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fuel pump testing?

Featured Replies

hi i believe either my fuel pump is no logner working or not getting enough voltage to run it. yesterday i pulled the whole pump assembly out and i was wondering how i could test the pump by putting 12v directly to it and see if it spins? thank you

if you have it out just change it they are very intermitant so may work on bench then leave you stranded its a good idea to just put in new one to rule out any problems it may have.

  • Author

but i dont have alot of money at the moment and wanted to test it because im only getting 10 volts to it so it may be a wiring problem and not the pump.

 

*EDIT*

okay i unplugged the red and black electrical connector that goes directly to the fuel pump and the other 6pin connector the red connector is black and burnt and the plastic connector is melted a little on the red side. the black connector is silver and not burned and intact.

Edited by Scotty1419

The fact that the connector was melted means there was a bad connection at that point and that is why the supply voltage to the pump was low. Bad connections cause a voltage drop to occur when current flows through the added resistance. Repairing or replacing the bad connection should allow full voltage to get to the pump motor.

  • Author
The fact that the connector was melted means there was a bad connection at that point and that is why the supply voltage to the pump was low. Bad connections cause a voltage drop to occur when current flows through the added resistance. Repairing or replacing the bad connection should allow full voltage to get to the pump motor.

 

i see what your saying but the voltage drop was before the bad connection i read it on the 6pin connector that plugs into the fuel pump assembly connector that sits ontop the lid

If you still want to test the pump you can apply 12 volts to the motor leads and see what happens. Make sure to try and get the polarity correct.

 

You stated earlier the voltage drop was happening more upsteam in the wiring so then you will need to find out where that is happening. It may be at the pump relay.

  • Author

i bench tested the pump with a 12v battery and it ran fine.. i checked the relay and fuse both were good

Hopefully you checked the relay while it had a load on the contacts otherwise if there was voltage drop problem with it the drop wouldn't take place and it would appear to be ok voltage wise. Now if you measured the resistance between the contacts while they were closed and no resistance was read then it should be ok.

  • Author

okay well i cleaned up the burnt conector and made it so it made a connection again and put the pump back in the car. the pump works now and the car starts but its ticking really bad.. i think what could be due to alot of atf from the leaky power steering pump getting down in the oil through the spark plug hole that i had the spark plug out of when i was towing the car.. (stupid me) and also all the plugs are really black so im gonna replace them and change the oil and hopefully that will stop the ticking.. the idle rpms are also at like 1.5k when i start the car up.. also there is this buzzing noise which sounds like its coming from the Coolant temp sensor that runs for a couple minutes after i shut the car off..

To see if there is a backfeed problem coming from the alternator disconnect the small connector on the back side of the alternator while the engine is off and the device is making the noise. If it goes away when you remove the connector then there is a problem.

  • Author
To see if there is a backfeed problem coming from the alternator disconnect the small connector on the back side of the alternator while the engine is off and the device is making the noise. If it goes away when you remove the connector then there is a problem.

 

thank you for that helpful piece of info. i will try this tommorow after i change the oil and put plugs in

the idle moter times out should buzz for about 30 seconds after car is shut off normal operation

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