About to do my decat up-pipe 2morow - with this post cat sensor - do I put it back or leave it off - what do you do with it and what are the implications????
advice??

 

is the the downpipe your de-catting or the up pipe off the headers??

 

Hi - its the down pipe - on an MY95 classic import WRX

 

Because your new downpipe hasn't got a cat in it, then there's nothing for the EGT sensor to measure anymore - it's redundant!

Just leave it soemwhere safe in the engine bay... cable-tie it away from any potential moving/hot parts.

 

don't worry about it , no cat then there is no way it can overheat (think mine was blanked off)

 

How many times have we posted in the same minute, mbwrx?!...... Er, about 3.

 

Thanks guys - been having a bit of a fret over it.
Just to ask also - if I put the sensor in the hole provided - will that cause probs or???

 

Bump

 

no, just leave it in the hole

 

HI sorry to hi-jack thread!!! i've an 53 wrx and want to fit a decat downpipe from the turbo, is this cat heat sensor the one in the middle of the small 'box? i thought it was a down stream lambda sensor? do i have a down stream lambda sensor or can i just de cat and no warning lights will come on? thanks

 

Unfortunately for Newage cars you need CEL fix or a remap iirc to stop any warning lights

 

The Newage does not have a "cat on fire" sensor....it has a lambda sensor in the downpipe which checks for the efficiency of the catalytic converter.

If you remove the cat then the ECU thinks it's not working and throws up CEL P0420 indicating you have a cat / emissions problem. The CEL has no effect on performance, the most effective way is to have the car re-mapped (about £600) which will remove the CEL and free up a significant number of BHP

The alternative is a CEL Fix which sits between the sensor and the ECU sending signals to the ECU to fool it into thinking a cat is still there.....not always 100% effective though as the ECU expects a fluctuating signal.

HTH

Shaun

 

would it matter if the cat was removed and the cel was on but left? would it loose power or ok to ignore?

 

Nothing happens apart from the ECU lighting the CEL and storing code P0420. There is no loss of power as the ECU does not see this as a danger to the engine.

The main problem is that you won't know if the ECU has detected anything else as the CEL is lit...........and the light is very annoying !! especially at night ....

Shaun

PS it's also a dead give away at MOT time LOL

 

Right - just picked up the scoob and De-cat downpipe now fitted - Its appears that there was only one sensor on the original pipe going into the bottom of the cat (presumably the afore mentioned "cat on fire" sensor. This has been disaconnected and left off completely.
The two sensor holes in the decat pipe have been bunged up tight with the bols that came with it.
Only driven about 5 miles home but the car seems to boost better to 1 bar and theres quite a hiss from the turbo.
Seems all good so far!!
My only question now is - Where the hells the 02 (lambda) sensor???????

 

what you mean. is it missing??? or just no where for it to go

 

quick question if you dont mind me hijacking. is there a sensor on the uppipe?? as im fitting my headers tomorrow and would like to know before hand. my headers have the hole but do i need to refit if there is one. 97 sti

 

There was just no other sensor on the original down pipe so I assume the lambda sensor must be on the engine side of the turbo somewhere???
Its could be that yours is like mine maybe and the 02 is located forwrd of the turbo somewhere????
Lots of somewheres???? hahahaha!

 

scooby72, your MY93-96 "phase 1" car's Lambda is in the driver side header elbow section. Take a look underneath and you'll see it protruding out beyond said elbow's heatshield...

 

Joz - your a star m8 - Iknew Id seen the little bugger when I rebuild the front afrter my Deer incident - Thank you bud!!
So basicly all should be fine and dandy!!!
Has anyone got a pic of a chopped heatshield - loooks pretty straight forward but always good to have 2nd opinion!!!
Dont want much do I....hahahahaha!!!!!!!

 

Here's my newage WRX exhaust diagram

http://i77.photobucket.com/albums/j5...st-diagram.jpg

Shaun