I have a 2005 Accord coupe with a V6, and I have 2 trouble codes present:P0171 and P0174. P0171 is rear cylinder bank, fuel system too lean, and P0174 is front cylinder bank, fuel system too lean. Can somebody tell me what is the usual cause of these conditions? Thanks.

 

Could a dirty fuel filter cause the car to run lean?

 

Lack of fuel is one cause for a lean engine. Low fuel pressure, clogged injectors, clogged fuel filter, etc.. can cause this. You will have to do some diagnosis.

Is the car running poorly? Did you fill up the tank right before you got the codes?

 

The car is running fine, the check engine light turns on daily and is gone the next morning. Mind you, I drive the car for work everyday, sometimes for more than 7 hours a day. The CEL has been coming on and going off for several months now with no issues.

 

The first step in the troubleshooting is to check the fuel pressure...should be 55-63 psi at idle. There is no external fuel filter, it's part of the fuel pump module. How many miles on the car? Let us know what you find and then we'll continue on.

 

I have to get a fuel pressure gauge, I will post results this weekend, and hopefully the diagnosis will be less complicated!

 

I was told today by somebody that worked at a Honda service department that these codes may be caused by bad oxygen sensors