kevins01silverado

So i have a 2001 silverado and i would love to do some long tube headers but there is one hold up. the fear of a check engine light or any other lights due to emissions. the headers i have been looking at are from ebay and supprisingly have good reviews on here but noone goes into any detail if it will turn on a MIL light. If anyone could help me out here itd be great. These headers have resonators or cats, im not sure which Stainless Racing Manifold Header Y Pipe Exhaust Yukon Sierra Chevy Suburban GMC | eBay thanks kevin

03sierraslt

iTrader: (22)

If it does not have functioning CAT's then it will throw a MIL light, you can get the light turned off via a custom tune but the CAT readiness checks will not complete and depending on state it will not pass emissions. I am willing to bet those headers do not have CAT's, they are most likely there for looks but hollow inside.

kevins01silverado

I did some further researching and found out that they aren't cats they are just resonators. So like you stated basically for looks. So anyways if I get a custom tune done to delete that about how much should it cost and who should I go to? I've heard great things about black bear. But is it a guarantee that I should have no worries of failing the obd2 testing?

03sierraslt

iTrader: (22)

It depends on your state when it comes to whether or not it will pass. If the rear 02's are turned off then the readiness test will not complete, so it will not pass if your state requires all readiness tests to pass. In PA where I live you can have one readiness test incomplete, none failed. So if the light is on for the rear 02's it will fail, if you have the code set to not report a error and no SES light then It may pass like I said depending on your state. You need to find out your local Emissions laws.

kevins01silverado

I am from new york and im not quite sure what readiness and all of this means, although i do know that when i get my inspection here that there is no sniffer hooked up it is just the ob2 cord and a visual sometimes. there is no sniffer, so basically what your sayingthough is it depends on whats turned off and whether or not its allowed to be turned off in my state? thanks im new to this haha

03sierraslt

iTrader: (22)

They do not use a sniffer on newer vehicles anyway around me, its all through the computer. Find someone you know that may be able to find out or knows a insp. mechanic. There has got to be a place to search it online but I am not sure where.

kevins01silverado

yeah i actually did NYS inspections when i worked at jiffy lube last year, its just idk if the computer scanned for stuff like that cuz i never really had any problems inspecting stock cars

AKlowriderZ71

iTrader: (22)

You performed the inspections, but don't know what you were looking for??

kevins01silverado

I didnt have my inspectors license.. a car would come in id check wipers, suspension, lights, brakes and fluid levels, plug in obd2 for inspection, start car and the computer walked me through like 6 screens and all i did was hit enter, yes and no, scan sticker nand put it in window. never knew what exactally the computer scanned and whether or not it could pick up if you have changed your 02 sensor and emissions settings

03sierraslt

iTrader: (22)

Trust me, the computer is scanning things. It looks for set codes and checks the readiness of various systems. Evap, Catalyst, missfires.. I don't remember the rest of the top of my head.