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1993 GMC Vandura 2500 Question: starting problem

 

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stras, 5.7L V8, Washington, DC, May 19, 2009, 17:42
 Rookie

Van stopped running suddenly. can not start it. Previously two weeks before i also had a starting problem but discovered the distributor cap and rotor were very bad. Replaced them and it started up first time. However i may have crossed a couple of plug wires as it was running bad i.e.missing for a couple of weeks until it stopped running again. Now i replaced all the plug wires and am not sure if the wires are in the right order. My Chilton book is not explicit in where to start the firing order on the top of the distributor cap so now i am all messed up and uncertain where to start. The second part of this problem may or may not be associated with the correct placement of the wires as when i turn the ignition on it turns over, does not fire though gas is flowing and when i turn the key in the ignition off the engine keeps on turning over until i disconnect the battery. When it stopped running i checked the spark on one of the plugs and there was no spark. I have had the alternator checked ,it is OK. I replaced the ignition switch and had the distributor module checked and that is OK. Can not see a crossed wire any where and still have to check the starter solenoid. Any advice or recomendations would be appreciated.

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  • Answer #1

    May 22, 2009, 10:16
     Master

    There is some free service information available from AutoZone - www.autozone.com. They may be able to help with the location of #1 cylinder on the distributor cap. If they are of no help you can try the following: With the #1 cylinder on top dead center on the compression stroke the distributor rotor should be pointing to #1 cylinder. Remove the distributor cap and see which tower the rotor is pointing to and that should be #1. You can then set your wires from there.
    For the engine to continue to turn over after you release the ignition switch something must be continuing to power the starter. In order to check the circuit you will need to disconnect the smaller purple wire from the starter. With the purple wire disconnected, you should have power on that wire only with the ignition in the "crank" position. If you have power at any other time you will need to check the rest of the circuit to find out why. If the tests on the purple wire are OK then the fault may be with the starter.

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    stras, May 27, 2009, 15:12
     Rookie

    I received your answer to my questions and you were correct that the solenoid on the starter motor was bad. I replaced the starter motor and coil and now it turns over fine. I have yet to test the computer and the unit that the high tension lead wire is connected to that gives power to the distributor. I was told to check it with an ohhmeter and that there is a certain range it should be in. I do not know what range it should be but have a friend who can help me test it as i do not know how to do it. Any tips are welcome. The computer, the ecm seems to have a black wire at the back of it that is not connected to any thing. I am not sure what it is for. The wiring to the computer has been messed around with by previous owner and there are wires disconnected. Also there is a second black box that i am not sure of its function. It may also be part of the computer system. I am trying to rectify the wiring problems and get this van sorted out. My friend knows where there is another van similar to mine for sale for $2500 which would be a lot better than mine so i could use this as spares but for now i need to get it running. Thank you Trevor.

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