On my decat pipe there is an oxygen sensor. But the nut holding it in is snapped. So removal would be hard. Do you need to connect it if you dont have a cat. Will the ECU warning light come on if its not connected?

A bloke I know said to unplug it because if I dont ill get the cat light coming on all the time, and he said I didnt need to connect it.

Any views appreciated,
Regards Ronnie

 

The check engine light will come on at some point, and depending on your base fuel map and breathing modifications, the car will run too lean or too rich at idle and cruise. So economy may suffer, emissions definitely will (you will fail an MOT even with a cat in).

 

Cheers
How do you get the sensors out without damaging them!!
Im thinking of getting a magnex downpipe. Will it come with a sensor, or do you think ill have to use my sensor out original cat pipe?

Thanks Again
Ronnie

 

what age is the car? Older cars (pre 97 wrx I think) have the O2 sensor in the exhaust manifold under the front right corner of the car. (The thing in the downpipe is a heat sensor in this case, and is not necessary in a catless system)

On newer cars, the O2 sensor is in the downpipe. As John says is very necessary (in all cases).

This confused me at first, as my car was built right on the MY96/97 changeover, and seems to have bits from both sorts...

 

Its not an 02 sensor, it is an exhaust gas temp proble and is used to light the 'cat on fire' symbol on the dash.

Unplug it from the loom as if you have de-catted its not required.

have you got it to fit now?

simon

edited as I can't spell

[Edited by RRH - 11/25/2002 8:02:35 AM]

 

Sorry for taking so long to reply!!!
No its still not fitted, i think ill scrap it and buy a magnex!
Anyone know where the cheepest place to buy them is?
And in response to the other threads its a 1994 WRX and the guy who commented on the sensor said it would get top warm and the light on the dash to warn this for the cat would come on. I asumed it was the oxygen sensor!! its on the downpipe I think near the bend!!!
Cheers
Ronnie

 

Definatley your cat temp sensor m8.
Disconnect it at the clear / white 2 pin connector on the drivers side of the engine bay (beside the boost soleniod)

Pete