Quote:
Originally Posted by kapkanimd
Can you clarify what you are saying here? What is it you are testing with the pump jumper?
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To test the current draw of the fuel pumps, the quick check to see if the current draw is normal is to set your VOM (volt-ohm-meter) to read AMPERES:
1st!: Before making any connections to anything, switch the (usually RED lead) to the "A" (Amps) port of the meter. (
AND! Remember to disconnect the leads from the meter BEFORE you return it to read voltage or ohms.
Otherwise you will likely blow the meter's internal fuse if later you accidentally attempt to read voltage while plugged into the amperes port!)
2nd: WITH THE
IGNITION SWITCH IN THE OFF POSITION, jumper the (black) lead of the meter to the the fuel pump diagnostic connector - the black (or sometimes white) connector attached to the short read wire (jutting out of the wire loom between the windshield wiper and the brake booster. (Use an alligator jumper to make this easier -- see photo))
3rd: Touch the other meter lead (red) to the POSITIVE battery terminal and read the current on the meter. Barring a bad fuel pump(s) or blown fuses, each pump should draw 4-5 amperes for a combined total of 8-10 amps. If one of the fuel pumps is inoperative, a reading of 4-5 amps indicates one pump is not operating. Check the fuses before assuming fuel pump(s).
WHEN FINISHED, DISCONNECT THE LEADS FROM THE CAR AND REMOVE THE RED JUMPER FROM THE METER'S AMPERES PORT AND PLACE IT ON THE OHMS/VOLTAGE PORT ON THE METER BEFORE READING VOLTAGE.
Note: If the pumps are drawing the typical amount of current (4-5 for each), chances are the pumps are operating OK. Otherwise, each pump has a fuse to consider. And, if fuel pressure (which I suggest you also monitor while conducting this test) is not in the 43-45 ish PSI (ore better) range, there may be a delivery issue (e.g., bad check valve or kink in the line, etc., etc.)