Something wrong with fuel system.

Diesel truck computer says something is wrong with the fuel system. It could possible be an electrical problem.
Experienced mechanics share their insights in answering this question :
I would recommend you ask for help from a diesel mechanic with a diagnostic scanner. He will be able to see what fault codes are in the computer and that will give him starting point for diagnostics. This will help him determine what the problem is with your truck.

How to Identify and Fix Common car Problems ?

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This can affect the combustion process and cause the engine to sputter and lead to jerky power delivery. More often than not, this symptom is intermittent. That being said, everything mentioned above can also be symptoms of other fueling and electric issues, but usually, it`s suggestive of a bad fuel pump.
It usually means the vehicle is low on fuel, has contaminated fuel in the system or the fuel pump isn`t working correctly. A fuel system issue might also show itself when you are driving the car under stressful conditions (high temperatures, high altitude, steep uphill climbs, or carrying an uphill load).
Allegedly, the fuel injection pump in affected vehicles appears to have a fragile and unstable design that allows metal components to rub against each other. The metal shavings this produces can contaminate the fuel system in affected vehicles, which can result in premature wear and engine failure.
The symptoms of a cam or lifter failure usually involve a chirping, ticking, squealing or squeaking sound accompanied by a Check Engine light and engine misfire codes stored in memory. The misfire condition may not be evident to the vehicle operator.
Fuel pump failures can be caused by electrical faults, old age (wear) or fuel contaminants (dirt, moisture or bad gas). Fuel pump failures often occur without warning. Fuel pumps, injectors and pressure regulators are the three most commonly replaced fuel system components.
The most common reason a pump fails is wear on the pump from improper lubrication or over-use. The best way to explain a failed fuel pump due to wear and tear is to explain what other reasons may have lead to a failed pump: Most fuel pumps are lubricated by the fuel in the tank itself.
Fuel replacement costs these days can range anywhere from $390 to $900 depending on the vehicle`s make, model, and age. Typically, repairs or replacements can cost between $220 and $1062. For just the pump itself, you`re looking at a cost between $200 and $800.
The typical cost for a fuel pump replacement is around $900 to $1,100, depending on the vehicle, its age, and your region. Labor costs range from about $500 to $600, and parts for fuel pump replacement are about $400 to $500. Estimates do not include taxes and fees.
The Easy Fuel capless fuel filler feature eliminates the need for a fuel filler cap and allows you to simply insert the fuel nozzle. When fueling is completed, removing the nozzle causes the spring-loaded fuel filler to close and latch.
Can You Drive With A Bad Fuel Rail Pressure Sensor? A bad fuel rail pressure sensor could still work, albeit inefficiently. In most cases, it won`t leave you on the side of the road. However, symptoms of a faulty unit will likely get worse with time to the point where you won`t be able to drive your car.
One of the first signs of a failing fuel rail pressure sensor is poor fuel economy. If your car suddenly seems like it`s using more gas than usual, it could be due to a problem with the sensor. Additionally, if your car starts to hesitate or stall when accelerating, this could also be a sign of a failing sensor.
Common signs include the Check Engine Light coming on, the car not feeling right when running, and issues with starting the car.
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. You can also check your car`s fuse box; a blown fuel pump fuse is another reliable symptom of a failed pump.
The most common cause of fuel pump failure is frequently running the tank low on fuel, which causes the motor to overheat. The second most common cause is fuel contamination, usually dirt and rust particles that clog the fuel strainer and prevent the pump from drawing enough fuel under high engine load.
After 100,000 miles, the failure of the pump is likely enough that if you are replacing a major part in the fuel system nearby, it may be advantageous to replace it at the same time.
A failing/failed fuel pump will cause major performance and drivability issues with your vehicle. If your fuel to air ratio is off and the cylinders aren`t getting enough fuel, then the pistons aren`t firing and your engine is struggling to move the vehicle forward.
Surging Engine

The flipside to not enough fuel is too much fuel and a fuel pump that is going out can send too much fuel to your engine, too. You`ll notice your engine surging when this happens and the surges can make driving dangerous. Surges mean the vehicle picks up and then drops speed. Not good on the road.

