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1998 buick park ave 3800

this car runs great,but stalls for no reason every few days,then it starts right up.i once had a check engine light on and had it checked,they said it was the cam sensor,im not sure thats the problem.and i cant locate it easely.is it behind the harmonic balancer?or should i try something else?I had them shut off the check engin light so im afraid no mechanic will give me a proper diagnosis.please help with any answers.the care has 78,00 miles

The problem you describe with your 3.8l Park Avenue is the same as my Bonneville. It?s either the cam or crank sensor located behind the harmonic balancer. The sensors are cheap (around $25-30 each). To get at the sensors, you need a special puller and an air wrench to get the harmonic balancer off. My mechanic put the car up on his hoist to remove the balancer. I can?t imagine getting the balancer off while lying under the car. Replace both sensors. The labor cost is in removing the harmonic balancer. You don?t want to do it twice if the other sensor fails. While you?re at it, have your mechanic check the condition of the balancer?s rubber seal. If it?s going bad, you should replace the balancer as well. The seal should be good at your mileage. When the balancer goes bad, you?ll hear a horrible clanking sound when you start the car up. And I do mean horrible.

There may be a problem with the camshaft position sensor, but that won’t cause the engine to stall. The camshaft position sensor determines when the fuel injectors should fire. If the cam position sensor fails, the computer goes to a default value to fire the injectors or a limp mode so the vehicle can still be driven. The problem you’re describing points more to either a faulty ignition module or a faulty crankshaft position sensor which would cause the engine to stall.

Tester

Do you have the actual error code like: P0123?

Th is what the camshaft position sensor looks like: http://www.autozone.com/R,2315559/vehicleId,2380301/initialAction,partProductDetail/store,1140/partType,00111/shopping/partProductDetail.htm

no error code.we drove it all day on and off today and it ran fine.then we got in to start it and it didnt start after 15 miniutes it did.runs great and no error codes.

thanks I guess at this point I’ll go to the dealer.I’ll let you all no what happend