MOT failed on emissions

Hi, just a quick question...
My mother in law's freelander (1.8 petrol) has just failed its MOT on emissions. Its a shed and there looking to upgrade but they wanted to get it through this MOT first. Just wondered if anyone has any suggestions on a quick and cheap fix. (think i'm being hopeful but thought i'd ask befor it goes scrap yard). A mate suggested redex fuel additive but whats the changes of this working? is it likely to be the CAT gone or could other things cause this? any advice or suggestions would be great? thanks, Chris.

Some people have had success with fuel additives, I would start off by making sure the spark plugs are in good condition and that the air filter is clean, you might have to replace either the cat or the oxygen sensor though. Make sure its fully warmed up before the test and give it a good thrashing to clean it out.

Change the engine oil and filter if its not been done in the last 6 months !

Usually when cars fail on emissions all you need to do is give it a good old frash round the block, usually clears ****e and the re-test passed with no problems.

give it a go, worked for me.

mine just needed a new rear silencer to pass last year, i fitted a new manifold this year with the cat in , and this year the emmissions were mighty low.