De cat pipe

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D2LTA
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Post Wed Jul 06, 2005 9:09 am

Not long 'till i pick up my touring and have sourced a non cat pipe for it.
As it is a catalyst model will this effect it, i remember my wife having problems with the lambda sensor on her ti compact.
Does anyone know if an e30 316i (93 model) has the sensor and will it be possible to fit the non cat pipe and run it without any 'hiccups'????

:skip:
316i touring lux
Lancia integrale
Reebok Classic
Marks & Spencers Slippers
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Brianmoooore
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Post Wed Jul 06, 2005 9:33 am

Assuming you are in the UK, a 93 model will almost certainly have a cat.
If it was first registered after August 92, then you will have problems getting this car through an MOT with the cat removed, unless you do a LPG conversion.
If you want to run it without the lambda sensor, then you will need to change the ECU for non cat one, or fit a lambda simulator (square wave generator), as the original ECU will get upset without the lambda signal.
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D2LTA
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Post Wed Jul 06, 2005 4:57 pm

Unless I can source a Lambda simulator i think i'd be better off buying the exhaust with the cat. I was hoping i might gain a few bhp and save a few pennies by not fitting a cat pipe.
I don't think the MOT would be a problem :wink:
jmc330i
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Post Wed Jul 06, 2005 5:19 pm

You dont need to remove the Lambda sensor to remove the Cat. They arent linked as such.
The Lambda just monitors the exhaust gas to keep the fuel mixture at a preset value, richening or leaning the mixture as is required. If the car is Cat equiped, the Lambda sort of protects the Cat cause unburnt fuel etc damages part of the Cat ( I think the chemical coating on the honeycomb part and so the Cat stops working ).

You can run a car without a Cat with a Lambda sensor, but not the other way round.

Just run it as it is with the Lambda all hooked up, but without the Cat.
James
'91 325i Sport
'93 318i touring 16v
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D2LTA
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Post Thu Jul 07, 2005 6:18 am

Thanks JMC, I'll fit the non cat pipe and see what happens.... If it plays funny bu**ers then i'll weld the old cat onto the new pipe.

:lol: