Fuel pump fuse keeps blowing. replaced fuel pump , still blows,disconected air bypass valve, still blows, doesn't blow if i disconect the fuel tank wiring plug. how can i test the sending unit wir

disconect wiper motor and ck again if dont blow the fuse you need a new motor if blow the fuse you have a short to grown

e fuel pump motor may have failed, causing a short and blowing the fuse. Try unplugging the fuel pump connector at the pump, then turn key on with a new fuse in place. If the fuse blows again, it could be a short in the pump's wiring. If the fuse doesn't blow, it is likely a bad pump.

Sounds like there's either a short on the fan motor or on the wiring. Try and disconect the fan and see if the fuse blows then when you switch it on (of course being disconnected it wont spin). If it blows again it could be 'wire chafing' See... http://www.croberts.com/chaf.htm

If it doesnt blow then it probobly is the fan motor itself shorting out.

Just be aware just moving the wiring might move the shorting wire away from it's short as it were and the problem may seem miracilsly fixed but that maybe temporary untill the bare wire touches something again.

SAFETY NOTE
USING THE FUSE OF THE CORRECT RATING SEEMS SILLY TO SOME PEOPLE... BUT IT IS THE WEAK POINT THAT MELTS *BEFORE* FIRE STARTS.

REST ASSURED THE FUSE IS DOING IT'S JOB HERE, DON'T BYPASS IT!

might be the pump its self goosed if its grounding inside the pump it will pop fuses dont disconect ecu though even touching them can knack them the static from your hands can wipe the programing where rubber gloves if you need to handle them hope this helps ivan

The fuel injection fuse should also power the injectors. If the fuse is blowing, I would think one of the injectors has shorted to ground.
Have you checked them ?

Follow the wires up from the fuel pump to the front of the car. You most likely have a wire that rubbed though its coating somewhere and is causing it to ground out on the frame and blow the fuse.

it sounds like an injector problem get a code reading on it to find out which cylinder and the replace that injector.

Check the fuse to the fuel pump.
The issue is repeated blowing of the fuel pump fuse. This occurs randomly and without warning, normally when medium to high throttle is applied. Generally the RPM's will fluctuate briefly before the fuse blows, which cuts off ALL power to the vehicle.
Especially dangerous on a highway! The first mechanic found a TSB related to the fuel pump resistor, and its default location in the wheel well can cause premature corrosion. Replaced it and relocated as per the TSB.
You can bypass the resistor, it's simple and free. You bend pin 85 on the fuel pump relay #15, in your engine bay fuse and relay box. Good luck and keep me posted, at worst ti's going to be a bad fuel pump and your going to have to drop the gas tank to replace the fuel pump. When you bend the #85 pin from the relay, will set the fuel pump on high mode bypassing the resistor.

Low fluid or bad therostat if it does it when engine is warmed up.Heater control valve replaced or mixing valve? If so you have a vacuum hose disconected

relays get hot and thats normal but the fuse burning might be caused by a defective 02 sensor or oxigen sensor disconect sensors and see if keeps blowing the fuse
other cause of burning fuse might be injectors but if you had a mufler or exaust repair latetly most likelly 02 sensor is shorting