On any car with electric fuel pump.If you put an amps draw meter on the fuel pump wiring and the fuel pump draws more than 3 amps the fuel pump is bad.
Test the electrical circuit for the fuel pump , lab scope an amp test meter ! Find the fuel pump relay ,pull it out ! Look on bottom of the relay . Should see four sets of numbers , 30,87 an 85,86 . take a DVOM - set on DC amp's . put one lead at 30 an other 87 . This is power to fuel pump . Should see 4 - 6 amps current draw ! Videos on youtube showing this !
Never tried it, but it should work because it\'s a pain to drop the tank and eyeball it. Electric fuel pump in the tank... ok. It\'s a motor and motors draw current right? One could -possibly- yank the fuse and replace it with a ammeter (DVM on Amps). If the circuit is complete, it should pull 3-4 amps minimum when the pump is running I\'d think. If the circuit is open, it won\'t draw anything, zero or close to it. There may be a small draw from other stuff that\'s on the fused power but the difference should be obvious. Better yet, drop the meter into the relay contact circuit. The only thing that should be on that one is the fuel pump itself. Put one lead on the +12 battery and the other lead into the contact block that goes to the pump. It should turn on. If you\'re squirmish use a pigtail fuse at about 4 amps. The coil and contact arrangement is usually printed on the side of the relay. If not, the contacts are usually on beefier terminals than the coil. If all else fails, get the chassis service manual and look up the color codes.
If you don't have any idea what to check next, maybe now is the time to take the vehicle to an auto electric repair shop that specializes in tracing wires. You may have a short to ground somewhere, or an accessory, that is drawing current when the vehicle is off, to the point of making the battery go dead if sitting more than 15 hours.
One check that you could do yourself, with the proper tool, is to check the amps being drawn when the car is off. If the amps drawn is above .2 Amps, then it's too high of a draw. The symptoms you describe sound like it is more like 2 or 3 (or more) Amps being drawn on the battery.
Try to remove fuses to various accessories to see if that reduces the amp draw on the amp meter.
I would use an Amp meter that is inductive and has a claw that opens and surrounds the positive or negative battery cable and measures current without having to actually remove any cables from the battery, and connect in between the battery terminal and the battery cable.
Let's say, for instance, that it was an accessory like a radio that was drawing an inordinant amount of electrical current. Then, if you removed the radio fuse, the draw should go from 2 or 3 amps down to below 0.2 amps. So, that's what I would do to try to narrow down the possibilities.
×