QuestionQUESTION: drove home normal. then car would not start, and could not hear fuel pump run when key turned on. replaced relay, no joy. do you think its the pump? is it in the gas tank? can i do it myself at home? i read the fuel filter my clog and cause this. 5.7L gas 4WD 1/2 ton 1500
ANSWER: First, you want to make sure that it is the fuel pump. The fuel system can hold pressure for a good while, so you wouldn't necessarily hear it run. Just to make sure, look on the fuel rails, one or the other, that feed the fuel to the injectors. You'll see a fitting that looks like a tire valve stem. Take the cap off (if someone hasn't already) and have someone crank the engine while you hold down the pintle in the middle of the valve (just as if you were letting air out of a tire). If the pump is working, fuel will squirt out under pretty good pressure. If it doesn't, then the fuel pump is probably bad since you already replaced the relay (with a brand-new one, right?). Also, there is a fuse, so check that, too. To replace the pump, the fuel tank has to come out of the truck, the pump is inside of it. It is much easier to do this in a truck than in a car. Try to siphon as much of the fuel as you can out of the tank, to make it lighter, undo the straps and drop it down. Before you take the pump and float assembly out of the tank, get a couple of jumper wires and see if you can get the pump to run by hitting it with 12v while it's still in the tank. If the pump runs, then there is a problem with the wiring. Oh, and yes, you should replace the fuel filter as well, which is simple to do and cheap. Do the jumper test with the old filter off (before you put on the new filter) so you can verify whether or not fuel is being pumped. And for God's sake, don't smoke or allow any flame or spark near the truck while you are doing this!
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QUESTION: Thank you. Yes, the relay was new. I admit I cannot find the fuse...I looked under the hood where the relay was; and to the left of the driver dash area where the other fuses are, to no luck. Can you give me more info on the location? thank you.
Answer The fuse should be in the fuse box inside the cab. It may not be labeled "fuel pump," though. Get out the owner's manual and look at the fuse diagram, which tells you which fuse does what. That should steer you straight. But, believe me, there IS a fuse.
