My 2002 dodge ram is throwing a P0171 trouble code which means System to lean (bank 1). Anybody know what bank 1 refers to? the truck will run fine for about 40 miles or until it is warmed up completely then it starts hesitating and doesn't want to run anymore. i let the truck sit and cool, it runs fine. motor or computer? if it was the motor i would lead to think it would do it all the time but this is my first time to ever see or hear of this sort of problem. any help would be appreciated

 

i had the EXACT same code. except my truck was spewing black smoke. all i did was change the o2 sensor before the cat and problem solved. the code doesnt come up anymore nor does it smoke. when i put the new sensor in though, it took a few hours to reset the computer i think. because it smoked for a lil while longer but no more. hope this helps.

 

how did you find out it was that specific O2 sensor?

 

You ar elooking at a cat issue on the left(driver's side). what is happening is by what you are saying your cat is clogged which in turn it's not alowwing your motor to push the exhaust gasses out thus pushing back into your motor creating the bogging effect as if your motor is chocking. Thus your loss of power. Like I said by what your describing it sounds like your cat. Good luck let us know.

 

i found out it was that specific sensor because i read oin the shop manual i downloaded that the o2 sensor brfore the cat, (i have 4.7, one cat) controls the air fuel ratio. since it was black smoke, i figured it was running rich, this is the only non-carburated truck ive had and black smoke to me has always meant running rich. i replaced the sonsor (same code as chrisfred) and problem solved. although i would take 1baddodge's advice since when i had this problem there was no loss of power or chance of performance. my truck has 120something thousand miles on it so my sensor had to go anyway.

 

While I agree that this could very well be a O2 issue, I also would strongly advise at least pulling a couple of plugs on the drivers side bank (bank 1) and checking to make sure you aren't actually running into a truly lean condition. A lean condition can lead to a burned piston or valve leaving you to face what could be a near complete engine rebuild (sucks!!!!!) and a lot of money that doesn't really need to be spent. The reason I'm telling you this, is because I guy I work with has a 2000 ram 5.9L, and he was first hand witness to rust plugging his injectors screens at the inlet side of the injectors, causing the same problems you are describing, although his were on all eight cylinders. I would think that in the current generation of 5.7's, that if the voltage feedback to the PCM were incorrect, it might throw a code indicating a bad O2----but I could be WRONG HERE ALSO!!!!!!!! Pull the plugs and check---it could save from rebuilding your engine, or it could be a simple faulty O2


Good Luck!!!!!!!!!

T

 

what do you guys think would make the truck run perfect when i first start it but then after a 60 or so miles it goes to crap.

 

for the record these problems are taking place with my 2002 Ram QC 4.7L 2WD w/ 123,000

 

With that kind of mileage, its the sensor.

 

I took my truck to the dealership yesterday and the service writer told me that the O2 sensor would NOT make the truck die, it would just make the truck run like crap. I was told that the fuel pump was culprit. the only fuel filter the truck has is the sock on the pump in the tank. Which is not replaceable (smart engineering). Also running the truck to the very bottom of the gas tank will cause the pump to cavitate when i turn corners (this is what i was told), but at the same time makes sense. Decreasing the life of the pump. The service writer was surprised that my pump made it as many miles as it had (123,000) so i guess fellow dodge owners beware. I have installed the new pump today, but i have yet to drive it. So stay tuned for the results...