Car stutters and stumbles—the first sign of a bad fuel pump is intermittent coughing and sputtering that can`t be explained. If you`re sharp, you`ll fix the problem at this stage before it gets worse. Excessive whine from the fuel pump—modern electric fuel pumps will get noisy before failing.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

I have a 1981 e-350 with dual fuel tanks the p.o. added a third tank and 3 electric fuel pumps along with sepparate gauges and swi
ANSWER : The switch you are referring to is vended with the required electrical and fuel schematic (I just looked in the box) that answers your installation question. If you want an advance view, here is a link as well. Yes, you need a return line and just refer to the aforementioned link. If you are retrofitting back to OEM, I strongly encourage you to buy the original Factory Service Manual (FSM). There are lots of details attending this system and obviously it is difficult to recount it all here. The FSM will make your life much easier and you can then make sure your installation is perfect. Alternatively, YourMechanic can dispatch a certified mechanic and perform the whole retrofit and check out if you desire. Just request and schedule a generic service such as fuel pump service and the mechanic will come to your location and estimate the parts and labor required. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Fuel pressure
ANSWER : Hello,
You may want to try checking the fuel pump relay. The relay wires should have ground on two wires, power on one wire and switched power on another wire. To activate the fuel pump your ECU actually connects one of the ground wires to complete the circuit and send power to the fuel pump. If the wires all have power running through them, then it is likely you have a faulty relay. The wire coming from the fuel pump is the other ground wire. I would recommend having an expert from YourMechanic come to your location to diagnose your wiring as this can be very difficult and time consuming without the proper wiring diagram.

Just replaced my fuel pump but its not getting any power tested fuel pump relay and fuel fuse both good tested the wires all good.
ANSWER : You need to look at the theft light on dash to make sure it comes on and goes off when you turn the key to the on position. If light comes on and stays on then your theft system is causing the fuel pump to not be engaged. I recommend you check the theft system and then scan the computer for theft system codes. You may need to reprogram the keys to work or you have an bad sensor for the ignition key in the steering column.

the car is acting like its getting to much fuel. changed the fuel pump, fuel filter, and the fuel pump relay.
ANSWER : There could be a few things contributing to your problem. You are correct that clogged or sticking fuel injectors and possibly the fuel pressure regulator could be faulty. A plugged catalytic converter can also cause the vehicle to bog down. A failing throttle position sensor can cause the symptoms you describe as well. I suggest having a certified technician, like one from YourMechanic.com, do a few tests to determine the exact cause of your starting concern.

Fuel Rail System Error Code
ANSWER : Considering that the code is related to a problem in the fuel system, you should leave it to the professionals to avoid personal injury. When fueling the car, check twice to make sure the fuel cap is fastened properly. Low fuel pressure from a clogged filter can hinder the performance of the pump and damage it in extreme cases. You may want to have a second technician inspect the loss of power and hesitation to get a second opinion on the car before following through with the repair. If you would like this checked, a technician from YourMechanic can come to your location to diagnose the cause of the Check Engine Light and assess the needed repairs.

I have a truck that won’t run and is not getting gas to the engine. Fuel pump is running, have a new filter and new fuel pressure
ANSWER : Hi There,
It sounds like you may have a clogged fuel injector or potentially a faulty injector that is fried internally. I would suggest testing them if you have access to a multi meter. Disconnect the injector from the electrical connector and set your multi meter to Ohms mode and measure the resistance of the injector. After testing all injectors, compare the resistance. They should be the same or very close. If they are not, they will likely need to be replaced.

