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1997 Nissan Pathfinder - Is there something I can do to improve the chances of passing the smog check?

I have an old car, it is a nissan pathfinder 1997. Will it help if I do some maintenance work before having the smog check done?
Answer:

You might want to do a general tune-up. Change the spark plugs and engine oil. You also want to make sure there are no disconnected, loose or brittle vacuum lines. A common fault of older vehicles failing the smog check is broken or disconnected vacuum lines. Vacuum lines are usually thin and exposed to high temperatures in the engine compartment. Soon as one is dislodged or broken, unmetered air enters the intake manifold, disrupting the air/fuel mixture. So just take a quick look under the hood. Make sure everything looks intact... and do the tune up. Have the gas tank fuel 3/4 of fresh fuel (manufacturer recommend octane), and ensure your Nissan is properly warmed up before the smog check. posted by SmogTips Support

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