Jap Imports

Hi All,

Putting a decat downpipe on my Impreza Bug Eye, Got the Lamba sensor on the Manifold , and a big hole where one should go on the downpipe. It has a small sensor on the orignal cat downpipe that does not fit my new pipe. Do i need this sensor or can i leave it off.

Its a Jap Import STI Bug eye

Butty

iTrader: (2)

Sounds like the EGT sensor to indicate the downpipe cat has overheated. As you haven't a cat any longer then it is redundant.
Removing this on a classic Impreza didn't cause a CEL error but not sure about the newage cars - you may end up putting a resistor across the connector.

Nick

Jap Imports

Thats what I thought,

Any other idea's?

welshwolf

Probably not the answer you are looking for but recently de-catted my STI 7 01 MY bug eye also jap import and there was only 1 lambda sensor although my 3" downpipe has 3 entries, 1 for original lambda, 1 extra fitted next to it to aid mappers to fit their lambda without removing yours(normal condition it is blanked off) and 1 at top (turbo end) which i am told is for UK sti. JDM is in up pipe but not seen myself. I also had to blank this one off.

Just some info for comparison.
Barry

Jap Imports

I think I'll fit the Pipe , and leave this other sensor off , Se what happens , Will the scoob need a remap after a full decat system

welshwolf

I don't pretend to be an expert but I did. My original plan was to de-cat and re-map but unfortunately my exhaust did not arrive by the time my appointement came around for re-map. Car was remapped without exhaust fitted but during mapping session my Fuel pump was starving the engine so he put a safe map until I changed my pump. Couple of weeks later by which time I fitted the de-cat exhaust and new fuel pump i returned to be re-mapped and the outcome is awsome to say the least. The car now just pulls so much better also much smoother however the 3" full de-cat system does drone a bit on the motorway but it's a second car for me so no problem. Would reccomend anyone to have it done. Also had re-map to ensure fuel is 98 not standard 100 ron as it is JDM.

So basically if you are adding de-cat then re-map is highly reccomended not only to ensure you get the best power delivery but more importantly to check it is running at its best as when i returned after fitting exhaust and fuel pump the engine was running very very rich which is a result i think of fitting new fuel pump.

Midlife......

iTrader: (2)

AFAIK the Bugeye has three sensors in all. The one in the up-pipe is the EGT sensor.

The bigger sensor in the downpipe is the Lambda sensor and the smaller one is an 02 sensor to detect the efficiency of the cats. Leaving off the small sensor will give a steady CEL P0420 (cat below efficiency) eventually.

The CEL can be got round by a CEL fix or by an ECuTeK remap.

That's my understanding of the situation. Someone on Cumbrianscoobs posted a real neat schematic of the bugeye engine and associated bits but can't find it at the mo. I'll look later.

Shaun

scooby_mania_yeah

I have a Bugeye (Y Reg) 2001, Recently had a Downpipe fitted but There is only 1 sensor and thats the Big one (Lamba Sensor).. How come i aint got a 02 sensor on mY CAR...... Does anyone know ??

Butty

iTrader: (2)

A lambda sensor is also known as an O2 sensor.
Sounds like you may have a car originally for the Japanese market then.
UK newage cars have O2 sensors in the drivers side exhaust headers and the small centre section with an EGT sensor in the up-pipe.

NIck