Nearly every O2 Sensor Code & P0101

[CaptKirk]

Little background on what's up with the truck/exhaust:

 

since I bought the truck 2 years ago, every so often it would give me a random 02 sensor code for somewhere between an hour to a few days, then clear itself up. No change in drivability, never bothered me.

 

Fast forward to 6 months ago, I have the truck up in the air investigating a "loose heat shield" that I'd hear clanking occasionally over bumps with the windows down. Turned out to be my exhaust that had rusted in half, the backside was pivoting on the hanger and bouncing on the rear end. So I figured that was the O2 sensor code from the terrible exhaust leak. Anyway, I pulled that part of the exhaust off and have been cruising around with one half my exhaust dumped right after the muffler since, with intentions of buying a new exhaust sometime soon.

 

Fast forward to about a month ago. Been distracted and still haven't bought an exhaust. I had to drive through some high water because it floods like a mofo here in Houston, truck is my DD. Not right away, but a few weeks later my CEL came back on and I figured it was the same, but after some driving I could tell I was down on power a little bit. Sometime when using more than half throttle at about 3600 RPM you can feel it return all the power. So I read the codes and now I have basically every O2 Sensor code... P0131, 0137, 0151, 0157 (twice, each bank) and P0101.

 

Did some searching on what others did to try to fix...pulled/cleaned air filter, MAF, and TB, no difference. Nothing but the air filter was particularly dirty at all, in fact they were so clean I'm rather suspicious this isn't the original motor with almost 150K miles on it. Cleaned it anyway though.

 

So, basically. I still have all these codes, my truck has quite a bit of rust underneath (most of it's life was in the north), so I'm fairly convinced it's further rusting/exhaust leaks in the (magnaflow maybe?) exhaust that came on the truck when I bought it. Although the MAF code (0101) has me worried it could be more than exhaust...?

 

Curious what yall think, is there something else I can try?

 

I'm going to replace the exhaust regardless, is it worth it to try and reuse the O2 sensors? I don't really wanna replace 4 (6?) at 50-100/pop

 

Also, any recommendations on a quiet, deep toned exhaust with dual exits (not a two pronged tip) either before or after the rear tire? I'm unsure if I need mid-pipes...would rather go catless if mine are damaged, but will pay for them if deletes are going to be raspy regardless of exhaust choice. Praying I don't have to do headers too. I'd rather save my money for my project car not my DD. This thing drinks enough 93 as it is. Sure do love it though!

 

Sorry for the novel ^

Edited July 7, 2016 by CaptKirk (see edit history)

[2003_SuperSport]

Little background on what's up with the truck/exhaust:

 

since I bought the truck 2 years ago, every so often it would give me a random 02 sensor code for somewhere between an hour to a few days, then clear itself up. No change in drivability, never bothered me.

 

Fast forward to 6 months ago, I have the truck up in the air investigating a "loose heat shield" that I'd hear clanking occasionally over bumps with the windows down. Turned out to be my exhaust that had rusted in half, the backside was pivoting on the hanger and bouncing on the rear end. So I figured that was the O2 sensor code from the terrible exhaust leak. Anyway, I pulled that part of the exhaust off and have been cruising around with one half my exhaust dumped right after the muffler since, with intentions of buying a new exhaust sometime soon.

 

Fast forward to about a month ago. Been distracted and still haven't bought an exhaust. I had to drive through some high water because it floods like a mofo here in Houston, truck is my DD. Not right away, but a few weeks later my CEL came back on and I figured it was the same, but after some driving I could tell I was down on power a little bit. Sometime when using more than half throttle at about 3600 RPM you can feel it return all the power. So I read the codes and now I have basically every O2 Sensor code... P0131, 0137, 0151, 0157 (twice, each bank) and P0101.

 

Did some searching on what others did to try to fix...pulled/cleaned air filter, MAF, and TB, no difference. Nothing but the air filter was particularly dirty at all, in fact they were so clean I'm rather suspicious this isn't the original motor with almost 150K miles on it. Cleaned it anyway though.

