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Before you post a question about why your car is broken for some reason, please read the sticky threads and the FAQ. They cover many of the common problems and solutions found with the j-bodies of this vintage.

**edit: There are now plenty of diagrams on this page so please use them.**

I am writing this little explanation to help those of you who have cars that won?t start for one reason or another. Hopefully this thread will help some people so the same questions don't have to be answered over and over again in the repair forum. I will try to write this as coherently as possible, but there are no promises.

First off, there are some simple things that should be checked before going any further. First, see if there is gas in the tank. There have been a few times where this was the only problem and this will prevent embarrassment and/or frustration later on down the road. Next check all of your fuses. Finally, if you turn the key to the "on" position and the check engine light comes on, then you have power to the ECU. (that?s a good thing! :wink: )

Once you confirm that there is power to the ECU check the ECU for codes. Look in the How-To section for instructions on how to do read the stored codes.

<SIZE size="117">When you turn the key to either the "on" position or the "accessory" position and absolutely nothing happens. (No noise, clicking, singing, power, no nothing.)</SIZE>

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  • Then the first place you should check is the battery.
    If nothing happens when you turn the key, either the battery is totally dead or the battery connections are bad somewhere between the battery and the rest of the car.
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  • Use a multimeter and check the voltage between the positive battery terminal and a good ground. The voltage should be between12 and 12.8 volts, if the voltage is lower, charge the battery or jumpstart the car.
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  • If the battery voltage is above 12 volts and the car wont start, it's time to check the battery connections.
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  • Remove both the positive and the negative battery cables. Use a wire brush or steel wool to clean both ends of the connectors. Reinstall them and make sure that they are on nice and tight.
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  • If none of the above steps gives you power inside your car, I would have the battery load tested at a local shop or parts store to confirm that the battery is good or bad.
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  • Note: Test your battery. Try charging the battery using jumper cables or battery pack, start the car. Let the car run for about 10 minutes. If the car doesnt die, its time to replace the battery. If the car dies during the 10 minutes your alternator is shot, time for a replacement.
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<SIZE size="117">Your car has power (radio, headlights, light up fuzzy dice, etc....) but the engine will not turn over.</SIZE>

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  • The main thing that will cause this problem is the starter.
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  • Using your trusty multimeter, check for voltage to the starter solenoid. If there is atleast 12 volts to the solenoid, have the starter tested at an auto parts store because the starter solenoid or the starter motor itself may be the problem.
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<LIST>
  • If there is no power to the starter solenoid, the fusible links may be fried. The fusible links act like inline fuses to protect the solenoid and starter motor, if they blow for some reason, the car will not turn over. Check along the battery cables from the battery to the starter, looking for any melted or charred fusible links. Remember that if the fusible likns blew, there is probably something that caused them to go, so make sure to check your wiring and grounds before just replacing the links thinking that will completely solve your problem.
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  • If you hear the starter cranking, but the engine itself will not turn over, remove the starter and see if the starter gear teeth or the flywheel teeth are badly worn. This could be caused by the starter being improperly shimmed.
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<SIZE size="117">You turn the key and the engine cranks, but it still won?t fire up.</SIZE>

** This section is long and quite complicated, so I will try to break it up as best I can.**

<SIZE size="134"></SIZE><LIST>
  • <SIZE size="134">Ignition:</SIZE>
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<LIST>
  • Before continuing on with this section, check to see that all of the spark plug wires are firmly connected to the coils and the spark plugs and that they are on in the correct order (I cant tell you how many times that is the problem!).
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<LIST>
  • First you want to check to see if you are getting any signal to the spark plugs. The best way to do that is to gap one spark plug to unpainted, grounded metal on the car. (engine block, heads) More detailed instructions can be found here.If you have a strong spark, move on to the next section.
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  • If you have no juice going to the spark plugs, remove your coilpack assembly and have it tested at a shop or parts store.
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  • If the coils and ignition control module tests out fine, you should check to see that the ECU is getting a signal from the crankshaft position sensor. To test the CPS sensor, check the resistance, it should be close to 980K ohms, if it is open, then the sensor is bad and it should be replaced.
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  • If, for some reason, you replace the defective coilpack assembly along with the crank position sensorand your car still won?t run, look into replacing the ECU. If you have gotten this far and still need help, post a thread as I will not go into detail about that here.
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<SIZE size="134"></SIZE><LIST>
  • <SIZE size="134">Fuel:</SIZE>
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  • **If you don?t remember the last time your fuel filter was replaced. Do it NOW, it is cheap and a new one will not hurt your car, even if it doesn?t solve the problem.**
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  • If your ignition system is fine and your car wont start, the fuel system needs to be checked.
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<LIST>
  • Check the fuel pump to see if it is working properly. When you turn your car ignition to the "run" position (the one before the momentary start position), you should hear a whining noise coming from the fuel tank. It is better to have one person work the ignition and another person to crawl under the rear of the car and listen in the area of the gas tank for the fuel pump.

    If there is no noise from the pump, depress the schraeder valve on the driver's side of the fuel rail. If gas comes squirting out, your fuel pump is probably not the problem.

    If no gas comes out, check the fuel pump fuse, wiring and the relay. If they are fine, test the pump and replace if necessary.
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<LIST>
  • If the fuel pump is working properly, the last thing to check in the fuel system are the fuel injectors. (assuming there are no huge gas leaks from any of the fuel lines.) To test the injectors the best way is to borrow a set of noid lights from a parts store and hook it up to the injector wiring harness. If the injectors are getting a signal, the lights will flash when the engine is cranked. If the noid lights flash, then you have a injector pulse and something is wrong with the injector itself. Remove the injectors and check them to see if they are plugged up and replace if necessary.
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If your car still wont start, look here for more information on getting your car running again and some of the other mechanical problems that can prevent your car from running well.

That is about all I have for now. If anyone has any corrections or additions that they want to add, pm or E-mail me and I will add the information if necessary. I hope that this little write-up is at all helpful to some of you.

Thanks to Soup and lotsogas for help with this write-up.

Brad
 
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