1989 S-10 fuel system

I have an 89 S-10 that won't run. If you prime the "carburator" it will start, but not run. It gets fuel to the injector, but not out. I have changed the injector, no help. I just changed the control box - still no fuel. Can anyone help?

Stu

Look on passenger side under the hood just above the heater unit. See a grey wire with a connector not hooked to anything. This is the factory prime wire direct to fuel pump. Run a jumper wire from battery to this wire and see if engine will run. If so you have a bad relay or something, if not you have a bad fuel pump or clogged filter. I'd suspect your fuel pump is too weak to push fuel through the injector, needs about 9 psi to run.

Look on passenger side under the hood just above the heater unit. See a grey wire with a connector not hooked to anything. This is the factory prime wire direct to fuel pump. Run a jumper wire from battery to this wire and see if engine will run. If so you have a bad relay or something, if not you have a bad fuel pump or clogged filter. I'd suspect your fuel pump is too weak to push fuel through the injector, needs about 9 psi to run.

I ran a jumper from 12 v to grey wire and the engine will still not start.
During the process I think I may have blown the fuse to the fuel pump. I disconnected the fuel line and nothing comes out unless I connect 12v to the grey wire. Can anyone tell me where in the engine compartment the fuse is located?

Stu

You might have a relay box under the hood. First place to look is in the cab fuse panel. Pretty sure that's where mine is. The relay box under the hood would most likely be black and tucked in one of the corners. Should be easily accessible.

The relay block your looking for is on the firewall either driver or pass. side. One thing you should check is if your getting power to the injecter, use a "Noid" light tester on it, an injectoer is just a solinoid valve which requires power to open, no matter how much fuel pressure you have if it doesn't open, you won't run. My other question is does your fuel pump actually turn on? when you turn the key to the "on" postion you should hear it hum...if not then i would be looking at the relay or fuse....i think the fuse is in the main panel but not sure. Hope that helped