 

So, basically. I still have all these codes, my truck has quite a bit of rust underneath (most of it's life was in the north), so I'm fairly convinced it's further rusting/exhaust leaks in the (magnaflow maybe?) exhaust that came on the truck when I bought it. Although the MAF code (0101) has me worried it could be more than exhaust...?

 

Curious what yall think, is there something else I can try?

 

I'm going to replace the exhaust regardless, is it worth it to try and reuse the O2 sensors? I don't really wanna replace 4 (6?) at 50-100/pop

 

Also, any recommendations on a quiet, deep toned exhaust with dual exits (not a two pronged tip) either before or after the rear tire? I'm unsure if I need mid-pipes...would rather go catless if mine are damaged, but will pay for them if deletes are going to be raspy regardless of exhaust choice. Praying I don't have to do headers too. I'd rather save my money for my project car not my DD. This thing drinks enough 93 as it is. Sure do love it though!

 

Sorry for the novel ^

Once you get the new exhaust maybe get a tune for $250 and have them delete the rear O2 sensors. If you have to replace them at $100 bucks a pop might as well spend the extra $50-$100 for a tune and delete the rears... Bad cats will cause running problems as well so while your in there do high flow cats or just delete those as well and tune it...

Edited July 7, 2016 by 2003_SuperSport (see edit history)

[eberhama]

I've got nothing to add to the code discussion, but if you go to rock auto, get the delco part #'s for the o2 sensors, then search them on ebay, you can get them for about $25 each for new delco ones. I bought all new ones for mine this spring.

[CaptKirk]

Once you get the new exhaust maybe get a tune for $250 and have them delete the rear O2 sensors. If you have to replace them at $100 bucks a pop might as well spend the extra $50-$100 for a tune and delete the rears... Bad cats will cause running problems as well so while your in there do high flow cats or just delete those as well and tune it...

 

I will look into that, sounds like a good alternative. There is just 4 correct? Pre/Post cats?

 

Can the stock ECU be tuned or do I need to purchase a piggyback? Sorry I don't know anything about this. I'll do some research

I've got nothing to add to the code discussion, but if you go to rock auto, get the delco part #'s for the o2 sensors, then search them on ebay, you can get them for about $25 each for new delco ones. I bought all new ones for mine this spring.

 

Perfect, thanks for this!

[CaptKirk]

Okay I got under the truck and took some pictures because I'm pretty unfamiliar

1. Can anybody recognize this exhaust? Custom?

2. With the codes explained above, do you think keeping the Y pipe and replacing the catback will fix the issue?

3. Will this fit an '03? It says 6.0 here but just want to confirm the part # with someone who knows it does. In my searches it sounds like Corsa will be too loud for my liking and magnaflow will be quieter. https://www.summitracing.com/parts/mpe-15840/overview/

 

I want the exhaust to stay quiet and not drone and I'd also like to not spend a fortune it's just my DD. So I'd like to keep my Y Pipe, cats, and O2 sensors if I can, however, I'd like to only go through this process once.

 

 

 

 

 

 

 

 

 

 

 

 

 

From what I can see, the O2 sensor wires look fine not cut up or frayed or bent weird... I know they could still have gone bad though

Edited July 8, 2016 by CaptKirk (see edit history)

[SS-GTP]

If I'm interpreting the photos correctly, it looks like you have dual mufflers with dual outlet pipes. That would not be factory, as from the factory you would of only had a single muffler with 2 inlets and a single outlet with a rectangular shaped tip. Missing that section of pipe after the muffler is not having any effect on why you would be getting codes. The rest of your system looks stock, but I can't tell how well it seals from the photos.

[eberhama]

Yep, that's just a muffler shop cat-back. The exhaust on the summit link says rear wheel drive only, not sure what would be different, but if it fits awd they'd be sure to mention it.

