Considering long tub headers for upcoming mods, which Mfg./model of long tube headers do NOT give any DIC codes or problems with 02's (or any other code problems)???? I know a lot of the problems are from burnt/melted wires and I'm not asking about that situation.

 

I just did LG Streets with cats and both front and rear O2's. No codes no problems.

 

How many miles/weeks

 

I have the QTP's. No codes, at least up until they were edited out anyhow. When you go with aftermarket CATs, I think codes are inevitable. But the QTP's do come with Random Tech CATs and "X" pipe, very nice quality stuff.

 

I've installed every kind of header, they all seem to throw the code every week or 2 of the aft sensors, it's the norm until edited

 

So far no codes with my American racing Headers...but it has only been 4 days so far!

 

Appreciate the feedback, keep it coming.

 

Sent you an email

 

Iam going to completely agree with Steve here. I have seen just about every header out there get reports from people saying that they have 02 issues. I would love to figure out how some guys luck out and don't have issues. I sure do. Hopefully my tuner can turn these codes off and I will still be able to pass emissions.

 

It's not the headers that cause the code, it's either the deletion of the cats or the use of high flow cats.

 

ummmm not quite sure on this one? How is this so? My 02 sensors are located just after the collector and before the cats. The codes are for the 02 sensors and not the cats. The code is for a switching issue of the 02 and because its before the cats I can't see how the cats would have any effect on it.

 

You have 4 O2 sensors; 2 ahead of the cats after the header and 2 after the cat that monitor cat performance.
I've only seen one post from a person getting codes from the front O2's after a header install; the majority if not all the codes are related to the rear O2's which are behind the cats or the bypass pipe, not ahead.
The 2 codes people are getting after header install are P0420 and P0430 both of which refer to the rear O2's, not the front. Usually any other code will be due to an incorrect install.

 

I took a trip 3 years ago to the Vette Doctors......ARH w/high flows and a tune Not one issue You oughta think about running over there tsts

 

Sorry .... but you misunderstand the issue.

The catalytic converters (cats) are VERY sensitive to temperature ..... they want HOT gases from the engine to assist in the catalytic process. On a cold engine start the cats are too cold to catalyze the gases and take a while to come up to temperature before they start working (light off). Many Corvettes are fitted with "pup" cats that are directly below the stock manifold .... they heat fast and once they are working they reduce pollutants and help heat the main cats to get them to "light off".

Long Tubes are called that because distance the hot exhaust gases have to flow has been "lengthened" over the distance the stock manifold flows the gases. That added distance is enough to affect the performance of the cats, especially in cold start situations. The cats can take longer than the PCM is programmed to allow for "light off", which will set codes. The cats can be working, but not efficiently, which can set codes. The cats need to be VERY hot to work correctly .... usually above 800 degrees.

That's why there are ZERO LTs certified by the CARB as smog legal, and never will be .... the LTs do the opposite of what the cats are designed for and need ... to be as close as possible to the exhaust ports in the heads.

And that's why anyone with LTs is gonna get rear O2 sensor codes at various times with a "stock" PCM ..... and why many people with LTs have the rears "tuned out" of the PCM DTC checks.

 

Kook's LT with 3" hi flow cats and never have had a code in 5 years relating to emissions.
Maybe it's because Kooks keep the stock locations for the O2 sensors.

 

Ok let me clear a few things up as we are on different pages.

1. You said you have only found 1 post about codes? You need to search again! I'll gladly give you links to over 50 posts on 02 sensors and codes related to the front sensor banks as the rear banks everybody running headers knows you turn off.
2. You mention 4 02s. and with a stock system yes you have all 4. However when running headers, most manufactures only tell you to run 2. The rear o2's in the front positions. The rear 02 banks are completely turned off so its impossible to get any codes at all from those.
4. Iam not talking of the same codes as you mentioned. The codes Iam referring to are on the front sensor banks and are switching issues due to 02 sensors either heating up too quickly or not quickly enough. This is because of the new location of the 02's in the pipe. Hope this clears things up.

Please anybody having a switching code being thrown (P0153) for example. Chime in.

 

Just installed American Racing Headers. They use all 4 stock O2 sensors with no wiring extensions whatsoever. Everything hooks back up just like stock!

 

Millenium Z06 just curious as to what headers your running and did you get extensions to run all 4 o2's? On a side note, you mentioned the codes you were referring to had to do with the rear sensors and that those usually get tuned out. Are you referring to "not to report" or "tuned/turned off"? Cause Iam thinking if you were running all 4 sensors then had codes being thrown off by the rears causing you to turn them off, then you would be running only the front sensors once again and the rears would not be doing anything? Just trying to understand, Iam at desperation right now just trying to get rid of my codes.

 

There is a lot of information, experience and opinion above; I hope there is some sort of resolution to the original question. At this time, it seems the only sure way to avoid 02 and code problems for sure is to go with shorties or stock exhaust.

 

After the collector and before the cats? Why even have the rears at all? That would make them quite useless....