SES light not comming up after CAT delete.

**Juanmiguel** · 05-11-2010

It's been now over a month I think that I installed my DP and deleted the cat. The SES light hasn't come up because of that. I think I read that it took a few days for it to come up but it hasn't and I drive the car every day, atleast a couple hundred kilometers each week.

The only way to set that code to "not report" is with a PCM programming thing and not just with a code scanner right?

Any ideas on that?

Thanks.

**blueguy** · 05-11-2010

Right...you have to set it to NR via a tuner.

Sometimes people haven't gotten an SES from it...its kinda just dumb luck sometimes.

**Juanmiguel** · 05-11-2010

ok I see thanks LoL...

**nawarkk** · 05-11-2010

Has you SES light come on before? Might wanna check it because we just found out there was no bulb for the SES light in my old GT when we bought it...

**Juanmiguel** · 05-11-2010

Yeah it used to come up a lot back when the CPS was faulty and the spark plug wires were like bubble gum. It also comes up before i turn on the engine.

**GeosGP** · 05-11-2010

Do you have the sensors plugged in?

**NaturallySmashed** · 05-12-2010

if they're not plugged in shouldn't they come up? maybe his car didn't get the correct driving pattern for diagnostics? maybe i'm crazy?

**GeosGP** · 05-12-2010

Yes, they should come up. But I've seen where folks keep them plugged in and zip-tied to something underneath the car.

**Ibwrong** · 05-12-2010

If you deleted your rear O2 it will eventually come up just a matter of time, but if you left the O2 welded into the pipe back there you should be fine.

**GeosGP** · 05-12-2010

Originally Posted by Ibwrong

If you deleted your rear O2 it will eventually come up just a matter of time, but if you left the O2 welded into the pipe back there you should be fine.

It could throw a cat efficiency lower than expected light, or some such. But at this point, who knows?

**gtpinsc** · 05-12-2010

if it was gonna throw a code, im pretty sure would have by now... my p0420 comes back within 2 days after i clear code.

**GeosGP** · 05-12-2010

Usually happens on the second startup. Usually. I'm wondering if the bulb has burnt out since it was on so much with that CPS issue.

**nawarkk** · 05-12-2010

Yea check that out too, not that hard to take apart. The bulbs are small and expensive lol $5 for only two of em and they're no bigger then a penny lol

**Ibwrong** · 05-12-2010

Originally Posted by GeosGP

It could throw a cat efficiency lower than expected light, or some such. But at this point, who knows?

Good point didnt think about that..

**Juanmiguel** · 05-12-2010

The O2 sensor is in place, only the CAT is gone. SES bulb is fine, it also turned on not long ago when I left the fuel cap opened. i'll double check later. If it's not throwing a code because the CAT is gone I'm fine with it. that light being on all the time bothers me a lot lol. I was just wondering why it didn't threw a code. My next mod will be a PCM anyway. Thanks for the replies.