[2003_SuperSport]

 

I will look into that, sounds like a good alternative. There is just 4 correct? Pre/Post cats?

 

Can the stock ECU be tuned or do I need to purchase a piggyback? Sorry I don't know anything about this. I'll do some research

 

Perfect, thanks for this!

There is only 4 O2's 2 pre-cat and 2 post-cat. The rear O2's are not necessary to run and are only used to monitor that your catalytic convertor is working as it should. All four work in conjunction to communicate to your computer (PCM) in order to give you the best fuel economy and performance while being EPA friendly and quite frankly decreases performance and fuel economy to be more environmentally friendly. The catalytic convertor only hurts performance as it is a restriction of airflow but it is a EPA requirement as it sole purpose is to burn un-burnt fuel leaving the engine to keep all the happy tree huggers quiet. The front O2's are the only ones that are required as they take the exhaust straight from the engine before being re-burnt in the cats and tell your computer to adjust fuel trims and AFR in conjunction with your Map sensor and MAF sensor in order to run most efficient. Like I said previous post, old stock cats can cause running problems as the packing deteriorates or bust up or plug up inside the cat causing the rear O2's to send codes. Most of us with performance mods remove them completely and tune them out. If your state doesn't require a state inspection your best bet is to remove them or to replace them with fake straight through ones or just a exhaust pipe section.

 

The tune in itself will be a night and day difference in performance and you will see better gas economy as long as you stay off the skinny pedal... You can get it tuned at any dyno tune shop for $400-$600 or send it in to Zippy, Charlie Wheatley, or Black bear for $250-$350 who are the most common here. They will do just as good if not better than a custom performance Dyno shop especially for light to moderate modified vehicles. We have guys with mail order tunes running 10's in the 1/4mile from the mail tunes. Just do a little research and you will find all the info you need... If you do a mail order tune you need to remove your PCM located just under your alternator next to your battery and is held on by a snap and two bolts holding the pins into the PCM, super easy to remove and mail it to your preferred tuner. Takes 1-2 weeks turn around. If you cant have your truck down for that long they can send you pre-programmed PCM for an additional fee and all you need to do is send them your core. Once they receive your old PCM they will reimburse you the additional fee. YOU WILL NOT BE DISAPPOINTED IN A CUSTOM TUNE!!!! Plus most tuners will give you free or small charge retunes for as long as you own the vehicle in case you ever want to add more go fast parts like superchargers, turbos, or even cams and heads. A stock truck will benefit from a tune but a truck with full exhaust and CAI and other bolt-on's like yours will benefit a lot more, so much you will think its a completely new vehicle. It will run smoother and be twice as responsive all while gaining 2-5mpg more... The more you add the more you will need a tune to get full potential... Here is what I would do if I were you

 

1st and foremost- If I were you I would get a tune setup. That way you can get the O2's deleted and unlock the true potential of these trucks...

 

2nd- I would get your truck scanned and find out which O2 is giving you the bad codes. If it is both the rears then I bet the cats are giving out or you are just unlucky and both went out. If the cats are shot I would just cut them out and put in a straight pipe to fill the gap or put in a new high flow cat if your state tests for it and still tune out the rear O2's as they are not needed for running anyways. If it is the front O2's going out you can use the rear O2's and swap them because the rear ones would not be needed when you get tuned. Make sure to have the bung holes welded shut or leave the old unplugged O2's in the holes so no exhaust leaks.

 

3rd- Id probably get a new exhaust system as that one seems pretty ratty and rusted in spots and may only continue to spring leaks. But if your on a budget at least do a leak test to make sure all the welds and pipes are sealed up as well as the headers. Holes or leaks near the engine/headers or near the O2's will make the O2's read inaccurate also throwing codes. Most exhaust shops can do that for you for a reasonable price, or you can just listen and feel around with your hand for air leaks trying not to burn yourself.

