Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Cars & Trucks (https://www.askmehelpdesk.com/forumdisplay.php?f=41)
-   -   89 honda civic intermintent fuel pump power (https://www.askmehelpdesk.com/showthread.php?t=508752)

  • Sep 18, 2010, 05:28 PM
    civic8998
    89 honda civic intermintent fuel pump power
    My fuel pump gets power intermintely. Relay checks out fine.has spark.CEL and all other Dumbie lights go off normally after two seconds. Fuel pump is only a year old. I get 12.62 at the connector then drops to 10.35 a second later even when the fuel pump turns on it still does that. I've replaced my MAP sensor and igntion switch hasn't fixed the problem. I don't have a clue what the problem is any help would be greatly appreciated! Thank You!

    PS when I have more time I will get more information
  • Sep 18, 2010, 05:33 PM
    TxGreaseMonkey

    This link may help:

    https://www.askmehelpdesk.com/cars-t...ml#post1245523

    Be sure to clean the main ECM ground, located on the thermostat housing.
  • Sep 18, 2010, 05:47 PM
    civic8998
    Hi TxGreaseMonkey I hope you would answer this I've been threw pretty much all your posts

    What topic should I choose in that link that you think would help me out the most? There are quite a few
  • Sep 19, 2010, 05:23 AM
    TxGreaseMonkey

    In the link I gave you above, I would perform all of the tests listed--it shouldn't take too long.

    The contacts in the relay may be pitted. As the cross-sectional area erodes through pitting, the resistance goes up by a square factor. Based on the formula Area of a Circle = Pi x R-squared, as the effective cross-sectional area of a points gets cut in half, the resistance goes up four fold. This means that the amperage available to the fuel pump would be 1/4 of what it would be otherwise, when you plug these values into Ohm's Law. Ohm's Law states Amperage = Volts/Resistance. As resistance (Ω) doubles, amperage is cut in half.

  • All times are GMT -7. The time now is 07:08 PM.