I just put OBX LT's with resonators on my 2006 5.4 with 86k miles. It has the resonators right after the header collectors, then has a y pipe, then a piece of stock exhaust pipe about 10" long that connects to a Roush SIDO (cat)back. I have the P2195 code, which means my passenger front O2 sensor is reading or stuck on lean. I'm going to try to include as much info as possible.

First, I am trying to refrain from driving my truck as much as possible because I don't want it damaged from running lean. But sometimes I have no choice. It's been driven maybe 15 miles max so far. But my work is 25+ miles round trip and I won't have another car to drive soon. My truck is my child and I'm concerned for her safety lol.

I have a Gotts mod that has been on the truck for a few months and never had an issue with it.

I have an SCT from 5Star with custom tunes that have accounted for the long tube headers and gotts mod, and has my rear O2's turned off. I loaded one of the tunes a few days before installing the LT's just to make sure everything loaded up properly. I left the tune on and it is currently still on the truck. I never had any issues with the truck running on the tune prior to the installation of the headers.

Currently the truck has the bungs/holes in the rear of the resonators open. This is leaking exhuast. I am working on finding some plugs to stick in there. There are 6 holes for some reason, but only four O2's. The front O2's are in the front most holes, the middle holes are open, and the rear most holes have the rear O2's in them (these O2's are disconnected). Could any of this cause the code?

My O2 sensors were working properly (to my knowledge) prior to the install. I was very careful handling them, though I just used a regular 7/8" wrench instead of the special tool to uninstall and install them. Could I have damaged the passenger side one somehow? I have checked and all of the connections seem good and no wires are pinched or squished. The front O2's have the BBK 1676 extensions on them.

If I clear the codes, I get no check engine light for the entire time the truck is running from the next start up. However, the very next start up after that will yield the P2195 and it will stay on.

The truck seems to possibly be a bit down on power, definitely doesn't feel like I gained 20+ horses like I was supposed to. This could just be attributed to the extra noise and my fear of really getting on the gas pedal, but I'm unsure.

I haven't noticed any rough running, but I've barely driven the truck. I can't tell if the exhaust smells rich (I know, opposite of problem) or unusal because I don't have cats, so it's inherently going to stink

If there were an issue with my intake system or the Gotts mod, wouldn't both banks be reading lean?

Could my tunes possibly be causing the problem?

I'm going to swap the O2's (left to right and vice versa) in the morning, clear the codes, and see if I get P2197 (Driver bank running lean).

I apologize for the length of this, but I was trying to be as thorough as possible. This header swap has turned into a $2,000 PITA nightmare with all the issues I've had. I'm running through as many checks on different things as I can. I will update with any findings

 

I bet the open bungs are your issue. You have an exhaust leak and its affecting the 02 readings I bet. Unfortunately both email tunes, unless you monitor the parameters, you don't know.

 

Sounds like you are having the same issue I had. But mine was the driver side and mine was bad because the exhaust guy that put in my headers hit my O2 sensor with a hammer to bend it to fit and broke it. (also unwilling to pay for it to fix what he admittedly broke it)

There is a possibility the sensor is bad, or the extension may be bad.

I also have a feeling that you leaving the bung holes open is causing this. Anything upstream from the y-pipe that is leaking will usually throw a code.

 

Ok guys, I was thinking it was the open bungs. I did think it would've triggered both sides if that were the case, but vehicles never do what you expect! I just had to document all of this as soon as I could. I'm going to have something in those holes by the end of the day.

Truckguy, what did you mean to say about the email tunes? That they could be bad or they could've contributed? Or something else?

 

You don't know how the air to fuel ratios unless monitor them.

 

How would I go about monitoring them? I had figured that since I had the tunes on for a couple days before the headers went in, and there weren't any problems, that they were fine.

 

Wideband and laptop software. I'm just saying, you don't know for sure how spot on that tune is. It's probably the exhaust leak but that's the issue with mail tunes imo. I do have one, but I had the stock Gryphon tune altered slightly to be safe.

 

Ahh. I can ask Mike to take a look at them if I can't pin point the problem. I would've preferred a stock tune that was only adjusted to mesh all the different pieces together. I don't like performance tunes that screw with things too much

 

I swapped the O2's left to right and right to left. It's still throwing the passenger bank. So I guess my sensors are working fine, but that's bad news as far as I'm concerned

 

I would get something to plug up those holes, reset the battery and see if it does it again. If so then you can start looking into A to F ratio.

 

I ordered plugs a few hours ago, hopefully that will fix it. If not, I'm gonna swap the extensions and see what happens. Then I'll look into the A/F. But isn't only the sensor stuck on lean? Meaning it just isn't switching between rich and lean? I don't even really understand why it switches or what that signifies, guess it's its way of regulating the A/F?

Does this issue mean that my passenger bank is actually running lean and that this faulty O2 is telling the motor to do so? Sorry for a bunch of questions, kind of me thinking aloud

 

Got plugs in last night! I figured I'd check all the connections again, just to be safe. And of course . . . One of the O2 extensions barely stays plugged in . . . One tug and it pops right out! So the damn thing was never really plugged in the first place. Smash them together, grab some electrical tape, problem solved and all is well.

I feel like a complete ***, but I'm not the one who initially installed the extensions. That was done by my shop. I didn't think to yank on the connections, just make sure they were smushed together. It's like going over an entire broken tv and checking everything, only to find that the thing isn't even plugged into the wall socket! I apologize for all of the trouble and am greatly appreciative of all of your help.

 

Hey atleast your problem was easy and nothing major. Glad its all fixed.

 

Me too, just feel stupid! I made such a big deal and stressed about the easiest thing! I was gonna be pissed if I had to track my AF ratio and keep delving deeper into it haha. This threa won't be of much help to anyone else down the road either

 

There are alot more useless threads on here ha.