Hey guys

I recently installed a set of megan headers, the prob is in the process i screwed the tread of my sensor.

So i went to an auto shop cause the toyata dealer here doesnt have them
I wento the shop and they gave me a sensor and told me it would work...i looked at it and it was denso....he told to know if its compatible with your car you have to look at the color of the wires wich for a scion is 1 blue 1 white and 2 black. I want to know is this true????.....I installed it already but i get a check engine light wich is probably caused by my new headers wich is why i dont know if its working.

tnx in advance

 

Every header causes a check engine light, but it's not from the header O2 sensor. It's from the S-pipe O2 sensor. You'll need to do the anti-fouler technique, or get an O2 simulator from one of the companies out there that makes it.

If you take it down to Auto Zone or some other parts store, they'll probably be able to pull the OBD code and let you know what it is. But it's probably a malfunctioning cat code...

 

yeah i know i did the antifouler thing today but it didnt work.
Do you know if what the saleman told me about the 02 sensor wires is true...cause i screwed the old header sensor.

 

The damaged sensor from your header is called an "Air/Fuel Ratio" (AFR) sensor. It's a wideband sensor which is different from the "Heated Oxygen Sensor" on the S-pipe, and also has a different Toyota part number.

All the heated O2 sensor in the S-pipe does is monitor the efficiency of the catalytic converter in the stock exhaust manifold. That's why when you install an aftermarket header you have to do the anti-fouler trick because that cat is gone.

The AFR however is a major input to the ECU in controlling engine combustion. I don't know of any non-Toyota substitute for the AFR and even if I did I wouldn't use it.

Try another dealer in your area, or search online for it. I would ONLY put in a genuine Toyota AFR, even though it's going to cost you over $200.

 

Nah i dont think the tc comes with wideband its probably narrowband man.

 

Well you don't think it comes with a wide band, but it does... the one on the manifold, thats why its a 220$ dollar sensor, the second one in the S pipe is a 4 wire narrow band.

and as far as i know there is no substitute for it(one in header), other wide bands don't work as a replacement.

 

Well i purchased another denso sensor and it seems to be working fine

 

The sensor that orginally came on my scion was also 4 wires.

1 blue 1 white and 2 black

 

There are 2 sensors on the TC "2" the second one is just a 4 wire narrow band I'm sure you can find a denso replacement since toyo uses denso parts to begin with, the first of the "2" sensors is a 4 wire "wideband" air fuel sensor that puts out a diff current read out than most aftermarket wide bands. it depends on which of the "2" sensors you are talking about replacing...

 

Well i replaced the first one(headers) cause the tread was damaged on it......the prob is that toyota doesnt supply scion parts here. So i had to buy an aftermarket sensor to replace the first one. It just happened to be denso

 

the AFR sensor is a wideband sensor

but here might be your problem... after doing the install, and the anti-fouler, did you disconnect your battery to reset your ecu?

 

Well i replaced the first one(headers) cause the tread was damaged on it......the prob is that toyota doesnt supply scion parts here. So i had to buy an aftermarket sensor to replace the first one. It just happened to be denso

 

your local dealership might not keep it stocked, but they can order it and get the part in a day or so.

but like i said, did u disconnect ur battery to reset ur ecu?

 

Well this will sound stupid....but they look the same.....the only difference i could see from the original a/f sensor and the other on e i bought is that the tip on the new one has more holes in it

 

 

yup i did

 

Ok well then whats the verdict? no more CEL? alls well?

if you get the CEL back which you prob will, then you know that you have to use toyo's official wide band.

good luck!

 

the antifouler doesn't always work. put a toyta AFR sensor on it and get a o2 sim.

 

i was able to get a second hand one
is it true that people with megan headers need to use a 3 fouler setup?
i have 2 on mine and still getting the cell

 

The number of holes might matter or it might not, what's important is the voltage output of the AFR to the ECU. This will affect your performance and fuel economy even if you don't have a CEL.

Don't know how much further you want to take this, but if you or anyone else are interested here's how to ohmmeter check the AFR and the HOS: (resistance is rated at 68 degrees F so test them at the coolest time of day)

https://www.scionlife.com/tech/manual/?manual=tc05_1348

Be interested to see how your Denso meters out in comparison ...

Also if you post up the part number of your Denso maybe someone could research it and see if it crosses to the Toyota part number. It probably won't but if this in any way leads to finding a suitable sub for the AFR that's well under $200, there's still a lot of future header installers/AFR strippers out there that might benefit.