does my 91 325 touring have a cat

[gorgeee]

hi my touring had a charcoal canister in the engine and so i was wondering if it has a cat.i've had a look but cant tell and some people have told me the 325i's that have a cat, have it in the silencer so can be harder to tell?
if it has a cat and i want to remove it and fit a complete system will i need to make any other mods to say the fueling?
any ideas ?

[Brianmoooore]

The connector for the lambda sensor is fitted on all late models, cat fitted or not, and is clipped under the battery tray.
If you have a plug connected into this socket, and if you have three relays fitted under the plastic cover on the left hand inner wing, then you have a cat fitted.
I'm not sure if the ECU would get upset or no by the removal of the lambda sensor. Easiest thing would be to replace the ECU with one from a non cat car.

[jmc330i]

If you do have a Cat fitted on a 1991 325i then it can be removed with no worries.
The Lambda sensor can be left in place, it will do no harm without a Cat but the sensor will still be needed for the engine to run correctly.

If you remove the Lambda sensor then the ECU will go into a 'limp' mode as it is not getting the feedback signals that are needed.

[Jhonno]

try putting a mouse infront of it see what happens..




No? ok then *gets coat*

[fastcarz464]

Good one Jhonno!

[Danstable]

My 91 Touring does have a Cat, been told so by the garage, and have seen the Lambda sensor in the downpipe.......I think! My plan is to get a threaded collar welded into my new exhaust and just leave the Lambda in place. I've been advised on here to do that or change the ECU and remove the Lambda sensor.

[Brianmoooore]

M18 X1.5 is the nut you need for a lambda sensor. Weld it into the innermost downpipe just in front of where it passes the control arm bush. Monitoring the exhaust from just three cylinders works OK.
( I have fitted lambda sensors to a few exhausts that didn't have one. Needed fof LPG conversion ).

[gorgeee]

thanks alot guys

[jmc330i]

My plan is to get a threaded collar welded into my new exhaust and just leave the Lambda in place.

Yeah, just do that. It will be fine.

try putting a mouse infront of it see what happens..

No? ok then *gets coat*