system too lean bank one and bank two

[98spedition]

no matter what i do to try and fix the system too lean on both banks, it keeps coming back. the truck is a 98 with the 4.6L. If I clear the codes they will only come back once I drive the vehicle and put the engine under a load. please help!?! I am at a loss.

 

[lakmflx]

What codes are you getting? that would help...

 

[green03]

check for a broken vacuum line (or any vacuum leak) or air leak between the throttle body and mass air meter....

 

[MaverikDS]

I too am getting the codes saying that bank one and bank two are running lean. I first got it several months ago and had a friend clear it out. It did not occur again until just the other day. Again, friend cleared it out but this time it was only for one of the banks. The code was P0174. I believe it happened when the engine was about 168 degrees (warming up) when my roommate was driving to work. We cleared the code from the other day and then yesterday (three days inbetween) it went off again. I dont have any hoses that are broken and don't kwow what it could be. I did have new exhaust and headers put on if that is a factor otherwise the car is stock. Any help would be much appreciated.

 

[tonydiv]

Things to check out.

Dirty mass air sensor

O2 sensors bad

exhaust system leak

intake leak (between mass air and throttle body)

Vacuum leak (although this will usually throw its own code)

 

[RedRanger91XLT]

P0174 Ford Fuel System Too Lean (Cylinder Bank 2)

 

[JUST4FUN]

both banks lean. unmeterd air is getting into the system
vaccume leaks are top also check the PCV SYSTEM
including the plastic hose