20 amp fuel pump fuse blows. car wont start. 40 amp fuse restores power. what is causing 20 fuse to blow. use to blow.

CK WIRING HARNESS FOR SHOT TO GROUND

Unplug the connector at the fuel pump. Install a new fuel pump fuse. Try to start the car. Does the fuse blow? If not that the problem is probably a bad fuel pump. If the fuse does blow with the pump disconnected than you need to look for a short in the power supply to the fuel pump.

A fuse will blow for 2 reasons . 1) If the device has a Short in the circuit that runs through this fuse. 2) If the device draws more amperage from the power source through the fuse than the fuse will handle. ex. if a fuel pump or starter has a 20 amp fuse and the starter/fuel pump is going bad and draws 30 amps it will blow the fuse. A fuel pump on a 1996 vehicle is located in the fuel tank and is kept cool by the surrounding gas and the gas that flows through it. Overheating a fuel pump is virtually impossible. That being said there is a High probability that replacing the fuel pump and relay will fix this problem. It is quite common for this to occur in the GM vehicle of 1996. When the pump starts to fail, it draws an excessive amount of amperage and would blow the fuse. Hope you find this information useful.

A fuse will blow for 2 reasons . 1) If the device has a Short in the circuit that runs through this fuse. 2) If the device draws more amperage from the power source through the fuse than the fuse will handle. ex. if a fuel pump or starter has a 20 amp fuse and the starter/fuel pump is going bad and draws 30 amps it will blow the fuse. A fuel pump on a 1996 vehicle is located in the fuel tank and is kept cool by the surrounding gas and the gas that flows through it. Overheating a fuel pump is virtually impossible. That being said there is a High probability that replacing the fuel pump and relay will fix this problem. It is quite common for this to occur in the GM vehicle of 1996. When the pump starts to fail, it draws an excessive amount of amperage and would blow the fuse. Hope you find this information useful.

A fuse will blow for 2 reasons . 1) If the device has a Short in the circuit that runs through this fuse. 2) If the device draws more amperage from the power source through the fuse than the fuse will handle. ex. if a fuel pump or starter has a 20 amp fuse and the starter/fuel pump is going bad and draws 30 amps it will blow the fuse. A fuel pump on a 1996 vehicle is located in the fuel tank and is kept cool by the surrounding gas and the gas that flows through it. Overheating a fuel pump is virtually impossible. That being said there is a High probability that replacing the fuel pump and relay will fix this problem. It is quite common for this to occur in the GM vehicle of 1996. When the pump starts to fail, it draws an excessive amount of amperage and would blow the fuse. Hope you find this information useful.

A fuse will blow for 2 reasons . 1) If the device has a Short in the circuit that runs through this fuse. 2) If the device draws more amperage from the power source through the fuse than the fuse will handle. ex. if a fuel pump or starter has a 20 amp fuse and the starter/fuel pump is going bad and draws 30 amps it will blow the fuse. A fuel pump on a 1996 vehicle is located in the fuel tank and is kept cool by the surrounding gas and the gas that flows through it. Overheating a fuel pump is virtually impossible. That being said there is a High probability that replacing the fuel pump and relay will fix this problem. It is quite common for this to occur in the GM vehicle of 1996. When the pump starts to fail, it draws an excessive amount of amperage and would blow the fuse. Hope you find this information useful.

the problem could be the fuel pump fuses only blow when they are overloaded ie. if you have a 15 amp fuse & the fuel pump or whatever is drawing 20 amps the fuse will blow,if you are using the right amp fuse the fuel pump is drawing too much power & may be faulty or there is a problem with the wiring, a loose connection or the like.....hope this helps....cheers

When this happens the fuel pump most of the time has a short in it.

bad ground to fuse box

use a circuit breaker or paper clip with pliers so you do not burn yourself use paper clip as fuse unplug engine controll sensors 1 at a time and check if problem is gone after each one is unplugged an engine controll sensor is most likely shorting out if you have a map sensor try that first then move on to other components tps,fuel pump ect. till you find wich is fauly causeing short this should help you just be carefull with paperclip am saying to do this instead of blowing expensive fuses