Why does my fuel pump only run for a few seconds?
This sound is the electric fuel pump trying to prime the fuel system. It will only run for a few seconds and then shut off. If you are not sure you could hear it or if there is noise outside; you may have to try it several times. Turn the key on and wait then turn it off.
What to do if your fuel pump relay is failing?
If your vehicle is displaying any of the symptoms above, or you suspect that your fuel pump relay is having an an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the component should be replaced.
What is the average rating of a fuel pump relay?
Average rating from 198 customers who received a Car is stalling Inspection. The fuel pump relay is an electronic component that is found on virtually all vehicles equipped with an internal combustion engine.
How does an electric fuel pump keep cool?
Electric fuel pumps run continuously with your engine, delivering high-pressure fuel to the fuel rail and injectors. Fuel pumps keep cool by staying submerged in fuel. If you make a habit of running your tank all the way to empty before filling up; your fuel pump will most likely die before its designed lifespan.
How to troubleshoot fuel pump in GM 4.3L?
Once the intake air duct is back on the throttle body, have your assistant, inside the vehicle, crank the engine. 1.) The engine will start momentarily and after a few seconds will die. 2.) The engine will only crank but not start at all. 3.) The engine will start and stay running. OK, let’s find out what your results mean:
What’s the fuel pressure on a 1996 Chevy k1500?
Alright guys im relying on someone to help me out here with the actual PER GM specs for the Vortec Fuel pressure. I have done alot of searching and know that anything over 55 etc is good however my buddys truck (1996 Chevy K1500 5.7L 4L60E) has a P0300 code and after alot of digging i checked the fuel pressure.
What happens if your fuel pump is failing?
The fuel pump feeds fuel to the engine at a reliable rate; without this pump, your fuel would just sit in your tank, useless and inert. If you’re attentive, you can catch the symptoms of a failing fuel pump and have it repaired or replaced before it leaves you stranded on the side of the road.
What’s the difference between a bad fuel pump and a PassLock failure?
Since there’s a good chance that the PassLock anti-theft system may have armed itself, take a look at this section: Difference Between A Bad Fuel Pump And An Anti-Theft System (PassLock) Failure. CASE 2: The engine did not start, not even momentarily.
What causes a car to not start with no gas?
Problem may be at wiring connector on top of fuel tank (hard to reach!). No gas in fuel tank (Check the fuel gauge, and keep in mind the gauge may not be reading accurately). Bad gas (Contaminated with water or too much alcohol or diesel fuel). If you just filled up with gas and now your car won’t start, suspect bad gas.
Why does my car have no fuel pressure?
Many people recognize this sound every time they start the car but don’t realize it is the fuel pump running. If you “DO NOT” hear the buzz of the fuel pump; then your engine has no fuel pressure, and we need to see why. The first thing you want to do is check the fuse panel to see if the fuse is blown.
Where to check for no start fuel pump?
The first thing you want to do is check the fuse panel to see if the fuse is blown. If your car has two fuse panels than the one in the engine compartment; should be the correct one to check. The fuse panel or circuit box is usually located near the battery; and is a small black box with a removable lid.
Why does my fuel pump not start when I change it?
You always want to replace the fuel filter when replacing the fuel pump. This could cause the concern you are having. It may seem as you are getting enough fuel from the pressure regulator but if the pressure from the fuel tank is not correct, it will still not start. Another problem you could be having is spark.
Problem may be at wiring connector on top of fuel tank (hard to reach!). No gas in fuel tank (Check the fuel gauge, and keep in mind the gauge may not be reading accurately). Bad gas (Contaminated with water or too much alcohol or diesel fuel). If you just filled up with gas and now your car won’t start, suspect bad gas.
Many people recognize this sound every time they start the car but don’t realize it is the fuel pump running. If you “DO NOT” hear the buzz of the fuel pump; then your engine has no fuel pressure, and we need to see why. The first thing you want to do is check the fuse panel to see if the fuse is blown.
Is there a way to turn on the fuel pump?
There’s no way you have no signal, but then starting the truck by adding fuel will then turn on the injectors and pump. That’s just crazy. Good luck with that one. Once the truck starts and is running you can remove the jumper to the fuel pump and it will continue to run.
Can a fuel pump run if the ECU is not on?
