Hi
I have a Jap Import WRX Turbo 1994 Impreza, It has a straight through exhaust on it including a de-cat downpipe. I have noticed that the downpipe has a bung in it where the Lambda sensor should go, So at the moment it hasnt got the Lambda sensor in the downpipe. Would this affect the MPG and the way it runs?

As far as I'm aware it is running the standard ECU/Injectors and Turbo etc.

Thanks for your time

 

I think you'll find that is for an optional aftermarket wideband lambda sensor that you can attach a gauge to e.g. to make sure it is not running lean during boost or for tuning.

Is it near the turbo like this Cobb one ?
http://finelineimports.net/images/_cobb_downpipe3.jpg

 

You car doesnt have the Lambda sensor there. Its located in the header close to the drivers side front wheel well area.
If you had a std exhaust system you would have a CAT on fire sensor somewhere around there though.

The boss is for later cars, they have the sensor in the downpipe just after the turbo.

 

No, The bung on my downpipe is further down near the footwell but still in the downpipe. Should I be running a Sensor there as I have found the wiring for where the sensor plugs into.

Cheers for your help

 

Then it is indeed the one that detects issues with the CAT as mentioned by 172Sport. These are often deleted with no issues.