with CRC Product

4. Removed TB and cleaned/reinstalled

5. Found drivers side rear intake bolt not as tight as others, so I checked all

6. Checked all fasteners and connections (all ok)

7. I will reset the DTC light tomorrow and see if it comes up again. If it does, I guess i will try the WD-40 test and remove the intake.

Thanks guys! Any other help is appreciated.

MarkD · February 21, 2009

bump

superjim · February 21, 2009

bump

Did the code come back after re-setting it?

From what I have read...it almost has to be a leak in the intake system of a bad MAF.

BrakeKleen spray will work for spraying around the intake and won't leave the greasy residue that attracts dust like WD-40 and as an added bonus, it cleans whatever you spray it on.

MarkD · February 21, 2009

It will be monday before I can get them reset (weekend daycare duty). I'll check again monday.

D&SYukonDenali · February 21, 2009

Did you look at that link I PM'ed you?

MarkD · February 21, 2009

Yes.

MarkD · February 22, 2009

I gathered several things from the BMW forum.

1. These guys know how to throw money at a problem!

2. One guy replaced his MAF

3. One guy is replacing his fuel injectors

4. One guy replaced all of the flexible rubber parts on his intake

I am hoping that the loose intake bolt will solve my problem. I drove the truck about 30 miles before the SES light came on. After I cleaned the MAF and tightened the intake, it seems to idle better. Off idle runs good.

I have also added Seafoam to fuel and vacuum lines and replaced the air filter (it needed it).