Click to expand… It would be a good idea to check the wiring since you yanked on it. But if the pump is running thats all that matters at this point. The ECU doesn’t control fuel pressure so it’s not like you tripped some kind of electronic relief valve.
What should fuel pressure be when no Buzz?
Fuel pressure is typically in the 35 to 45 psi range. If your Anti-Theft light is flashing; the anti-theft system is disabling the fuel pump to prevent the engine from starting. Bad fuel pump (Pump should run for a few seconds when ignition key is turned to start, no buzz means no fuel delivery to the engine).
Click to expand… It would be a good idea to check the wiring since you yanked on it. But if the pump is running thats all that matters at this point. The ECU doesn’t control fuel pressure so it’s not like you tripped some kind of electronic relief valve.
What causes the fuel pump to not start?
The fuel pump is running and delivering normal pressure to the engine But, with all that working your engine still will not start. So, the most likely cause, is that the fuel injectors are probably not opening. The (PCM) uses the trigger signal from the crankshaft position sensor; and/or camshaft position sensor to pulse the injectors.
What are the symptoms of a bad fuel pump?
Also, the symptoms are almost exactly the same as bad/clogged fuel filter. Here are the most common symptoms of a bad fuel pump in your Jeep Wrangler: One of the most common signs that a fuel pump is going bad is a whining sound. The whining sound can indicate that the fuel pump is going out before there are any performance based issues.
Can a wrangler run without a fuel pump?
Without gas your Wrangler will not run at all. With that in mind, most of the symptoms of a bad fuel pump revolve around the vehicle stalling out or not running at all. In modern fuel injected vehicles, the fuel pump sits right in the fuel tank and “pushes” the gasoline to the fuel rail (s).
What are the symptoms of a faulty fuel pump relay?
1 Engine does not start. A common symptom of a faulty fuel pump relay is an engine that just refuses to start, even though the engine may still crank when the 2 Engine stalls. One of the most common symptoms of a failing fuel pump relay is an engine that suddenly stalls. 3 Loss of Power. 4 No noise from the fuel pump. …
Why does my fuel pump make a buzzing noise?
The buzzing sound you are listening for sounds like an electric motor running. This sound is the electric fuel pump trying to prime the fuel system. It will only run for a few seconds and then shut off. If you are not sure you could hear it or if there is noise outside; you may have to try it several times.
What makes a walboro 255 fuel pump run?
Rewired walboro 255 fuel pump and Aeromotive fpr and aftermarket fuel lines. When did this happen? Car was running strong, shut off motor and 10 minutes later started it up again, sputtered and slowly died.
Why does my fuel pump make a whining noise?
A whining fuel pump may also be a sign that other parts of the car are damaged. If a hose that transfers fuel to the engine or carburetor is damaged, it will release air into the fuel system and reduce the pumping pressure, resulting in the noise.
What to do if your fuel pump is not working?
If nothing after that, then the fuel pressure regulator is not working and needs replacing. If you get pressure to the rail, then there could be a problem with the injectors; they may be either dirty or plugged up. Take the injectors off the engine and clean them with CLR.
How does the fuel pump work in a car?
The fuel pump is a device that moves fuel from your tank to the engine, supplying the fuel at a constant pressure to ensure that your engine runs smoothly.
1 Engine does not start. A common symptom of a faulty fuel pump relay is an engine that just refuses to start, even though the engine may still crank when the 2 Engine stalls. One of the most common symptoms of a failing fuel pump relay is an engine that suddenly stalls. 3 Loss of Power. 4 No noise from the fuel pump.
What are the odds of having a bad fuel pump?
For example, the odds of having a bad fuel pump and a bad crank sensor at the exact same time are astronomical.
What to do if your car wont start after replacing the fuel pump?
Car won’t start even after I replaced the fuel pump. Car won’t start and turned off while driving. Replaced the fuel pump and I can hear it working. The car still won’t start.
What happens when the fuel pump relay goes bad?
If the fuel pump relay suddenly fails, it will light up the check engine light and store a trouble code on the fuel pressure. The fuel pump relay going bad can affect the fuel pump’s power and affect fuel delivery to the engine.
What to do if your Nissan Sentra won’t start?
You need to check the fuel inertia switch in the right passenger kick panel to make sure it is not tripped. If not tripped, then check that the pink wire in and out has power when you crank the engine…. The 2015 Nissan Sentra is equipped with a CVT transmission.
