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Anybody know approximately how much a shop would charge to sync cam and crank position sensors?
 

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You don't sync those sensors, those sensors are there to sync the electronic engine management to the engine, the electronic engine management syncs itself. The engine is synched mechanically. So if you have something out of sync, at least bad enough that it is noticeable, it has to be a mechanical failure in the engine.

Of course a sensor going bad or a malfunction may give you the impression something is out of sync.

Everything is synced off the Crank Position Sensor, but the Crank makes 2 rotations before you go through all 4 cycles of a 4 cycle engine. So how does the engine computer know if the cylinder that is going to fire the spark plug, if its on its compression stroke or exhaust stroke, or to open the fuel injector, is it on its intake stroke of its power stroke? The Cam only makes 1 rotation per every 2 Crank rotations, so their is a Cam Position Sensor that just tells the engine computer which of the 2 rotations the Crank is on, so the engine computer can sync itself.

A bad Crank Position Sensor (CPS) and the motor won't run, it doesn't know when to fire the spark plugs or fuel injectors.

But a bad Cam Position Sensor, depending on the motor, it may run it may NOT. Many motors have wasted spark ignitions, that fire the plugs on every rotation, so the syncing of the engine computer is just for the injectors. No signal from the Cam Position Sensor, the engine computer will guess and it has a 50/50 shot. If it guesses right, the motor runs fine, if it guesses wrong, the motor may run, but the injectors are opening at the wrong time and its running of fuel pooled in the intake, so it runs crappy, until you shut it off and start again.

A good place to start is to check the stored Diagnostic Trouble Codes, you can do a youtube search to watch a quick video on how to do the "key dance" to get the instrument vehicle information center (EVIC) to read out the stored codes.
 
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