about how many miles before tune?

[tav8ws6]

im sure this has been posted but i cant seem to find it

anyways, ive re-done my exhaust from headers back and i have left the rear O2's unplugged because the tuner im going to deletes them however the front ones are still in. Ive already driven about 200-250 miles but then i parked it. The SES light is on but everything seems to be fine. it revs and goes without hesitation even when i floor it. Its and A4 by the way. So how long do i have before my motor starts to crap out on me? or will i be fine? thanks alot

[slims00ls1z28]

It's just not reading from the rear o2's. It'll just make it run a little rich. I've had SES light on mine a little over a year now after my o2 sims failed no porblems yet.

[bigcraig987]

It is my understanding that the rear o2s do not affect mixture and are purely an indicator for if the cats are working properly and the car runs a bit rich after long tubes due to the front o2s being farther down the pipe. If it is otherwise somebody feel free to chime in. It will run better with a tune but will be fine with being a bit rich. Most people decide whether to have it tuned after long tubes based on preference and if there are other mods coming soon. So if you are planning on something like a cam in the near future I would say wait until after that otherwise it is just up to your preference.

[BlackLT1Z28]

Well, the engine is running rich because its more efficient. It breathes better, and therefore, donesn't have to work as hard for the same pumping action. So, the same amount of fuel that it needed before is a little too much for the setup now. The SES is just the O2 reading. Shouldn't cause any problems. If you want, go to autozone and have them check the code, if you just want to make sure.