Why does my fuel pump make a whirring noise?
When you turn the ignition on in the ignition lock, you should hear a whirring noise from the rear of the car. This means that the fuel pump started building fuel pressure in the fuel rail. If you cant hear this, there might be a problem with the fuel pump relay.
What should the pressure be on an electric fuel pump?
Electric fuel pumps on electronically controlled fuel injection systems need to produce enough “high” pressure to allow the injectors to produce a sufficient spray of atomized fuel into the intake path (or into the combustion chamber in a direct-injection system). Fuel pressure is typically in the 35 to 45 psi range.
Why does my Mercedes 560sl have trouble starting?
A 1988 Mercedes 560SL has trouble starting despite efforts to crank the engine. Could the fuel filter or pump be responsible for this? Check the fuel pumps to see if they are working alright.
Why is my fuel pump not working properly?
If the pumps are operational and the tank has fuel in it, the problem might lie with the ignition and have to do with either the crankshaft sensor, ignition module/coil or the cap and rotor. In case the pumps are not working properly, the problem could be caused by a faulty fuel pump relay.
What kind of engine does the Mercedes 560sl have?
Questions about Mercedes 560SL Issues on JustAnswer The Mercedes 560SL is part of the popular 107 SL line of sporty coupes and convertibles that came out from 1971 to 1989. It was fitted with an overhead camshaft 5.6-liter V8 engine that used Bosch fuel injection and produced 238 horsepower and 287 foot-pounds of torque.
The first thing you want to do is check the fuse panel to see if the fuse is blown. If your car has two fuse panels than the one in the engine compartment; should be the correct one to check. The fuse panel or circuit box is usually located near the battery; and is a small black box with a removable lid.
How to diagnose a faulty fuel pump failure?
In this video we go over the basic steps of diagnosing a faulty fuel pump. So if your vehicle isn’t starting and you suspect a fuel pump problem, here are some steps to follow to confirm your suspicions. Another ‘quick’ test is to bang on the fuel tank and then try and start the engine.
Why is my fuel pressure not at specification?
The usual suspect behind this is the fuel pump. The fuel pump test should be conducted with a fuel pressure gauge, so that you can get an accurate result you can trust (any other method may have you wasting time and money on a fuel pump your vehicle does not need). CASE 1: Fuel pressure is at specification.
What does it mean when your fuel pump is not working?
CASE 2: Fuel pressure IS NOT present. This usually means that the pump has failed, but not always. Before condemning the fuel pump as bad, you need to make sure that the fuel pump inertia switch has not tripped and therefore blocking power from reaching the fuel pump.
The usual suspect behind this is the fuel pump. The fuel pump test should be conducted with a fuel pressure gauge, so that you can get an accurate result you can trust (any other method may have you wasting time and money on a fuel pump your vehicle does not need). CASE 1: Fuel pressure is at specification.
How can I check for no fuel pressure?
After verifying that no fuel pressure exists, check that the fuel pump is getting power (12 Volts). This can be done by tapping into the power circuit that feeds the pump with 12 Volts with a multimeter (but without dropping the fuel tank to remove the fuel pump).
Can a fuel pump be replaced with no voltage?
If your multimeter registers 12 Volts, you cam replace the fuel pump with confidence, since this confirms the fuel pump as bad. If no voltage is present, as your helper cranks the engine, then the fuel pump should not be replaced. You need to find the cause of these missing voltage.
How can I get my fuel pump to run?
Swap an accessory fuse wuth the ignition fuse and give it a whirl. also if I use a “power probe” and apply battery voltage to the fuel pump fuse the fuel pump does run. thanks nipplesurfer, I did try that yesterday.
Why does my Harley Davidson have no fuel pump?
If battery static volts measure 11.6v or less with the ignition on the ECM won’t energize the system. am not getting any voltage at the 15 amp fuse at key on, also have battery charger on while testing. engine cranks at good speed. are there more powers and grounds at the battery then just the main positive and negative battery cables?
What causes a fuel pump to whine when you start the car?
A low fuel level can cause the engine to work much harder to build the necessary pressure to pump the fuel. To analyze the problem, start the car when the fuel is low (below one-fourth tank) and listen for the sound. If the whine is audible, fill the tank immediately. When you start the vehicle again, the whine should be reduced or absent.
How to eliminate spark problem from fuel problem?
