Question about 1999 Chevrolet Silverado 1500

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1995 silverrado fuel pump relay

My fuel pump relay will not click , the wire from the relay to the pcm , when you first turn key on the voltage will be b+ then it will drop off to 4.5 volts , is that norm , i have pulled the pcm and tested the wires and checked the wire to all other pins , all clean so the wire it good , does any one know if that is normal?, that truck has a bad hesitation ,but if you let up the tps just a little it is a lot better , at low speeds , on the freeway it does not hesitate, so at high rpms it's ok , any idea's ,thanks

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  • Mark Harrison
    Mark Harrison Jan 24, 2009

    the relay was bad but the hesitation is still there ,i was checking the timing and i noticed that if you raise engine speed and watch the timing it will jump a little them jump to the max and as the rpm's come down it will back and forth , so does the ign module in the distributor control the timing or the pcm? no codes

  • Mark Harrison
    Mark Harrison Jan 24, 2009

    the relay was bad but the hesitation is still there ,i was checking the timing and i noticed that if you raise engine speed and watch the timing it will jump a little them jump to the max and as the rpm's come down it will back and forth , so does the ign module in the distributor control the timing or the pcm? no codes

  • Mark Harrison
    Mark Harrison Jan 24, 2009

    i did test the tps and it checks out ok

  • Mark Harrison
    Mark Harrison Jan 24, 2009

    i replaced the relay , still have problem,thanks

  • Mark Harrison
    Mark Harrison Jan 24, 2009

    thanks

  • panchyson Jan 30, 2009

    I can start the truck just fine, it will run for a few seconds and then the engine dies. It seems like the fuel pump but I haven't checked it yet. Does anyone know what the problem might be?



    Thanks much!



    KP

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  • Master
  • 1,990 Answers

The Power Numbers are Correct. Just replace the Relay and you should be just Fine.

Posted on Jan 24, 2009

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