Question about 1999 Volkswagen Passat

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Vaccuum under the air filter box runs even when the key isnt in

There is a 3/4 in hose going form the air filter box down to something underneath of it. It is some sorrt of vaccuum, that vaccuum runs even when the key isnt in the ignition, draining the battery. Jumped it to get it started and then it would surge at 1500 rpms and had hardly any power. Took it to a vw mechanic who charged a lot of money and said they fixed it. A week later It is still doing it and now when i try to jump start it, it will turn over, but it wont start.

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It sounds like your air pump is malfunctioning. It is used to pump emissions out the back of the car. it is controlled by a vacuum. These will drain your battery if the vacuum does not send a signal to shut it off.

Posted on Jan 01, 2009


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Car will start but stalls imediately after & wont stay running

You can have one of several issues that can't be determined without a fault code reader to narrow it down. Typically, it sounds like you have a fuel supply related issue, but it could easily be something else like an unplugged vaccuum line, or faulty EGR. It is best you buy an inexpensive fault code reader and a Haynes Manual for your car... look up the codes in the chapter on Emission Controls and get back with us for assistance. A vacuum line diagram is located under the hood, go over every lie carefully and look for cracks and leaks, check the air filter box and any larger hoses carefully for cracks. You can do this easily, be patient and do a thorough job of it. Pull out a single spark plug and look at it for excessive carbon deposits. Replace with DENSO Iridium plugs that last 60K miles. Look at you spark plug wires... you will need an inexpensive multimeter to check them; Radioshack has them for cheap.

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Hi, my 2002 malibu hesitate and whistle when I accelerate. It only works fine under 20mph, but when it exceed, it whistles and hesitate on accelerating. On highway, it barely goes up to 60mph and when...

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I have changed everything under the hood, maf sensor, coil packs, spark plgs, egr valve, h2o sensors, fuel filter and still have a miss. When I changed the fuel filter I found lots of sand in the filter,...

as long as the sand was caught in the filter, and u replaced the shouldn't. it could be something as small as a collapsed or dry-rotted vaccuum hose, or as big as a bad head gasket. I would run down all of my vaccuum lines and check them first, and if they all are ok, i would take it in and have a compression test done.

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This might be as simple as checking for vaccuum leaks in th e air hoses, sounds to me like when the revs drop the vaccuum stalls the car. However, could b thee resistor in the distributer. Check timing, there could be a number of reasons, low fuel pressure, plug gap, point gap, blocked fuel filter, idle stop solonoid on carby. Hope this helps, check those vaccuum lines. Good luck

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