Service engine soon light is on. Can i turn it off? Causes?

[PronksBonne]

Hey guys, was wondering if anyone could fill me in on what might be wrong here. My service engine soon light has been on for over a year now. The cars been running fine. Only modification ive done is FWI. May the air flow have anything to do with this? I have emissions test coming up, and I dont think itll pass with this light on. Any info would be greatly appreciated. Also I might add that sometimes i start my car and it doesnt turn on for a while. I unplugged my battery last week and i believe it stayed off for 2 days. Now its back.

[MrPOPE]

although your car may be running fine... something is throwing a diagnostic code. You can run over to AUTO ZONE and have them read the codes... then come back here and let us know what codes you are showing and we can better help out.

[crash93ssei]

^X2.

Most auto parts stores now can scan your car for free and give you the code. Do that and let us know what the code is.

[nos4blood70]

Let us know what code it is throwing, and then we can figure it out.

[PronksBonne]

Hey guys thanks for the relpies. bought a code reader.. it has the capability of deleting, so i deleted earlier. after driving about 15 minutes it did come back though. Is this the o2 sensor on the intake?? Thanks in advance


p0140 sensor circuit no activity detected bank 1 sensor 2

[2000Silverbullet]

It's either the oxygen sensor or the CAT. All that extra flow from your intake has had an effect.

[PronksBonne]

Thanks for the info! Would this be picked up on an emissions test even if i was to clear it before hand? Also Is there a fix to this problem/does it have any effect on the car?

Thanks again
Mike

[Archon]

Odds are, depending on their testing methods, that the car will not pass inspection. The rear O2's main purpose it to check the condition of the cat. It also plays a minor role in fuel adjustment. First course of action would be to replace the sensor.

[PronksBonne]

Should I buy a high flow cat to replace it with? Or is that overkill?

[Archon]

If it becomes necessary to replace the cat, sure you could buy a high flow. If you haven't experienced any drive-ability problems, replace just the sensor first.