I am having a problem with bank 1 being rich and bank 2 being lean. Codes are PO172 and P0174. I cant find any vacuum leaks, MAF is new, Air Filter is new, O2 sensors are new and pretty much all other sensors on motor except knock temp and crank sensors. Fuel filter has been replaced. Can this be a fuel delivery problem ranging from pump to regulator to fuel injectors. I have rough and no power on any incline of any kind. Instant power loss on Incline. Not for sure about milage as I was told motor was changed. Odometer says 277000. There are no knocks or pings in the motor. Longer the truck runs the worse it seems to get. Plugs wires and coilpacks also new. Any help at all would be apreciated.

 

Did this vehicle have this problem right from the time you bought it?

 

I got this problem after the front converter on the passenger side was replaced well both converters were replaced. The reason for replacing was the front converter started making a knocking noise, replaced converter and knock left. Dont know if any problems existed before that may have thrown codes, I guess the previous owner took the bulb out. I just happened to check and see if there were any codes and there was. Po174 will come first then Po172 noticed that when running truck today with scanner plugged in. Read codes after about 20min of running PO174 came up then about 10min after pulled the other code. Beats me

 

I'm not sure if this could be the cause of the problem, but I have seen where the O2 sensor wires got switched after engine replacement . This isn't too hard to do , and is just a thought. To verify something like this a wiring diagram and being very thorough are required.

 

I took the injectors from passenger side and switched with drivers side thinking that if the problem was in the injectors then the lean and rich codes would switch banks. In the process of doing this I soaked the injectors in some gas for a few minutes then blew them out with air. I installed program for 89 octane fuel from jet programmer. Programmer cleared codes and so far no ODB11 codes. My guess injectors were dirty causing lean codes and computer trying to compensate for it was causing rich codes on bank 1 or vice versa. Hopefully Truck continues to run well. Thanks for your input Hanky and the O2 wires have not been reversed. If the truck continues to run good for the next few days I am going back to stock program. I have heard that jet programmers arent much, I use it as a ODB11 scan tool. Thought I would try one of programs just to see what happens. Thanks again for your input.

 

Ran truck for a few days while programmed the rich code in bank 1 has not returned although the lean code bank 2 has returned PO174. Cant seem to figure this one out still have rough idle and hardly now power on inclines of any kind. Short fuel trim 2 is in + double digits almost constantly. Short fuel trim 1 bounces between -3 and +7. long trim 2 + double digits while long fuel trim 1 about the same as short fuel trim 1. Going back to stock program but still neeed to figure out the lean code bank 2. Any suggestions. No vacuum leaks O2 sensors new, Maf and Air filter fuel filter all new all sensors new. Maybe a clogged injector or fuel pump maybe. thanks for any help.

 

What you might be looking for is something that is not common to both banks. Fuel press, MAF is common to both so would eliminate them.
If cleaning the injectors helped to correct the problem try cleaning the remaining ones.
Seems the ECM is trying darn hard to add fuel and it is just not getting in there.

 

whats a good solution to help in cleaning the injectors as I cant afford to have them cleaned professionaly and fuel additives arent helping either. The best additive I have used is Lucas FI cleaner. I too am leaning towards the injectors being dirty. Seem to have good pressure or feel like would have problem on both banks. Ok thanks again Hanky

 

There are many kinds of injector cleaning products available in "Regular auto supply stores". I know it isn't cheap to try one or two tankfuls of premium gasoline, but that may help clean the injectors. I would consider trying that first since you have to purchase gas anyway. It also requires the least amount of effort. We usually try the simple things first, what do you think?

 

Ive tried just about every kind of cleaning product I can think of. I know its a little expensive but what do you think about ZMax. Premium gas not to bad here about 324 gallon so not much different cost wise. what cleaners have you had the most benefit from. Firm believer in doing easiest first.