i just picked up an 87 v 30 with a 454 tbi i was going down the freeway and it just died so i got out and lifted the hood took the air filter cover off had my friend turn it over and no fuel at all. it has duel tanks so i tried switching tanks and they wouldnt switch so im wondering if its a fuse that shuts the whole fuel system down or if i only have 1 fuel pump but i thought with duel tanks there would be a pump in each tank i dont know much about the tbi first truck with it thanks for any help
CK5
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no fuel
- Thread starter j250trxr
- Start date
Do you hear the fuel pump whine when the key is turned to "run"?
That doesn't guarantee that you've got fuel pressure to the injectors, but it's more likely.
That doesn't guarantee that you've got fuel pressure to the injectors, but it's more likely.
You'll have to figure out how the switch is tied into the fuel pumps.
Do a search on forcing the electric fuel pumps to run, there's a test for that. I don't think it's your relay, the truck would still start once fuel pressure comes up after a few seconds of cranking.
Got a "noid" light? Check that the injectors are pulsing when the engine is cranking. If they aren't, then it's not a fuel issue.
Also check for spark!
Do a search on forcing the electric fuel pumps to run, there's a test for that. I don't think it's your relay, the truck would still start once fuel pressure comes up after a few seconds of cranking.
Got a "noid" light? Check that the injectors are pulsing when the engine is cranking. If they aren't, then it's not a fuel issue.
Also check for spark!
well i checked the fuel tank switch and that is good, i then checked the wireing with the ignition on and i am getting no power to the switch at all whitch i belive then sends power to the fuel pumps, i hooked up a battery to the wires to the fuel tank switch valve and i then got power to them so i think it might be the fuel pump relay,because the fuse is not blown and i have power to the fuse so it is between the fuse and the fuel tank switch that i am loosing power,has to be the fuel pump relay.thanks for the help dyeager.if you think of anything else just yell
sandawgk5
3/4 ton status
I had this problem on my 87 K5 with tbi 350 and it was the ignition module inside the distributor that had failed. If that goes out the ECM will not let the injectors fire so it looks like a no fuel problem. Use a noid to check and see if the injectors are being told to open. Also do you have spark? That is another sign that the ignition module has gone bad. There seems to be no rhyme or reason or indication when it is going to fail it just goes. Just my experience hope it helps.
Ira
Ira
the ignition module is some thing i will have to check i put a jacobs prostreet ignition on it so i no longer use the stock stuff or so i thought,i put the jacobs on when the pickup coil went out i have been driving it with the jacobs for a while whitch i thought replaced all of that stuff
sandawgk5
3/4 ton status
did the jacobs replace the distributor? If it did I do not know what the jacobs unit replaced the ignition module with. If it did not replace the distributor it is the black module inside the factory distributor that has the 2 weather pac connectors on it.
no it did not replace the distributer but all of the wires are now unhooked that went to the cap and rotor, and i belive all the jacobs really uses are the cap and rotor to distribute the spark the jacobs creates because the jacobs does all of the throttle advance,retard and all that stuff i guess.but the problem i am running into is that there is no current to the fuel tank switch or the fuel pumps.i am not sure if anyone knows but does the fuel tank switch that switches the tanks also carry the electricity that powers the fuel pumps?
sandawgk5
3/4 ton status
Oh I learned something today but sorry cant help with the tank switch power. Did you test the fuel pump relay? Having dual tanks I am not sure what is different if anything.
Ira
Ira
Like I said, the oil pressure switch SHOULD provide voltage to the pumps regardless if the relay is bad...that's solely why the oil pressure switch exists.
Need to check spark and injector pulse, because even if the fuel system is totally dead for whatever reason, you will still have spark and injector pulse. If you don't have one or both of those, you'll just waste time trying to diagnose a fuel problem.
Need to check spark and injector pulse, because even if the fuel system is totally dead for whatever reason, you will still have spark and injector pulse. If you don't have one or both of those, you'll just waste time trying to diagnose a fuel problem.
