Kingdog

Hello
I have searched and searched for a answer to the O2 sensor problem after LT header install. I have installed Dynatech LT's w/ high flow cats, Banks Monster single, AEM Brute Force, Interceptor gage and Nelson Tune. I have a 2004 GMC CC 5.3L. The problem that I have is S1B2 O2 is sticking at one value any where from 50 to 875. I installed New bosch O2's and spark plugs during header install. There are no leaks in the exhuast and all wires are connected to plugs. I had no problems prior to the installs. I tried replacing Bosch with stock AC Delco but no change. I moved all O2's around but no change. I have pulled up these codes multiple times P0154 and P0155. Now two more P0156 and P0157 in the last week. I'm also Misfiring #2 consistantly and my MPG has dropped 4 mpg driving it like a baby. Can someone give me some direction on the correct way to fix this problem? Thanks Kingdog

dewmanshu

iTrader: (4)

There should be plenty of threads on this. Nevertheless, you have caused the exhaust stream to be cooler on the o2's. Their little heaters are really on designed to heat them up so you can do start up and cold idling (other technical reasons like o2 sensor readiness tests and such). After which, the hot exhaust stream will help keep them "active". You need to heat up your exhaust stream by either wrapping the headers (not very aesthetically pleasing) or replacing the o2's with o2's that have hotter heaters, like the rear corvette sensors. Coated headers sometimes work, but not always. It's really a crap shoot depending on your vehicle and the atmosphere in which you normally drive.

Your MPG is dropping because of the inefficient reading of the o2's. The pcm is going to default to the safe side when in error. That safe side is more fuel. I am sure your fuel trims are in plus territory.

Kingdog

dewmanshu Thank You for the information. I have ceramic coated headers so we can scratch that off. Do you know what year, model or part number of corvette O2 sensor that works with the cooler temps? I have read this before but again I cannot find specific numbers. Thanks Again! I'm in panic mode due to moving 2600 miles in 2 weeks. I don't want to blow her up haulin my trailer with everything I own for 4 days straight. Kingdog

dewmanshu

iTrader: (4)

You won't blow up. It will just start to run crappy because of the over fuel.

Try a denso 2344617 sensor. That should be the vette rear sensor. It probably won't have the correct harness on it to plug into yours so you'll have to splice your harness plugs onto them from your sensors. Sounds wacky but use solder and weather proof shrink tube and it will be fine.

Once you are done, if you don't have a tuner or way to reset your fuel trims leave your battery unhooked for 5 minutes (10 minutes for good measure). This will reset your fuel trims. It may run crazy for a fuel miles but it will "learn" the right way to idle.

Remember, this works for some and not for others. It's not a guarantee. There are two other codes that are common with this and they may sneak up on you as well.

I personally think for the money they charge for Dynatech headers ( I have the old style) they should better engineer the collector and the o2 location. I know that sensor could be forced into a better stream of exhaust.

dewmanshu

iTrader: (4)

looks like amazon has those fuggers pretty cheap.

Kingdog

dewmanshu I'm all over these. I have been doing the forum thing for 10yrs and I just cannot find stuff on this forum. Thanks for mapping out my solution. I have a buddy w/ a 2000 4.8l, same setup and no heat o2 problems. He did melt one of Dynatech cats pre Nelson tune. Thanks Again and I will keep you posted!!! Kingdog

dewmanshu

iTrader: (4)

I was doing some research on this last night and I found that Denso's website doesn't list that part number as a corvette sensor. It is listed on JEG's site as a chevrolet sensor though. As long as it heats better who cares what it is designed for but I sent Denso an email about it all. IF they respond I'll post up their reply.

Don't worry about forum searches, sometimes I suck at it and other times I don't. As long as you try to solve on your own in my opinion you'll learn more than just running to a forum and posing your question. If you can't find what you need, hit everybody up for assistance. Yeh keep us posted.

09sierra6.2

could be wires or a coil on the misfire.. it may not look like the wires are bad but seen it many times, but if you've changed ithem then thats not it.. also move coils.. like #2 to #4 that way if the misfire moves then there you go one problem solved..JMO..

budhayes3

iTrader: (19)

Could be, or it could be related to the O2 sensor issue that he's having.

I used to have the PN for the Bosch Corvette O2 sensor, but since I moved a few months ago I can't seem to find anything. I tore up my room looking for it last night after reading your thread. Personally, I hate Bosch electronics though, and if Dewey can hook you up with a Denso sensor, I'd definitely jump on that one, even if it were twice the price (which it won't be, it will probably be half the price...I got Denso direct replacement O2 sensors for my truck for $37 each from Rock Auto dot com )

Kingdog

Well, I ordered and installed Denso #2344617 O2 sensors and no change. S1B2 is still Lazy. Is there any other reason for this sensor to stick or be lazy? Do I have any other options? Thanks Kingdog