How to pass an emissions test

Has that MOT vehicle licence renewal notice got you sweating? Bringing back memories of those pop quizzes in Grade 10 geography? With a little prep and almost no studying, your chariot should ace an emission test with flying colours. Here’s how:

1. Check engine light on means do not pass go. An Ontario emissions test station will not even start the test on a vehicle with a check engine light on or if the check engine light is inoperative (it has to momentarily light up when starting the vehicle). This means getting a scan done by a qualified technician and completing any necessary repairs.

2. New oil and filter for a fresh tailpipe sniff. If your vehicle just had a routine oil change or isn’t less than 25 per cent away from its next one, having this service done just for the sake of an emission test isn’t worth it. But if you’re close to needing one, and if the oil hasn’t been changed over the winter, getting it replaced is a wise idea.

3. Breathe easy before the test. A new air filter not only pays off in improving your chances at a clean e-test, but it improves fuel mileage as well. Even on the most technologically advanced vehicles, checking your air filter can be a do-it-yourself affair. If it’s a flexible type, give it a bend to see how much grit and grime are trapped deep in the folds of the filtrate material. Any dark brown or black discoloration or excess dirt means it’s time for a new one.

4. Put some spark back into your engine. Incomplete combustion is one of the main causes for e-test failures, and spark plugs are key to burning gasoline well. Check your owner’s manual to see what type of plug your vehicle is equipped with. Normal copper core units seldom stay efficient past 35,000 to 40,000 km and many car makers will call for their replacement much earlier. Platinum-tipped or long-life spark plugs are usually rated for 100,000 km, but if you’ve had any incidences of a rough running engine, or if the plugs haven’t been removed for inspection in the last 50,000 km, then have them checked before the e-test.

5. Leave the additives alone. Good fuel from a high volume retailer will go a much longer way to keeping your emissions’ stats in line than off-the-shelf chemical cures. Don’t overfill the tank before the test, this runs the risk of overtaxing the vapour control system and causing the release of raw gasoline fumes.

6. Sealed to perfection. Check the fuel filler neck where the gas cap seals onto it for any signs of rust. A quick wipe with some steel wool should suffice. Carefully examine the synthetic rubber o-ring on the cap looking for any tears or cracks. If this seal isn’t perfect, you may fail the test.

Brian Turner is an automotive parts and service manager with more than 30 years experience.

Photograph by: Gavin Young, Calgary Herald