anyone help plz

[sophie23_98]

just had the mot test done it passed everything apart from the immsions the co test read 5.4 and the lander sensor was 1.4 he told us to go for a good ride in it so we did, came back tried it again and co test read 0.19 so that was fine but 1.4 on the lander it needs to be 1.03 or something like that so he did the computer reading on it and the co test came out at 4.8, i am fed up with it he mentioned that the lander sensor on it might be nackered but had a word with pip and he thinks it could be fuel in oil or air pump not running correctly but i need to sort this out before tuesday as the sva test is then anyone shed any light as to what it could be, there is a massive exshaust on it the mot station thinks it could be drawing air into it