Fuel pump won't work
 

Hello, I'm from France, I have a blazer s10 from 2000, I bought it 5 months ago, at the beginning it was just running on 5 cylinders, so I changed the spark plugs, spark plug wires and the distributor, and today it's impossible to start it, the fuel pump doesn't want to turn on. The engine runs perfectly on 6 cylinders with start-pilot. I put a new relay, I jumped the relay, nothing works, while before it worked very well.

1. Have you confirmed no fuel pressure with a fuel pressure gauge?
2. Do you mean that it starts with starter fluid sprayed into the throttle body?
3. Do you have and know how to use a digital multimeter?
4. If so start by confirming 12v at the fuel pump priming connector for a few seconds at key on.

George

1: There is 0 psi at the valve just before the injectors, the tank is more than half full, and there is no fuel in the fuel filter.
2: Yes, the engine starts perfectly well with starter fluid into the throttle body.
3: I have and can use a multimeter.
4: Where is the fuel pump priming connector located, any datasheet to help me ?

Here you go. The priming tab is in the UHFB in the engine compartment.


George

Thank you very much for helping me !
So I checked if there was power at the fuel pump priming connector and there is 11V after I turned on the ignition. The battery must be low because I have my dome lights that consume power when I reconnect my battery. Is it a problem for the pump to have 11V or is it necessary to supply it with 12V?

I do not know what the dropout voltage is for your fuel pump. I would charge the battery, knock off the surface charge with the headlights for 20 seconds and then make sure that the resting voltage is 12.6v at the battery then remeasure. If you are good at the priming tab then you will need to get under the truck and measure voltage and ground at the pump connector. Its hard because everything is above the fuel tank but the best measurement is always to leave everything connected and back probe the power and ground so you see the voltage under the pump load.


George

Thank you very much, I will tell you tomorrow after charging the battery and check if the voltage is good.

I have heard that sometimes a banging on the gas tank can motivate a cantankerous fuel pump. No guarantees, just a maybe.

Sometimes that will get you home but then you have a date with a set of jack stands as soon as you get there.


George

I have some news about my Blazer, it's the ground strap that connects the fuel pump to the frame that broke with corrosion, and I can't figure out how it was connected before it broke.