 

Finally- According to your pictures, the cat on the passenger side looks different than the driver side. It may be your problem as it looks like it maybe getting a bit warm due to the discoloration and extra rust which is an indication it could be plugged or not working correctly as compared to the other side. I am not there to look at it or do the test so I could be wrong but it is worth looking into. Another sign you can test at home to see if they may be broke or plugged is after they have been running for awhile they may even glow red hot or much hotter then the other. Try not to burn yourself lol. Also be sure to check especially around the hanger welds as I have seen them break or crack causing leaks. I no longer weld my hangers directly to the pipe due to the welds rusting out overtime. Instead I attach an exhaust clamp to the pipe where I want to weld and weld the hanger to that. No more cracked or bust welds on my pipe .

 

I do like those mufflers as I run similar Magnaflow dual mufflers and they sound beastly under acceleration. Anyways good luck and I hope this helps you find the problems... Get a tune

[CaptKirk]

If I'm interpreting the photos correctly, it looks like you have dual mufflers with dual outlet pipes. That would not be factory, as from the factory you would of only had a single muffler with 2 inlets and a single outlet with a rectangular shaped tip. Missing that section of pipe after the muffler is not having any effect on why you would be getting codes. The rest of your system looks stock, but I can't tell how well it seals from the photos.

 

Thanks, I didn't think it'd cause a problem missing that part either that's why I waited so long to get another exhaust.. appreciate the help

 

Yep, that's just a muffler shop cat-back. The exhaust on the summit link says rear wheel drive only, not sure what would be different, but if it fits awd they'd be sure to mention it.

 

Yeah I had a feeling..okay. Do you know of a quiet magnaflow catback that'll fit AWD?

 

There is only 4 O2's 2 pre-cat and 2 post-cat. The rear O2's are not necessary to run and are only used to monitor that your catalytic convertor is working as it should. All four work in conjunction to communicate to your computer (PCM) in order to give you the best fuel economy and performance while being EPA friendly and quite frankly decreases performance and fuel economy to be more environmentally friendly. The catalytic convertor only hurts performance as it is a restriction of airflow but it is a EPA requirement as it sole purpose is to burn un-burnt fuel leaving the engine to keep all the happy tree huggers quiet. The front O2's are the only ones that are required as they take the exhaust straight from the engine before being re-burnt in the cats and tell your computer to adjust fuel trims and AFR in conjunction with your Map sensor and MAF sensor in order to run most efficient. Like I said previous post, old stock cats can cause running problems as the packing deteriorates or bust up or plug up inside the cat causing the rear O2's to send codes. Most of us with performance mods remove them completely and tune them out. If your state doesn't require a state inspection your best bet is to remove them or to replace them with fake straight through ones or just a exhaust pipe section.

 

The tune in itself will be a night and day difference in performance and you will see better gas economy as long as you stay off the skinny pedal... You can get it tuned at any dyno tune shop for $400-$600 or send it in to Zippy, Charlie Wheatley, or Black bear for $250-$350 who are the most common here. They will do just as good if not better than a custom performance Dyno shop especially for light to moderate modified vehicles. We have guys with mail order tunes running 10's in the 1/4mile from the mail tunes. Just do a little research and you will find all the info you need... If you do a mail order tune you need to remove your PCM located just under your alternator next to your battery and is held on by a snap and two bolts holding the pins into the PCM, super easy to remove and mail it to your preferred tuner. Takes 1-2 weeks turn around. If you cant have your truck down for that long they can send you pre-programmed PCM for an additional fee and all you need to do is send them your core. Once they receive your old PCM they will reimburse you the additional fee. YOU WILL NOT BE DISAPPOINTED IN A CUSTOM TUNE!!!! Plus most tuners will give you free or small charge retunes for as long as you own the vehicle in case you ever want to add more go fast parts like superchargers, turbos, or even cams and heads. A stock truck will benefit from a tune but a truck with full exhaust and CAI and other bolt-on's like yours will benefit a lot more, so much you will think its a completely new vehicle. It will run smoother and be twice as responsive all while gaining 2-5mpg more... The more you add the more you will need a tune to get full potential... Here is what I would do if I were you

 

1st and foremost- If I were you I would get a tune setup. That way you can get the O2's deleted and unlock the true potential of these trucks...

