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1995 Chevrolet Impala SS Question: 1995 impala has sitting a while and won't start

 

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thomas g, Nashville, TN, July 05, 2010, 07:34
 Rookie

replaced battery, fuel pump {was told this was why it was parked} also replaced pump wires and inspected pass through wiring harness. pump runs when key is on but car will not fire

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    patrick mannion from Greg Solow's Engine Room, July 05, 2010, 08:03
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     Master

    An engine needs three basic things to start, mechanical integrity (the engine's components must be in synchronization with each other and the engine must be able to develop compression), the engine must get fuel injected into the cylinders (fuel must be injected into the engine ( there is a computer that takes inputs from many sensors on the engine, interprets these signals and decides when and how much fuel to inject into each cylinder) finally the engine needs spark to ignite the fuel injected into the engine, (the spark is also controlled by the vehicle's computer deciding when the spark arrive at the spark plug). If the components in the engine are not in synchronization due to a broken or "slipped" timing belt or chain the engine will not develop adequate compression to start and run properly. If any engine sensor has failed (crank angle sensor, camshaft position sensor, intake manifold pressure senor/air flow meter, coolant temperature sensor) any of these will cause the engine to fail to start by causing a loss of spark or fuel delivery. All these components need electricity to function, a failed fuse, relay, open or shorted electrical circuit could cause the computer, fuel pump or ignition system not to function. Unfortunately there are too many things that could cause your engine not to start to be able to pin point anything to specifically look for. Check for fuel delivery at the fuel rail in the engine compartment, check that the fuses and fuseable links are OK and check for ignition spark.

    Next I would get a friend to crank over the engine, listen to the injectors to hear if they are triggereing. Use a screw driver with the handle end to your ear and the metal tip resting on the injector, on cranking you should hear a rapid tick tick tick of the injector opening and closing. Look t the dash does the Check Engine/Service Engine soon light come on if not your computer is not working correctly or not getting power.
    Do you have good repair information?
    There is a company that independent auto repair shops "buy" their information from that offer a very reasonable service to do it yourselvers. You can get a one week subrcription or year subscription very cheap. The information is year make and model specific repair procedures, service bulletins, component locations, wiring diagrams ect.... great quality information same as the professionals have ,much better than generic workshop manuals from parts stores, much cheaper than the factory manual try http://bit.ly/mitchell_repair_manuals_online
    and get an online repair manual subscription.

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    thomas g, July 05, 2010, 08:11
     Rookie

    fuses were all good, will check or replace fp relay. fuel line comes to the rail from the back passenger side( i think )should i take it loose and turn key to start to verify that fuel is reaching. we have some spark because it would fire very short but not run. if i have fuel at the rail what would be next?

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