Q: Car Sputtering at Hwy Speeds

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My van has a very intermittent sputter at highway speeds. (Feels like it's running out of gas.) It typically happens between 40-70 mph with no engine light. But is not consistent enough to create. If I cruise at say 65 mph it will not happen even when going up and down a hill, however it occurs when I am accelerating up to that speed. It does not make difference of I accelerate fast or gradually. I have changed the spark plugs and wires and have tried a fuel treatment. Other then this issue the vehicle runs excellent and has been perfectly maintained. Internet research has suggested the cam shaft synchronizer assembly. I didn't know if that sounded accurate.

My car has 200000 miles.
My car has an automatic transmission.

There are several things that can cause this kind of sputtering to happen, however one that is very common is in fact the camshaft position sensor failing which can cause problems with ignition timing resulting in sputtering as you describe as well as many other problems. As you may know, the camshaft position sensor is a magnetic sensor that monitors camshaft speed to regulate ignition timing and fuel injection timing. It gathers and sends information about the car’s camshaft speed (and as a result the position of each piston) to the car’s electronic control module. This information is received by the computer, which then uses this data to further calculate the time of ignition and the timing of fuel injection required by the engine. When this is not working properly, you may experience a drop in power, poor idling, poor fuel mileage and problems starting the vehicle. As the sensor begins to fail and gets worse over time, the signal it provides to the computer weakens as well. I would recommend having a professional from YourMechanic come to your location to diagnose your camshaft position sensor.

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