Car Doctor Q&A: The Car Doctor has a Hunch!

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Car Doctor John Paul is full of advice this week, including diagnosing a rough idle and multiple ways a plunger can fix your car.

Q. I just purchased a Honda Pilot with 300,000 miles on it. I have been told all the regular maintenance work has been done, if fact the timing belt was replaced in the last month. The engine runs good and drives down the road well but the engine vibrates at an idle. There isn’t any check engine lights on and according to the local auto parts store there are no codes stored. I know the car has lots of miles do you think it is something serious? The one thing that a friend of mine did check he put a vacuum gauge on the engine and the vacuum reading was a bit low and the needle was bouncing around quite a bit.

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A. I would start with a compression test just to check the integrity of the engine but I have a hunch that the problem could be caused by a poorly installed timing belt. If the belt were installed and not lined up exactly with the proper timing belt marks, that could explain the rough idle and low vacuum readings.

Cheapskate Challenge: Using a plunger to fix your car.

A plumbers plunger can be used to pull out a dent in a panel providing the metal isn’t creased. A little grease applied to the lip of the plunger can add suction allowing more force to be applied, heating the panel with how water or a heat gun can help too. The handle can be used to hear and feel vibration from a faulty bearing in a water pump or alternator or even help determine where a engine noise is coming from. Unscrew the handle from the plunger and hold it up to your ear and hold the other end on the suspected component. If a bearing is noisy the sound will travel up the handle allowing you to pinpoint the noise.