No-tune w/ LT headers-CEL?

[2SSRSinBama]

I threw P0430 and P0420... every car i've ever done exhaust work on, threw those 2 codes, lol

I even named then before I read them, lol

have a OBD-II handheld scanner so erasing them is a matter of 15 seconds, until I get my tune on

[Tampa Tuning]

the LS2 motor is the best stock tune from the factory. I think they perform the best out of the box compared to the rest of LS series.

the other GM performance vehicles at WOT are in the upper 11s lower 12s AFR at WOT with about 6 degress of knock.

lets say you just did all your bolt ons and you get a CEL because of your headers changed your cat configuration. If you only wanted your tuner just to click off your O2 sensors, he can do that.

BUT, if your spending $2000 on aftermarket parks, spend the $300 for a tune. If your worried about a powertrain failure and a your warranty claim (bolt ons and under you shouldnt have any issues), dont modify the vehicle
www.TampaTuning.com

[The SwiftChancelor]

Originally Posted by axis

I drove mine for two weeks before it got tuned and never got a CEL. I've seen people post they got several hundred miles before the CEL as well. I've NEVER heard of anyone NOT getting a CEL at some point.

Same with me. I drove it for awhile before I tuned and didn't get a light except for when I didn't realize I forgot to plug a spark plug back in.

[axis]

Originally Posted by justa25thTA

the point of the tune is to NOT HAVE any excess fuel.

Originally Posted by Bell040

this is incorrect, that would put you over 14:1 A/F... and you will be burning up your rings at WOT. A tune optimizes the amount excess fuel... it by no means eliminates it.

Your tune is designed to put just enough excess fuel in the combustible mix during WOT to keep things cool (pistons, rings, walls, exhaust, cats, etc.).

......Your tune is really only for WOT in open loop control.... since your car is in a entirely different control mode during regular driving (open vs. closed loop control).

If you are driving around town in closed loop mode... and you think you smell excess fuel, its not. It is the inability of your cats to chemically convert the exhaust gas into CO2 and H20. It is most likley not gas... the smell is CO, NO, NO2, SO2, etc. Closed loop control is a totally different beast.

Thanks for explaining it Bell.

[2SSRSinBama]

Originally Posted by Tampa Tuning

the LS2 motor is the best stock tune from the factory. I think they perform the best out of the box compared to the rest of LS series.

the other GM performance vehicles at WOT are in the upper 11s lower 12s AFR at WOT with about 6 degress of knock.

lets say you just did all your bolt ons and you get a CEL because of your headers changed your cat configuration. If you only wanted your tuner just to click off your O2 sensors, he can do that.

BUT, if your spending $2000 on aftermarket parks, spend the $300 for a tune. If your worried about a powertrain failure and a your warranty claim (bolt ons and under you shouldnt have any issues), dont modify the vehicle
www.TampaTuning.com

exactly... if you have a L99, the tune is the single best mod you can do out of the box, that ALONE makes the car a whole new animal... headers and a tune? awesome... now i'm wanting a cam

but for your money, headers and a tune are where its at... i'm still on the stock air box right now... about to finally pull the trigger on a CAI and ported throttle body, but knew that headers was where it was at... I can get the other two later, wanted the big gainer of bolt-ons 1st

[1sikRS]

This same question is seriously beaten to death already

[Li0nel1234]

ARH 2"/3", HF cats, 3" exhaust,

Had it for about a month, few hundred miles, no CEL yet... =] But I'm getting it tuned soon anyways.

[Fraxum]

Big Flow LTs
Big Flow Cats
O2 spacers = Yes
Tune = No
CEL = Yes
Read codes, don't care. Priceless.

[bngummow]

Originally Posted by Fraxum

Big Flow LTs
Big Flow Cats
O2 spacers = Yes
Tune = No
CEL = Yes
Read codes, don't care. Priceless.

i might just end up taking this path...car is still under warranty cause it has no tune right? have you brought it in? how do you check your cel codes?

i like the motto haha

[Li0nel1234]

My CEL just popped a day or two ago! So now to go to Autozone to get the codes read or call onstar to have them tell me.

[2SSRSinBama]

I will say that I didn't need any O2 extensions with the Doug Thorleys, the factory length was plenty long enough...

use to you could run an o2 extender plugged into the o2 bung using a spark plug antifouler and even with a high flow cat or no cats and it wouldn't throw a code... that works on a lot of cars, including LS1 f-bodies... but with the newer GM cars, even pulling that old trick, it still seems to throw codes, here is one I made years ago and it worked to success with no cats, I threw several codes, made this, installed it and NEVER got another code in the 2+ years I owned the car after installing this simple little mod I created using $4 spark plug antifoulers from Autozone:




just screwed that into the exhaust pipe where the o2 sensors plugged in, screwed the o2 sensor into that, and for some reason that extension was enough to confuse the ECM and not set off a code... I think that trick was 1st discovered on the 350Z forums and then word got out, but I can confirm it worked on GM cars up to the LS1 GTOs... now I had a turbo Cobalt with no cats and tried this and it did NOT work, had to go to the ECM and have the codes removed(or the high and low threshold set the same which disables it)

[dragon22]

ARH LT headers with hi flow cats. Put 4000 Km on it with no CEL. Have it tuned now and the tune DID make a big difference even though I had no light. After you have it tuned you realize it really wasn't running properly. Thank you Ted Jannetty!