How many ohms should a fuel pump relay have?
You should read about 70 ohms. If the meter reads zero ohms, the coil is shorted and your relay is bad. If the meter reads infinite ohms, your coil is open and the relay is bad.
What should fuel pressure be when fuel pump relay is activated?
If the fuel pump relay is activating the fuel pump, then it’ll register about 56-62 PSI even if the engine does not start. Any fuel pressure below 50 PSI and the engine will NOT start. If you do see any fuel pressure below 50 PSI, the fuel pump although working, is not creating enough pressure to start the engine and is defective.
How can I tell if my fuel pump relay is defective?
It’ll also show you how to bench test the fuel pump relay in a step-by-step way to find out if it’s defective or not. Contents of this tutorial: Before You Start Your Fuel Pump Relay Diagnostic. TEST 1: Swapping Out The Fuel Pump Relay. TEST 2: Making Sure The Fuel Pump Relay Has Power. TEST 3: Bypassing The Fuel Pump Relay.
How to test a GM 4.3L fuel pump?
More GM 4.3L, 5.0L, and 5.7L Tutorials. It’s very important that you start off your fuel pump relay diagnostic by first testing the fuel pump pressure with a fuel pressure test gauge. If the fuel pump relay IS NOT activating the fuel pump, the fuel pressure test gauge will register 0 PSI when cranking the engine.
What is the PSI of the fuel pump?
If the fuel pump relay IS NOT activating the fuel pump, the fuel pressure test gauge will register 0 PSI when cranking the engine. If the fuel pump relay is activating the fuel pump, then it’ll register about 56-62 PSI even if the engine does not start.
If the fuel pump relay is activating the fuel pump, then it’ll register about 56-62 PSI even if the engine does not start. Any fuel pressure below 50 PSI and the engine will NOT start. If you do see any fuel pressure below 50 PSI, the fuel pump although working, is not creating enough pressure to start the engine and is defective.
Why is my fuel pump relay not working?
I have replaced the fuel pump relay oil pressure switch and computer. If you’re not getting a signal for fuel, then you either have a faulty crank sensor, or bad ignition module. But the truck runs great until you cut it off. If you poor a little gas in the intake to get it started would that only effect the starting ? Ok.
Why does my 1994 Chevy S-10 not start?
1994 Chevrolet S-10 4.3 tbi. I never get the signal to turn on the fuel pump or fire the injectors but if i poor gas in the intake once the truck starts it runs fine. Any ideas ? I have replaced the fuel pump relay oil pressure switch and computer.
More GM 4.3L, 5.0L, and 5.7L Tutorials. It’s very important that you start off your fuel pump relay diagnostic by first testing the fuel pump pressure with a fuel pressure test gauge. If the fuel pump relay IS NOT activating the fuel pump, the fuel pressure test gauge will register 0 PSI when cranking the engine.