Fuel Problem.
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Fuel Problem.
We have a automatic 1989 bronco with a 5.0L. First we had the problem of it not starting at random times. We check the fuel pressure and it was low. Changed the fuel filter and that didn't change much. At this point we went ahead and changed out both fuel pumps and, the tank cause we it was rusty. This seemed to fix the problem but then it started acting up again. So, we figured we might as well change the regulator, nothing.
At this point we didn't what the heck was going on. Then we realized that the pump wasn't kicking on right away like its supposed to, when you turn the key forward. So, we replaced the relay. That didn't make a differnce either.
We did figure out that you have to wait until you hear the fuel pump kicks on before you start it. This can take up to a minute or two.
What do you guys think?
At this point we didn't what the heck was going on. Then we realized that the pump wasn't kicking on right away like its supposed to, when you turn the key forward. So, we replaced the relay. That didn't make a differnce either.
We did figure out that you have to wait until you hear the fuel pump kicks on before you start it. This can take up to a minute or two.
What do you guys think?
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Do a search on here for doing a test on the fuel pumps using your self test port and see if they run. If not you may need to replace the frame mounted fuel pump. Also check your power wire from the relay to the inertia switch and from the inertia switch to the frame mounted fuel pump. Ford wrapped this wire up and over the dash frame where its sharp on my 1988. I ended up rewiring from the relay to the main fuel pump. The main fuel pump should turn on for 1 second after you turn the key on. It should not take one minute. Also since you had rust in your fuel tanks did you correct this? if not be sure to remove the rust and check your fuel filter also. Let us know how it turns out for you. PS: do a search on my name and look where Subford posted. He posted a bunch of wiring schematics for my 1988-89 vehicle
BigLar
BigLar
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We replaced the tank and the filter at the same time.(turned out not to be rusty on the inside) The pump on the rail was also replaced.
If I have enough time today I'll do the pump test and see if it comes on right away or not. That should tell me if the new relay is also bad or if we have some type of wiring issue.
I'll take a look at those schematics.
Where is the inertia switch located on these? Is it the red botton under the driver's dash?
Thanks.
If I have enough time today I'll do the pump test and see if it comes on right away or not. That should tell me if the new relay is also bad or if we have some type of wiring issue.
I'll take a look at those schematics.
Where is the inertia switch located on these? Is it the red botton under the driver's dash?
Thanks.
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yes its the red button switch under the dash on the drivers side. Be sure to check that power wire!!! it was the problem on my truck. Follow the power wire from the inertia switch to the main pump and youll see what i mean!!
biglar
biglar
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