Easy way to eliminate spark problem from fuel problem is to remove air filter and squirt some gas in intake while spinning starter. If it fires, you know it’s a fuel problem, not spark. Click to expand… Hello Breeze and thank you for educating me a bit more….
This sound is the electric fuel pump trying to prime the fuel system. It will only run for a few seconds and then shut off. If you are not sure you could hear it or if there is noise outside; you may have to try it several times. Turn the key on and wait then turn it off.
The ECM activates the fuel pump for several seconds after the ignition switch is turned on to improve engine startability. If the ECM receives a engine speed signal from the crankshaft position sensor (POS) and camshaft position sensor (PHASE), it knows that the engine is rotating, and causes the pump to operate.
How can I tell if my fuel pump relay is faulty?
2. Engine does not start. Another symptom of a faulty fuel pump relay is an engine that does not start. If the fuel pump relay fails the fuel pump will be left without power. The engine may still crank when the key is turned, however it will not be able to start due to lack of fuel.
The engine may still crank when the key is turned, however it will not be able to start due to lack of fuel. This symptom can also be caused by a wide variety of other issues, so having the vehicle properly diagnosed is highly recommended. 3. No noise from the fuel pump
What kind of noise does a fuel pump make?
No noise from the fuel pump. Another symptom that may hint at an issue with the fuel pump relay is no noise from the fuel pump when the key is switched on. Most fuel pumps will produce a low volume hum or whine which can be heard from the inside the vehicle if listened for closely, or from the outside of the vehicle, near the fuel tank.
What to do if you can’t hear your fuel pump?
If you can’t hear the pump working, enlist the help of an assistant and follow the next steps: Remove the fuel filler cap. Put your ear close to the fuel filler opening. Ask an assistant to turn the ignition key to the ON position, but don’t start the engine. You should hear a whirring sound coming from inside the fuel tank for about two seconds.
Why does my fuel pump not prime when I turn it on?
Pulled fuel pump relay and put in a jumper wire to run the fuel pump and it started. Put the fuel pump relay back in and it starts and drives, but the fuel pump still doesn’t prime when turning the key on. I’m afraid that after sitting overnight, it will once again refuse to start.
What does no start, no fuel pump mean?
Not sure if that is the problem though as that fuse may get power after a relay closes? fuse is good. Any other ideas? No start, no spark, no fuel pump. working on my 2008 screaming eagle ultra classic that I just got. Engine is a no start.
What happens when a fuel pump relay goes bad?
If the fuel pump relay has an issue while the vehicle is operating it will cut off power to the fuel pump, which will cause the engine to stall. A faulty relay may allow the vehicle to be restarted a short while later, while a completely failed relay will not.
When is it time to replace your fuel pump?
Like any device, however, fuel pumps can and do eventually wear out after thousands of miles of use. If your car struggles with weak or inconsistent power, it may be time to replace the fuel pump on your car. Have you ever had to deal with a failing fuel pump?
How can you tell if your fuel pump is dead?
Of course, there could be other explanations for your engine’s failure to start besides a failed fuel pump. To confirm that your pump has failed, check the pressure in your fuel lines with a fuel pressure gauge; if it reads zero, then your pump is likely dead.
What to do if your fuel pump won’t start?
Source: by miesk5 at Ford Bronco Zone Forums Got it started last with ether. Fuel pump still runs in key on not running. Relay good. Check engine light on when started. Can not perform KOEO test as long as that fuel pump runs yo, Now swap PCM relay for horn relay. And see if horn beeps or stays on.
How long does it take for fuel pump to shut off?
Not to mention it just adds more wear and tear to the starter motor and engine. This usually lasts around two or three seconds, unless the ignition key is turned to crank the position.
What makes the fuel pump run all the time?
Pump Runs w/Ignition Switch Off; The ign switch actuator and or switch needs to be adjusted. When the ignition sw is switched to the ON position, it turns the EEC Power Relay on. The EEC Power Relay provides power to the EEC-IV processor and the control side of the fuel pump relay.
Fuel pressure is typically in the 35 to 45 psi range. If your Anti-Theft light is flashing; the anti-theft system is disabling the fuel pump to prevent the engine from starting. Bad fuel pump (Pump should run for a few seconds when ignition key is turned to start, no buzz means no fuel delivery to the engine).
The fuel pump is a device that moves fuel from your tank to the engine, supplying the fuel at a constant pressure to ensure that your engine runs smoothly.
