So Monday arrived and the old girl failed on the reasons below:
Repair immediately (major defects):
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Exhaust Lambda reading after 2nd fast idle outside specified limits (8.2.1.2 (c))
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It's the last one that concerns me most he mentioned the butterfly in the backbox being seized would this make any difference at all ?
Do i just get it back change the exhaust, the cat and 2 lambda sensors and hope that that does it ?
The valve thingy on the RHS tailpipe on mine seized up, although it passed an MOT like this. I freed mine up with some Plus Gas and a bit of working with a spanner. It freed up nicely but I'm not convinced it worked properly. I would at least ensure that it is open.
The classic way of optimising the exhaust emissions is to get the catalytic converter hot by giving the car a good thrashing immediately before the test.
Could it be old petrol in the tank causing the problem?
Others will probably have more useful advice but my MOT man usually needs to check it a couple of times to get a satisfactory reading.