Dodge: 1996 Dakota 3.9 v6 stalls after warm, chevron techron, haynes manual

Question
Hi!

I have a Dodge Dakota VG 3.9 that pops and bangs intemittently and stalls after I shut it off after the intial start up for the day.  I does have a check engine light which states codes 51 and P0171 these indicate a lean gas mixture and low voltage condition in O2 sensor.  I have a haynes manual and checked voltages.  They all seem OK.  Then, my check engine light went out for a while now it is back on.  I find the fuel filter is in the tank and not aftermarket item.  I have dumped some Chevron Techron cleaner in a couple of times.  What do you recommend I do for this intermittent fuel related issue.  Th O2 sensors are spendy, and the fuel filter looks like a challenge.  I also found I can not run the higher octane fuel.  I really runs rough.

Thanks!

Answer
if the truck is popping and banging as you say.You need to check the timing it sounds like the timing is off.Yes they are pricy but if the engine light says that's what it is then more than likely the problem will not correct until it is replaced.Having to replace anything inside the tank is a challenge,the tank will have to be removed to do it.I'd replace the o2 sensor if i were you to repair the problem.