Hey guys. Got a p0151 code coming on. B2s1 low voltage. I have already replaced both o2 sensors in the last 2 wks. Gas mileage been bad for the last few months and no light till now has ever been on. Could the heating element be inoperative and allowing the sensor to read the correct a/f on that side? Returning car to stock tomorrow and taking it to Ford since they should fix it bc its not the dreaded #8 misfire code. Motor is good. Running on half power(didn't even want to try wot with the light on) this afternoon on the way home from work. Also this all started back when the car had 2000miles on it when I noticed the same sensor was slow to respond even on warm start ups. And its still this way after I tuned the car with steeda tunes plus still running +20% long term fuel trims. Would a leak at the intake manifold cause this lean condition? just looking for suggestions and if anyone has had this code come up also. Thanks in advance

 

so you have done no exhaust work to the car yet? Could be a bad connection or it could be moisture between the pig tail and the harnass. I replaced both 02 sensors myself and came across a thicket of moisture in my connector and with a little electrical grease i haven't had any problems since. What kind of 02 sensors did you go with? The only 2 of i know are motorcraft and bosch for the 2011 and up.

 

Roush axelbacks that's it. Used oem motorcraft sensors straight from Ford. Car is tuned by steeda and Doug at c&l. Checked connections this afternoon and were all good and plugged up. I swear its not heating up properly when first started up. Took it to ford today and they wouldn't even look at bc of the steeda intake. Blamed code on tune in car. I called ford customer service and rep I talked to said the dealership never wrote a ticket on the car or called warranty bc there was no record of it. No record of dealer even writing up the car much less calling to ask about the code. No flag on my warranty for car being tuned and was told that my warranty was still full and good thru 60k miles. And the lady at ford told me that it looked like I needed to go to another dealer and have car looked at. Returning to stock tomorrow and when it comes back on immediately I'm going to take it to another dealer. And see what they tell me. Seems easy for me to prove its not the tune if it turns out to be the heating element that's at fault. Tune doesnt control that.

 

I would think that any unmetered air from the intake (if there's a leak) could cause a lean condition. If another dealership thinks your steeda intake has an intake leak, this may go on the "record" and cause you some warranty grief. I'd double check the intake for any potential leaks before taking it into Ford to safely rule it out. As soon as Ford see's it, I'm thinking they will want to point at it as a potential cause. It seems rare that an O2 sensor would fail early.

 

Post a good pic of your intake. Sounds like a CAI deal. Possibly MAF issue.

 

Pic of the cai

 

I was hoping the MAF could be rotated. Make sure the element isn't pointed the wrong way. It's very easy to damage the element also. Might just be in the tuning too.

 

MAF can only go one way. I did check that the other day. And when I put it back tohether one of the tubes wouldn't go all the way back in as far as it was. Bout to take it off again and check that.

 

Yeah that thing has to be exact. Those CAI's can be more trouble than they're worth sometimes.

 

Its a low voltage code. Not a lean code. I would point at the sensor. If it was an intake issue both banks should be throwing a lean or rich code

 

Is it a low voltage code? I didn't look it up. That's a different story.

 

Lol read first sentence first post

 

READ? No thanks.

 

Texasboneking which side is bank 2? Is it the drivers side?

 

Pretty sure yes

 

Bank 2 should be passenger side unless Ford is backwards.

 

Cylinder 1 is on passenger side so I figured that was bank 1

 

No, GM is backwards. Don't you read L to R?

Ford - #1 is passenger side (facing engine)

 

Like I said its a Ford. Lol. On pretty much everything else bank 2 is passenger side. We're gonna need a ruling. Just looked into that code also. Gonna take some circuit testing. I would return it to stock tune with stock CAI and see if the problem disappears.

 

Yes but is that bank 2? Paul! We need a ruling.