[HELP!] I think my fuel system is messing up.

[Viper81]

ok, so yesterday i get ready for work and go to start my truck and it starts right up like every other time then about 3-4 seconds later it just dies... it would not start again. it was turning over but it was like it wasn't getting any fuel.

So i turned off the radio and all the warning chimes and listened for the fuel pump and i didn't hear it buzz like normal when you turn the key to on. (qouted around $500 to fix that!!!! :fire: )

I made it to work then got home and started back on troubleshooting it. checked all the fuses and stuff. Noticed that the fuel pump went through a relay, so i switched it out with a different one (the horn, who needs a horn when i cant go anywhere to use it) and it started on the second try.

But now it's really rough idle and a faint ticking sound after i let off the gas.

My theory: The fuel filter is clogged, which in turn put too much strain on the fuel pump and poped the relay.

but my question is. my horn still works. so how did i fix it. do relays reset themselves after you unplug them? and do you think it's my fuel filter? if not please shed some light on this for me. THANKS for taking the time to read all of this.

Viper

 

[budwich]

You potentially have a few things at play. First, as you found out, for sure if you don't hear your fuel pump turning on, the engine isn't going to be "happy".... swapping out the relay appears to have helped in that regard. Your conjecture that your fuel filter is a problem may also be a "contributor" to your problem. Of course, changing out the fuel filter should also help alleviate that potential issue. However, as you noted that the changed relay still worked in the horn circuit. Quite probable and it is likely that the relay unto itself isn't the problem. You can swap the relay back in and it is likely that your fuel pump will still function (no it didn't "heal" itself). The actual circuit relies on both the contacts thru the relay and the windings in the pump. It is possible that the contacts are not making a good enough connection (too resistive) such that the windings aren't getting their "full share of juice" to make the pump function. It is likely that your pump is "marginal" and along with other circuit "marginality", fails to function at capacity. You can change out some of the easier components (ie. the relay, the filter) and see if that helps. You can test your fuel pressure to see if you are getting sufficient pressure. This test will give you the best indication of a fuel delivery problem that will then probably point to your pump.

 

[aldive]

I would do the following:

(1) swap out the fuel filter
(2) check the fuel pressure

Good luck .......

 

[Viper81]

I also used the search and found this other thread that said: if a fuel pump has a high pitched buzz to it then it is healthy, but if it's a low pitched tone than it's going bad. can anyone confirm or deny this theory?

mine (after i switched the relays) is a high pitched buzz. didn't really pay much attention before this problem so i have nothing to compare it to...

also is there anywhere that can do a free pressure test or something that you know of? or you could tell me how to do one myself.

Thanks

Viper

 

[cruize2000]

Exact same thing happened to me. I swapped out the relays...they all worked fine. Ended up having to change the fuel pump. :fire: It's not too bad of a job as long as you buy the repair manual and a fuel line disconnect tool. My main problem was that my fuel tank was completely full when my fuel pump went out so I had to siphen the entire tank to make it easier. Completed the job in about 4 hours (after I emptied the fuel tank). Good luck to you.

 

[marragtop]

Did you by any chance disconnect the battery? If so, it may run rough for the first mile or 2 while the computer resets. Just a thought..

 

[JayTye4k]

I am currently having the same problem with my 96 explorer. It doesn't start all the time and it's getting worse. Sometimes I hear the pump turn on and other times I don't hear it at all. I just paid 410.00 to have the egr valve replaced along with a few sensors. I have a smoother idle while driving but I am still having the starting problem. It didn't give any codes for the fuel pump so I'm at a loss of what to do here. Any follow ups on this thread would be appreciated.

 

[budwich]

The fuel pump won't usually throw any codes. If your pump isn't starting on occassion and you have changing out the relay, you probably have a marginal pump where the overall circuit resistance is too resulting in insufficient starting current to cause the motor to start...... much like a poor starter on your truck when it just goes "click" even with a good battery. In these cases, the pump will likely show "reasonable" pressure when running however, it will find a position such that the armature will not turn / start.

 

[BrooklynBay]

If there is no CEL, then the PCM isn't getting any power. If it gets no power, the fuel pump will not get any power either. Check the ground connection near the battery. The fuel pump, PCM, or horn will not start without a relay. The wrong relay was probably pulled out. Maybe it was the relay for the A/C clutch, or something else. There are at least 4 relays under the hood in that area, so they are easy to mix up. Check AutoZone's website for a schematic.

 

[Viper81]

ok, today i pulled out the battery and took it up to autozone and had it checked. He said it was a good battery BUT it appears someone tried to put the negative terminal on with a hammer and smashed it in alittle. when we tilted it sideways battery acid started pouring out. LOL. Not really funny but i had to get a new battery cuz that's not good. also i cleaned the terminals very well becuase there was battery acid all over them.

that probably(sp.) had something to do with power not getting to the fuel pump and PCM.

but so far since that day it has started right up. no problems. very weird.

Viper

 

[BrooklynBay]

Did anybody work on your vehicle recently? Maybe they disconnected the battery to work on it, and messed it up.

 

[Viper81]

no, i noticed it was like that shortly after i bought it about 1 year ago and it hasn't cause any problems so i left it alone till i got enough money to get a new battery. but when i took of the terminals i noticed that they were sort of corrroded(sp.) so i cleaned them good with a wire brush.

Viper