P0175 Code - Bank 2 Rich

[cebra]

I have a 00' 4.8L in my truck (can't recall engine code) that I have drove about 25K miles on now. About 1K miles ago, it threw a P0175 code and I started trying to resolve this without success thus far. Any ideas on things to replace to try to resolve this? I cleaned the MAF, replaced MAF with another junkyard variant, ran injector cleaner through it and no luck. The 02 sensors were new 25K miles ago but they are cheaper models. The truck has always appeared to run a little rich but I drive it at about 750 miles a week and it runs pretty good, maybe slightly down on power.

[mongocanfly]

Might try swapping the o2 sensors side2side...or just replace them..
But this may not have anything to do with your issues...just a guess

[AussieinNC]

Apologies in advance for the long winded response...but here it goes...

A code P0175 may mean that one or more of the following has happened:

The MAF (Mass Air Flow) Sensor is dirty or faulty.
Note: The use of "oiled" air filters can cause the MAF to become dirty if the filter is over-oiled
There could be a vacuum leak.
There could be a fuel pressure or delivery problem Possible Solutions
Possible solutions include:
Inspect all vacuum and PCV hoses, replace if necessary
Clean the MAF sensor.
I find it's best to take it off and spray it with electronics cleaner or brake cleaner.
Make sure you are careful not to damage the MAF sensor, and make sure it's absolutely dry before reinstalling
Inspect fuel lines for cracks, leaks, or pinches
Check the fuel pressure at the fuel rail
Check the fuel injectors, they may be dirty.
Use fuel injector cleaner or get them professionally cleaned/replaced.
Check for an exhaust leak before the first oxygen sensor (this is unlikely to cause the problem, but it is possible)

Have you cleared the codes, removed the battery for ten minutes and then completed the relearn drive cycle process?

The trim fuel parameters may need to be relearned over several relearn processes...

Drive Cycle Process

A complete driving cycle should perform diagnostics on all systems.
A complete driving cycle can be done in under fifteen minutes.

To perform an OBDII Driving cycle do the following:

Cold Start.
In order to be classified as a cold start the engine coolant temperature must be below 50°C (122°F) and within 6°C (11°F) of the ambient air temperature at startup.
Do not leave the key on prior to the cold start or the heated oxygen sensor diagnostic may not run.
Idle. The engine must be run for two and a half minutes with the air conditioner on and rear defroster on.
The more electrical load you can apply the better. This will test the O2 heater, Passive Air, Purge "No Flow", Misfire and if closed loop is achieved, Fuel Trim.
Accelerate.
Turn off the air conditioner and all the other loads and apply half throttle until 88km/hr (55mph) is reached.
During this time the Misfire, Fuel Trim, and Purge Flow diagnostics will be performed.
Hold Steady Speed.
Hold a steady speed of 88km/hr (55mph) for 3 minutes.
During this time the O2 response, air Intrusive, EGR, Purge, Misfire, and Fuel Trim diagnostics will be performed.
Decelerate.
Let off the accelerator pedal. Do not shift, touch the brake or clutch.
It is important to let the vehicle coast along gradually slowing down to 32km/hr (20 mph).
During this time the EGR, Purge and Fuel Trim diagnostics will be performed.
Accelerate.
Accelerate at 3/4 throttle until 88-96 km/hr (55-60mph). This will perform the same diagnostics as in step 3.
Hold Steady Speed.
Hold a steady speed of 88km/hr (55mph) for five minutes. During this time, in addition to the diagnostics performed in step 4, the catalyst monitor diagnostics will be performed. If the catalyst is marginal or the battery has been disconnected, it may take 5 complete driving cycles to determine the state of the catalyst.
Decelerate.
This will perform the same diagnostics as in step 5. Again, don't press the clutch or brakes or shift gears.

[truckdude239]

I doubt it is a masd flow issuse since it is only setting one side u can get Denson brand o2w senzors on Amazon for like 40 buxs more then likely u have an injector hanging up for a rich code on one side