03 Durango 4.7 Fuel Mileage Issue
#1
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So I've been having a weird fuel consumption issue just driving around town and thats what seems to have taken the biggest hit. I look at my scanner and on the highway it's in closed loop and both b1s1 ans b2s1 are -5%/+5% at times with jumps around -10 and +10. The engine is in closed loop but when i get to off the highway and cruise in town it goes to open loop and at idle too. B1s1 reads 0% lobg term is like 5%. Engine coolant temp is at 208f and after a 25mi drive on the highway I would think it would stay in cold loop. My tool says open loop due to insufficient engine temperature so that confuses me. Any thoughts. Original o2 sensors. 290k
p.s, i do have the p0344 code and have replaced the sensor with a oem mopar but looks like i need to take it into the dealer for the tsb for the issue which is just a reprogram. Would that cause it to not stay in open loop during around town driving?
p.s, i do have the p0344 code and have replaced the sensor with a oem mopar but looks like i need to take it into the dealer for the tsb for the issue which is just a reprogram. Would that cause it to not stay in open loop during around town driving?
#2