A basic emissions check, prior to the annual test
On a vehicle which has passed all of the required criteria, steering, brakes, electrics and then fails on just the emissions, can be a problem and inconvenience especially on these cars, when this could have been rectified before hand with a basic emissions check before the full test, most of the smaller type garages will offer to do a basic emissions test with no charge, or maybe for just a couple of quid.
Our own procedure before taking the pre-booked annual test, is to add some fuel additive, take a good long drive to achieve the vehicles full operating and running temperatures, then arriving at the test station minutes before our appointment, confident that the emissions test done a few days earlier should not now be too much of a concern.
Taking into account, that not all emissions tests are going to be successful, a short and direct drive to the testing station is one of them, The engine maybe warm to hot, but it wont be at its fully working and operating temperature.
The emissions test, which is generally carried out after all other vehicle checks have been completed during the annual test, and not when you first arrive. This may show if the car is in a genuine and tip top condition, and has not just been 'thrashed' just to get it through the emissions. Not all of our tests have run so smooth, in 2014 it struggled very slightly on emissions.
Our own problem was being too over confident on previous tests, and just driving direct to the testing station a mile or so down the road, not such a really good idea, Shown below, dashcam capture of a 2003 Rover 25 during one of the MG's warm up runs, prior to the MOT test.
Rover 200/MG-ZR Technical and Information Pages (c) 2004-2018.