Are decat pipes legal? I bought a Subaru and from a dealership and had several problems with it with an ECU light coming on all the time.

I got in contact with the previous owner and she said that the ECU light had always been on due to having a decat pipe fitted.

Could this be the case? Also could the garage sell it to me if it isn't legal?

 

A decat pipe will cause the ECU or EML (engine management light) to come on. What year is your car? If you have a classic you can read the ECU codes yourself, if not you will need to buy a reader.

Decat pipes are not legal because the cause the car to fail its emissions test, but no one goes round checking if you have one fitted or not so I wouldn't worry. All of my previous cars have had decats.

Either a friendly mot shop needs to be found come mot time or the original cat will need to go back on to pass.

 

if you speak to the delaer they should supply you with a cat to fit as they sold you a non road worthy car... then as said, if you cant find a friendly MOT tester, stick it on for the mot

 

A car with no catalytic convertor isn't legal to run on the roads. But your not likely to have any problems until mot time unless. Infact for post 2001 cars "most" sports cat's are not road legal either.

For Mot there are places that for a fee will fit an exhaust with cats and Mot then refit yours after. I was quoted £100 labour/loan for this + mot.

The code is easy to map out or the ecu can be fooled with a resistor. Even with the resistor mod the CEL light will come on in a wrx when giving it the beans due to the EGT sensor getting hot . Known as "cat on fire" .

Again this can be mapped out. Ive removed the second lambda and the EGT and just turned them of in the ecu.

 

Well I've just been to an exhaust centre to get them to check it as I'm not sure what I was looking for. But both cats were there. So if there is an air leak in the system which they said to me is the fault and they've changed the lambda sensors etc what else could it be?

A hole in a pipe somewhere? ECU is faulty as its reading a problem? Engine is knackered- only done 51,000 and is a 54 plate