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There isn't one.
What testing have you done?
Make sure battery has a full charge. If it cranks good but won't start, have a helper crank it while you visually check for spark at the plugs. If spark everywhere, use a gage and check proper fuel pressure and fuel injector pulse. If your missing everything check for rpm signal. Any applicable trouble codes?
When you first turn on the key, no crank, can you hear the fuel pump run for a couple seconds? There is a fuel pump fuse in underhood fuse box.
Not sure what the spec should exactly be. But If you hook up a pressure gage to the fuel rail and turn the key to the on position it should build pressure to around 9bar or 130psi and hold it. If it looses pressure then you have 1 of a few possible problems.
-leak in the fuel line.
-bad check valve in fuel pump
If nothing happens you have a bad fuel pump. But if it does hold pressure then your engine is getting fuel. Now turn the engine over and the gage should read in the range of 18-25bar or 260-360psi. If everything checks out fuel is most likely not the reason for your problem.
If you have no fuel pressure at the engine when key is on, the pump is not coming on. Check fuel pump fuse, check fuel pump relay (relay should click when key turned to on-put finger lightly on it and feel for click when someone turns key to on). If no click, signal from computer may be lost, ground for relay may be lost, or relay may be bad. If it clicks, wiring from relay to pump may have failed, or the relay's main power source may not be there at relay-find the fuse link or maxi-fuse that powers that relay. One terminal at relay should be hot at all times-can check for that with a test light. If pump is working and you do have fuel pressure, you will need to check injector circuit. Post back if questions, or need further help.
The fuel pump relay is controlled by the PCM which uses the gray and black wires all the way back through the chaissis to the fuel pump. With the key on and no pressure at the rail the pump should be running. If there is no power out of the PCM (Power Train Control Module) to the fuel pump relay the fuel pump will not work
Hello: 1st, pumping the accelerator on a fuel injected GM car does NOT do any good. In fact if you put the accelerator to the floor you put the system in the lean mode ie, reduce fuel. You will need a fuel pressure gage and there should be a schrader valve on the fuel lines/fuel rail where you can connect the fuel pressure gage. The fuel pressure should be about 10 psi if you have throttle body injection. Is your car a 4 cylinder? If its a 4 cylinder you may not have a schrader valve to connect the pressure gage. You will need a high dollar kit to tap into the fuel line. Have someone attempt to start the car and you remove the air cleaner an see if the injector is spraying fuel.
There is a relay in the engine compartment And there also should be a fuse in the relay box for the pump it will be marked on the lid when you remove it. There is another fuse in the inside of the suburban for the computer and for gages make sure they are OK, pull the fuse out and when looking at the fuse make sure it is connected the s should touch each spade terminal. if all the fuses are good then turn the key to the run position and listen for the fuel pump in the tank it should run for two seconds, if you don't hear the fuel pump run and the fuses are OK then your oil pressure switch is defective and depending on which engine you have will determine where the location will be for the oil pressure switch. The oil pressure switch will shut off the power to the fuel pump if it does not show oil pressure and depending if you have a oil gage or not you will not know for sure. you will not have power to the relay unless the vehicle is cranking over. also I can't remember if it has a roll over switch on that model, check the glove box or on the side where you fill up the fuel tank your it should be on that side I hope this helps And thanks for using fix-ya.
Spark......EQUIPMENT NEEDED: 1) fuel pressure Gage....Advanced Auto = $45..... 2) needle nose pliers ( fuse pull ).. There is a fuel pressure access valve located on the fuel injector rail. The access port or "shraider" valve has a black or gray screw on cap. Remove the cap and you will see the valve. CAUTION: The fuel rail is under pressure....before installing the pressure gauge, relieve pressure by starting the engine and removing the fuel pump fuse from the under hood fuse box...... Once the engine quits, turn the key to the off position and safely install the pressure gauge. Put a rag around or under the access valve to catch any drizzling fuel. I always prefer to do this when the engine is cool. Install the pressure gauge, start the engine, check for leaks and read pressure output at idle, record pressure reading. Also, it should be checked under load but you will need another person to help.
Once you have shut the vehicle off watch the pressure gauge, it should remain steady and not leak down.
Let me know what the readings are.