 

2nd- I would get your truck scanned and find out which O2 is giving you the bad codes. If it is both the rears then I bet the cats are giving out or you are just unlucky and both went out. If the cats are shot I would just cut them out and put in a straight pipe to fill the gap or put in a new high flow cat if your state tests for it and still tune out the rear O2's as they are not needed for running anyways. If it is the front O2's going out you can use the rear O2's and swap them because the rear ones would not be needed when you get tuned. Make sure to have the bung holes welded shut or leave the old unplugged O2's in the holes so no exhaust leaks.

 

3rd- Id probably get a new exhaust system as that one seems pretty ratty and rusted in spots and may only continue to spring leaks. But if your on a budget at least do a leak test to make sure all the welds and pipes are sealed up as well as the headers. Holes or leaks near the engine/headers or near the O2's will make the O2's read inaccurate also throwing codes. Most exhaust shops can do that for you for a reasonable price, or you can just listen and feel around with your hand for air leaks trying not to burn yourself.

 

Finally- According to your pictures, the cat on the passenger side looks different than the driver side. It may be your problem as it looks like it maybe getting a bit warm due to the discoloration and extra rust which is an indication it could be plugged or not working correctly as compared to the other side. I am not there to look at it or do the test so I could be wrong but it is worth looking into. Another sign you can test at home to see if they may be broke or plugged is after they have been running for awhile they may even glow red hot or much hotter then the other. Try not to burn yourself lol. Also be sure to check especially around the hanger welds as I have seen them break or crack causing leaks. I no longer weld my hangers directly to the pipe due to the welds rusting out overtime. Instead I attach an exhaust clamp to the pipe where I want to weld and weld the hanger to that. No more cracked or bust welds on my pipe .

 

I do like those mufflers as I run similar Magnaflow dual mufflers and they sound beastly under acceleration. Anyways good luck and I hope this helps you find the problems... Get a tune

 

That's almost sticky worthy!! Thanks for the great write up. That was really helpful and I'm sure others down the road will find it to be as well.

 

So the truck goes in today for an alignment and to check out the AC, so I'll ask about the cat deletes.. Texas does inspections, but I'm not sure how much they'll care about cats. On the other hand, since I want a quieter exhaust, I may do high flows

 

Thinking it over more, I'll just spring more bucks for some new midpipes, find a somewhat quiet catback, and get a mail order tune done.

 

Thanks again all for the responses. I'll continue to update this thread with the outcome of the sensors/exhaust

[70chevy03ss]

Can't help on codes but look into a dynomax x flow muffler. No drone and sounds great. Dual in dual out. Mine exited behind the rear tires into 4inch tips. I loved it on my ss

Edited July 8, 2016 by NoMoreSS (see edit history)

[CaptKirk]

So it looks like a lot of people just pick out the mufflers/cats/x-pipes they want and have a shop fab it up for them? It seems the corsa sport exhaust is really the only bolt on option and is too loud for my liking plus I don't really like single side exit...

 

Just new to doing exhaust this way...I'm used to having 10-20 options from different companies that bolt right up with no work to do

[jovanny]

My corsa touring is really quiet whem cruising or on the highway but turns into a different animal whem you floor it

[CaptKirk]

My corsa touring is really quiet whem cruising or on the highway but turns into a different animal whem you floor it

 

Yeah I've heard those arent too bad, but they don't make them anymore apparently just the sport

[eberhama]

I went with it Gibson, because it was the cheapest one out there. The fit and finish isnt super awesome but it works and sounds good. It a dual in single out, single muffler set up though.

[CaptKirk]

I went with it Gibson, because it was the cheapest one out there. The fit and finish isnt super awesome but it works and sounds good. It a dual in single out, single muffler set up though.

 

 

Thanks for the review!