Can you verify you are getting spark after replacing fuel pump?
It may be a walboro but it is a 100% exact replacement, only way better so there should be no issues there. If you are sure you hear the fuel pump prime when the key is turned forward I would say you are not getting spark. Has a wire come loose? Can we verify you are getting spark?
What to do if your well pump won’t shut off?
If this happens, turn off the system and wait for the well to recover then turn the system on again. If this problem persists it is recommended that you install either a motor protection device to protect the pump and motor from burning up, or to install a flow restrictor to throttle the pumps discharge to below the production of the well.
Why does my water pump not shut off?
If you everything we just mentioned checks out and you are still experiencing low water pressure it may be a problem with the pump. Checking the amperage of the pump motor may help you to determine if the motor is drawing high amps it may be a badly worn pump a bound pump or clogged pump screen.
What should I do if my fuel pump is not working?
Fuel pump breakers usually have a button on top that pops up when it trips. Simply push this button back in until it clicks. Check the owner’s manual for the exact location. Fuel Pump Testing – If the fuse is good and the circuit breaker is not tripped; then the engine is not getting fuel pressure.
Why does my fuel pump run hot when I shut off the engine?
This is due to the fact that when you shut off the engine with a low fuel level; the fuel can drain from the priming chamber designed into the fuel delivery system. So when you restart your car, the pump runs hot and un-primed until it can refill the fuel chamber. Over time this will burn out the pump motor.
What should you never do while pumping gas?
Never smoke around the gas pump. And this should be obvious, but never ignite lighters or light matches anywhere near a gas pump. If you have this smoke detector, you should replace it immediately. If you do experience a fire when refueling, back away from the vehicle.
If this happens, turn off the system and wait for the well to recover then turn the system on again. If this problem persists it is recommended that you install either a motor protection device to protect the pump and motor from burning up, or to install a flow restrictor to throttle the pumps discharge to below the production of the well.
Why does my Car Crank but not get fuel?
IT WILL NOT GET FUEL IN THEFT MODE , WHICH IS WHY YOH GET THE CRANK BUT NO START!!! unfortunately your car either forgot the key , or the key itself took some damage either way just have it relearn the key , put it in the on position , and leave it for 15 mins or so or get a new key and have it programmed , YW Was this answer helpful?
Why does my fuel pump not prime with the key on?
Fuel pump doesn’t prime with key on. I’ve been trying to figure this out for a couple days now. My 01 Tiburon wouldn’t start the other day. It would crank, but wouldn’t fire. When I turn the key to the “on” position, the fuel pump doesn’t kick on.
When is the fuel pump relay turned on?
The fuel pump relay is an important component of the fuel system of your vehicle. The fuel pump relay gives the fuel pump power when it is time to build up fuel pressure in the rail. Whenever you turn on the ignition of your vehicle, the fuel pump relay is turned on. There are different reasons due to which the fuel pump relay fails.
Fuel pump doesn’t prime with key on. I’ve been trying to figure this out for a couple days now. My 01 Tiburon wouldn’t start the other day. It would crank, but wouldn’t fire. When I turn the key to the “on” position, the fuel pump doesn’t kick on.
The fuel pump relay is an important component of the fuel system of your vehicle. The fuel pump relay gives the fuel pump power when it is time to build up fuel pressure in the rail. Whenever you turn on the ignition of your vehicle, the fuel pump relay is turned on. There are different reasons due to which the fuel pump relay fails.
Why is the fuel pump relay not closing?
If jumping the fuel pump relay makes the pump run, and if the relay tests good. Then you need to determine why the ECM is not telling the relay to close. Start by testing continuity back to the ECM. Here is the electrical diagram for the 01 Tib Fuel Pump Relay
If jumping the fuel pump relay makes the pump run, and if the relay tests good. Then you need to determine why the ECM is not telling the relay to close. Start by testing continuity back to the ECM. Here is the electrical diagram for the 01 Tib Fuel Pump Relay
Why does my car not start when I Turn on the ignition?
Listen to hear the fuel pump buzz for a few seconds as you turn the ignition to the “on” position. If no buzz is heard from inside the car or back by the fuel tank, the pump may be dead and fuel is not reaching the engine at all. Note that some fuel pumps only flow while the car is cranking so some cars don’t have an audible buzz.