Installed new delphi fuel pump and fram fuel filter. still no pressure on fuel rail valve and wont start. 2003 Chevrolet Tahoe
ANSWER : Hi there – I suspect you have weak power getting to the fuel pump. I would first check the voltage coming out of the fuel pump relay. If the contacts in the relay are burned, you will not get reliable current flow to the pump. Check the fuel pump ground as well (voltage drop across the ground, not just continuity). I recommend a fuel system inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

How long and what is the process to replace a fuel pressure sensor?
ANSWER : A professional mechanic would require roughly 5 hours. (If just the regulator is replaced that takes about 1 hour). Some parts, as noted below, cannot be re-used, you need a precision inch pound torque wrench, FSM instructions (and TSB updates if applicable; procedure was changed in 2007 for instance) and the system has to be bled when done.

Below is partial list of steps, copied and pasted directly from the service manual:

1. Disconnect battery and put protective material in front of the charge air cooler (CAC) or damage to the CAC may occur.

2. Remove air cleaner assembly.

3. Disconnect the oil drain tube from the crankcase vent oil separator.

4. Loosen the air cleaner outlet tube clamp and detach the air cleaner outlet tube from the turbocharger.

5. Remove the bolts, the crankcase vent oil separator and the air cleaner outlet pipe as an assembly.

6. Remove and discard the crankcase vent oil separator press-in-place gasket. (To re-install, tighten to 13 Nm (115 lb-in).

7. Disconnect the PCM electrical connector (BE SURE BATTERY IS DISCONNECTED FIRST!) and retainer. Disconnect the in-line electrical connector and position the engine wiring harness on the engine.

8. Remove the pushnuts and the glow plug module heat shield.

9. Disconnect the high-pressure fuel injection pump electrical connector and detach the retainer from the glow plug module bracket. Disconnect the glow plug module and the exhaust gas recirculation temperature (EGRT) sensor electrical connectors, detach the wiring retainer and position the wiring harnesses aside.

10. Remove the nut and position the ground strap aside. To install, tighten to 13 Nm (115 lb-in).

11. Remove the engine wiring harness bolt. To install, tighten to 13 Nm (115 lb-in).

12. Remove the heater supply tube nut. To install, tighten to 13 Nm (115 lb-in).

13. Remove the bolts and the glow plug module bracket. To install, tighten to 13 Nm (115 lb-in).

14. Remove the nut and position the transmission fluid indicator tube aside. To install, tighten to 8 Nm (71 lb-in).

Warning: Do NOT disconnect the glow plug electrical connector before dislodging the seal from the valve cover or the wiring harness may be damaged.

15. Using an appropriate tool, dislodge the glow plug wiring harness seals from the valve cover.

16. Disconnect the glow plug electrical connectors by pulling on the glow plug wiring harness tee above the seal. Remove the glow plug wiring harness.

17. Remove the nut and position the crankcase ventilation drain tube aside.

18. Disconnect the wiring harness retainer from the valve cover stud.

19. Disconnect the wiring harness retainer from the generator bracket.

20. Disconnect the A/C pressure switch electrical connector. Position the harness aside.

Warning: Do not bend or flex the heater supply tube or damage to the tube may occur.

21. Remove the stud bolts, bolts and the valve cover. Remove and discard the valve cover gasket. To install, tighten to 9 Nm (80 lb-in).

Warning: Contact with exposed fuel injector wiring, if energized, may result in electric shock.

Use care when working on or around energized fuel injector wiring. Fuel injector wiring supplies HIGH VOLTAGE to operate the fuel injectors of course, you disconnected the battery though.

22. Disconnect the fuel rail pressure (FRP) sensor electrical connector.

Warning: Fuel injection equipment is manufactured to VERY precise tolerances and fine clearances (think space shuttle). To prevent fuel system damage, it is essential that absolute cleanliness is observed when working with these components. Always install fuel system caps on any open orifices or tubes.

23. Remove the FRP sensor. To install, tighten the FRP sensor in 2 stages.

Stage 1: Tighten to 7 Nm (62 lb-in).
Stage 2: Tighten an additional 40 degrees.

24. Bleed the high-pressure fuel system.

If you feel like this job may be too overwhelming or run into any issues, consider YourMechanic to get it done. One of our mobile technicians can come to your home and replace the fuel pressure sensor at your own convenience.