Edmunds Answers

Voted Best Answer

  • avatar karjunkie 12/21/08 10:20 am PST

    It is most likely a bad crankshaft position (CPS) sensor. It is a cheap and easy fix as it just bolts on the intake side of the engine case with one 10mm metric bolt and it has an electrical connector that just snaps on to the wiring harness. The CPS sensor often causes the symptoms you describe. There are several other things to check for a stalling/no start problem. I would change the spark plugs, fuel filter and the air filter. Make sure your injectors are clean and functioning properly. Run some Techron Concentrate injector cleaner through a couple of tanks of gasoline. Lastly, clean the MAF sensor wires in the intake plenum with CRC sensor spray. All these steps are easy and cheap to do and are advisable anyway since they are maintenance items.

    In terms of finding a good local mechanic, I would go to Car Talk’s Mechanics Files site at:
    http://www.cartalk.com/content/mechx/fi
    nd.html


    Enter your zip code and you will get a list of mechanics in your area that other consumers have used and highly recommend. Look for ones that specialize either in the make of your car or the type of repair you need. Call 2-3 of them and ask for a ballpark figure on the repair. I have personally used this site with great success to find good honest mechanics and can highly recommend it. Good luck!

Answers

  • karjunkie 12/21/08 10:20 am PST

    It is most likely a bad crankshaft position (CPS) sensor. It is a cheap and easy fix as it just bolts on the intake side of the engine case with one 10mm metric bolt and it has an electrical connector that just snaps on to the wiring harness. The CPS sensor often causes the symptoms you describe. There are several other things to check for a stalling/no start problem. I would change the spark plugs, fuel filter and the air filter. Make sure your injectors are clean and functioning properly. Run some Techron Concentrate injector cleaner through a couple of tanks of gasoline. Lastly, clean the MAF sensor wires in the intake plenum with CRC sensor spray. All these steps are easy and cheap to do and are advisable anyway since they are maintenance items.

    In terms of finding a good local mechanic, I would go to Car Talk’s Mechanics Files site at:
    http://www.cartalk.com/content/mechx/fi
    nd.html


    Enter your zip code and you will get a list of mechanics in your area that other consumers have used and highly recommend. Look for ones that specialize either in the make of your car or the type of repair you need. Call 2-3 of them and ask for a ballpark figure on the repair. I have personally used this site with great success to find good honest mechanics and can highly recommend it. Good luck!

  • MrShift@Edmunds 12/21/08 12:21 pm PST

    Could be lots of things.

    Try this. When it won't start, floor the gas pedal and keep it floored. If the car starts up (perhaps a little reluctantly) then it's been flooded with gas while it sat, perhaps by a leaking injector. Naturally, after the car starts up, you let your foot off the gas. Don't race the engine.

    Other than that, if that doesn't work, you might have a mechanic test the fuel pressure in the fuel rail at the time it won't start. Perhaps your fuel pressure is bleeding off during the day and this contributes to the hard start.

    If that doesn't work, have the mechanic test for spark during the non-start. Maybe a heat-sensitive ignition module or a bad crankshaft positioning sensor?

    Sounds like everyone's been guessing and nobody's measuring anything.

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