Why does my car have no buzz when I crank the engine?
If no buzz is heard from inside the car or back by the fuel tank, the pump may be dead and fuel is not reaching the engine at all. Note that some fuel pumps only flow while the car is cranking so some cars don’t have an audible buzz. Consult the internet or your owner’s manual for more information for your specific model.
Why is the fuel pump not turning on?
The pressure of fuel entering the engine from the fuel tank gets impeded in case of a plugged fuel filter. In such circumstances, the engine does not receive the fuel required to start and you get an impression that the fuel pump is not turning on.
Why does my car not start when there is no fuel?
When that happens, you get into your car and try to start the engine when it has NO fuel pressure. Since the battery is low on charge at a time when the engine needs even more power, you drain the battery trying to start with no fuel. By the time the fuel pressure builds, the battery may be so low that it can’t crank the engine fast enough to fire.
The buzzing sound you are listening for sounds like an electric motor running. This sound is the electric fuel pump trying to prime the fuel system. It will only run for a few seconds and then shut off. If you are not sure you could hear it or if there is noise outside; you may have to try it several times.
Why does my Car Crank and not start?
There are many reasons for your car to crank and not start. Anything from factory security system locking you out, bad fuse/relay, clogged fuel filter,faulty fuel pump, oil sending unit/crank sensor failure, clogged catalytic converter, failing electronic ignition, ECM/PCM,etc.,etc.
Where is the fuel pump relay on a Pontiac Grand Am?
The fuel pump relay is #18 in the fuse box. Start with the car off, and have somebody else put the key in the cars ignition and attempt to start the car while you listen to the relay. If you can hear this relay make a “clicking” noise as the car attempts to start, then it is working properly.
What happens when the fuel pump goes out on a Pontiac Sunfire?
There are physical signs that you can feel when your Sunfire’s fuel pump is going out. Before taking anything apart, check to see if your engine’s computer has any trouble codes saved in it. The engine may throw a P0087 trouble code. This trouble code detects that the fuel rail/system pressure is too low.
When to know if your fuel pump is bad?
If your car isn’t starting at all, and you hear the fuel pump prime that is usually a good indication that the pump is working to some capacity. Testing your Sunfire’s fuel pressure on each side of the pump would be the best way to diagnose this problem.
Why is the fuel pump in the fuel tank?
It is in the fuel tank because “pushing” fuel to the fuel rail is easier than “pulling” the fuel, which is what an inline pump would do. While being in the fuel tank makes the pump more reliable, it also makes it a lot more difficult to get to.
You need to check the fuel inertia switch in the right passenger kick panel to make sure it is not tripped. If not tripped, then check that the pink wire in and out has power when you crank the engine…. The 2015 Nissan Sentra is equipped with a CVT transmission.
Why does my Chevy Spark Plug not start?
Chevrolets have a common issue with fuel filters getting clogged. You always want to replace the fuel filter when replacing the fuel pump. This could cause the concern you are having. It may seem as you are getting enough fuel from the pressure regulator but if the pressure from the fuel tank is not correct, it will still not start.
What happens when fuel pump does not start?
The pump will trigger on the start circuit and run for about 15 seconds. If it does not sense oil pressure it will quit.
How can I tell if my fuel pump is cranking?
Get under the truck and see if you can figure which wire powers the pump and check it with a volt meter or a test light to see if it is getting power key on and also cranking. while you are under there check the pump circuit ground because I recall them being down where they get bombarded with whatever might be on the road surface and corrode up.
Chevrolets have a common issue with fuel filters getting clogged. You always want to replace the fuel filter when replacing the fuel pump. This could cause the concern you are having. It may seem as you are getting enough fuel from the pressure regulator but if the pressure from the fuel tank is not correct, it will still not start.
What should I do if my Mercedes Benz won’t start?
Start the car and you should be able to get around 60 psi. When the engine is running and when you turn off the engine the pressure should stay steady. Always perform this test on a cold engine. Next, make sure that the fuel injector connections are secure and not loose. Check the fuel pump and the fuel pump relay.
How does the fuel pump work on a Ford truck?
On late model Fords, there is a fuel pressure sensor but not on your truck. The PCM keeps the fuel pump relay energized for a second or two while the engine is cranking, then cuts it off the relay the engine does not start. If the engine starts, it keeps energizing the relay to run the pump.