UK Car Repair: Corsa, High Emissions, mass air flow meter, mass air flow sensor

Question
QUESTION: Hi, I had an MOT on my 1998 1.2 Corsa and it failed on all the emmisions out of range, also it doesn't run very well, it misfires and sometimes wont start without revs when warm. i have replaced the lambda sensor and spark plugs but its no better, any ideas thanks

ANSWER: You need to have it scanned for fault codes, there can be many reaons for these types of problems,  What were the emmission readings?

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QUESTION: There were no fault codes, the CO were 9.00% HC were 750 and Lambda to Low

ANSWER: It is running very rich, I would suspect the Mass Air Flow sensor.

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QUESTION: There is no mass air flow meter on the vehicle, it is single point injection,

Answer
What does it have to monitor the air intake? There would usually be some kind of unit between the air filter and the throttle body, is there not? The car is running very rich, too much fuel or not enough air! It would be a good idea to do a fuel pressure test, the pressure may just be way to high.