check engine light on and off?? - Toyota Nation Forum : Toyota Car and Truck Forums

shaun3701 · 04-25-2006, 01:32 PM

Is this normal? My check engine light will come on for about a week and then go off again... then a few weeks later it will come back on for about a week... then go off again. When I got it checked out they said it was the O2 sensor... are they supposed to go in and out like that?

SR5_4WD · 04-25-2006, 02:39 PM

It must just be on the verge of completely not working. Once it stops working, it will stay on. The CEL in my car is on for the same reason, and I'm not looking forward to paying $200+ for a new one.

Patman525 · 04-25-2006, 11:07 PM

O2 sensors aren't $200, i got one for 20 bucks at advance auto, granted it's a universal and you have to plice the wires, that's not hard. even ones made for the car don't break $100, that i've seen.

SR5_4WD · 04-26-2006, 02:10 PM

OK I have had to replace my fair share of O2 sensors and here is what I have picked up.
-If you go to the dealer, you will pay 100$ more than needed.
-If you get a universal one you can get away with a lot less $ (like you said)
-But the one that I looked for, for near my cat costs the same at the Napa store (where they are cheaper) than the dealer. This I have looked around and that is the case. 200$ either way.
Now the front O2 sensor is different and is way cheaper if you know where to go.

Patman525 · 04-26-2006, 03:46 PM

yea i'm talkin the bank 1, sensor 1 O2 sensor. I didn't know the ones closer to the cat were more expensive. that sucks!

JohnO356 · 04-26-2006, 08:36 PM

Patman-- What code are you getting?

Patman525 · 04-26-2006, 11:11 PM

I'm actually not getting one, i was just saying that the bank 1 sensor 1 O2 sensors are like 20 bucks for the universal kind. only thing i've had a code for is for a misfire, so i changed the plugs (which were shot) and wires and it was a-ok. and that was a while ago.

JohnO356 · 04-27-2006, 07:05 AM

Sorry, meant to address the question to Shaun, the original poster.

shaun3701 · 04-27-2006, 11:26 AM

I don't know what the code was... the guy just told me it was the O2 sensor.

JohnO356 · 05-01-2006, 06:35 PM

Shaun-- If you haven't had the problem fixed yet, get the code to see if it's P0420.. A lot of mechanics will diagnose the P0420 code as the rear O2 sensor, and often times that's the problem, but with the light coming on for awhile, going out, back on, etc, it sounds more like the catalytic converter. When the O2 goes, it usually goes, period.

thespud · 05-01-2006, 08:57 PM

^^ Not always... my engine light troubles was an O2 sensor that was on the brink... Did exactly what he said it's doing.