Fuel supply related to engine misfire?

Recently replaced fuel pump and filter. Had gas tank cleaned out. Car misfires when idling and after a few minutes of running dies like the fuel is being cut off. Any suggestions? Check engine light is on too.

My car has 165000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Engine misfires can be caused by a list of problems, but there are a few suspects that occur more than others. Generally, misfires are caused by either a spark or fuel issue or in cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition modules not working properly. When the misfire results from a fuel related issue, this is commonly related to a lean fuel condition (lack of sufficient fuel supply to the motor). Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass air flow sensor, a faulty or dirty idle air control valve or a vacuum or intake leak. When the fuel supplied to the combustion chamber is insufficient, this results in an ignition (spark) that is igniting a less than balanced load of fuel and air. This results in a misfire or an explosion in the cylinder that is much less powerful than the other cylinders. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. I would recommend having an expert from YourMechanic come to your location to diagnose your misfiring problem.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Decreased Fuel Pressure

Low fuel pressure can lead to engine misfires, low acceleration, rough idles, and engine stalls. If your check engine light is on and your car has been stalling out, you may have a fuel pump failure.

Check fuel pressure: Low fuel pressure can cause intermittent misfires on multiple cylinders.
Fuel-related misfires can be caused by too little fuel. Fuel-related misfires can be caused by incorrect atomization of the fuel by the injector.
An imbalance in the air-fuel ratio or lean misfire, as it is also called, can cause your car to misfire. You will feel the misfire more when the car is idling as opposed to when the engine picks up speed and the car is running. Successful combustion requires the fuel ratio to be higher compared to the air mix.
The fuel pump is driven by a signal that changes the power to control the speed of the motor and pressure delivered to the fuel rail during the duty cycle.
If a clogged fuel injector continually struggles to disperse fuel to the engine, a time will come when it misses the fuel supply completely and the engine will misfire. The misfire will easily be felt while driving, and often requires immediate repair by trained automotive repair specialists.
Good quality fuel injectors rarely cause misfires whereas, poor quality or faulty injectors cause destructive misfires. The vehicle can experience various misfires when a faulty injector is a reason; it can lead to a loss in acceleration, power, and reduction in fuel efficiency.
Causes of lean misfire that only affect one cylinder include a dirty fuel injector, an open or shorted fuel injector, or a problem in the fuel injector driver circuit (wiring or PCM). Compression problems that may cause a misfire include a burned exhaust valve, bent intake or exhaust valve, or leaky head gasket.
Yes. While the damage may seem small initially, the longer you drive with a bad oxygen sensor, the worse the damage will become. Eventually, you may experience rough idling, poor acceleration, engine misfires, an illuminated check engine light, and failed emission tests.
Misfire at Idle Only. Your car may drive perfectly fine but display signs of little hiccups or small misfires at idle. Generally, the cause of a misfire at idle is an incorrect air-fuel mixture. This can be caused by a faulty O2 sensor, a fuel injector that needs cleaning, or even vacuum leaks.
The misfire can be caused by a worn spark plug, defective coil, faulty spark plug wire, faulty injector, plugged injector (each injector has its own miniature internal filter), mechanical valve fault and so forth. The most common issue is the spark plug is simply worn out or defective.
In a modern car, all of the engine management devices (such as the air flow sensor and ignition coil packs) are connected via electrical circuits. If these connections are not working properly, this could result in incorrect information being fed to the engine management system, causing a misfire.
The type “A” misfire is the most serious condition and indicates impending catalyst damage. If detected, the Malfunction Indicator Lamp (MIL) may flash once per second to alert the driver that immediate service is required.
There are many reasons for faulty fuel injectors but the three most common issues are clogging in your car`s fuel injectors, leaky and dirty injectors. You should remove the fuel injectors and clean them up before putting them back in for your car to function optimally.
Not only can a rich air/fuel ratio cause a backfire, a mixture that doesn`t have enough gasoline can cause a backfire, too. A “lean” mixture is one that doesn`t have enough fuel, and too much air.

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.

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.

Engine does not start after fueling
ANSWER : Hi There,
It sounds like your car’s evaporative emissions system may have some problems. The EVAP system prevents fuel vapors from the fuel tank from escaping into the atmosphere as you are fueling your car and while the fuel just sits in the tank. The EVAP system collects and temporarily stores the fuel vapors in the charcoal canister. The charcoal canister is filled with activated carbon pellets that can absorb the fuel vapors. When the engine is running, the fuel vapors are purged from the canister and burned in the engine. The vent control valve (solenoid) controls the flow of outside air in and out of the charcoal canister. When this is not working properly, you may experience the gas pump shutting off prematurely causing it to take a very long time to fill up your fuel tank. This is due to the excess fuel vapor that is present when the purge solenoid is not working properly by releasing these vapors. The gas pumps at the fuel station have automatic sensors on them (for safety reasons) that shut off automatically when too much fuel vapor is present. I would recommend having an expert from Your Mechanic come to your home to take a look at your car to diagnose your EVAP purge solenoid.

What would cause 1st cylinder misfire, multiple misfire, all fuel injectors circuits open and o2 sensors heater circuit high on a 2008 Dodge Charger
ANSWER : Hello. It sounds like you may have the wrong parts installed on the car. Due to the fact that multiple people have worked on it you may have some parts that do not meet specifications. From what it sounds like to me though you either do not have an ECM in the vehicle with the correct programming or you have a connection issue. If all of the grounds are not clean and tight then that will cause this. if they are then the computer needs to be programmed to your vehicle at the dealer and that may take care of it.

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.

Replaced fuel pump. Car won’t start. 2002 Infinity I35
ANSWER : Hi there – the metal component you describe is a fuel check valve on the fuel return line. Its function is to maintain a small amount of pressure in the fuel system so that starting does not require the fuel pump to run very long before the engine will start. Having replaced the fuel pump and fuel filter, I would check fuel pressure while the car is running. This is to check the fuel pump relay for burned contacts that won’t support full electrical current to the pump, and for proper fuel pressure – a malfunctioning fuel pressure regulator could also restrict power and higher speeds if pressure is too low. I would recommend an inspection of the fuel system 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.

Fuel supply related to engine misfire?
ANSWER : Engine misfires can be caused by a list of problems, but there are a few suspects that occur more than others. Generally, misfires are caused by either a spark or fuel issue or in cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition modules not working properly. When the misfire results from a fuel related issue, this is commonly related to a lean fuel condition (lack of sufficient fuel supply to the motor). Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass air flow sensor, a faulty or dirty idle air control valve or a vacuum or intake leak. When the fuel supplied to the combustion chamber is insufficient, this results in an ignition (spark) that is igniting a less than balanced load of fuel and air. This results in a misfire or an explosion in the cylinder that is much less powerful than the other cylinders. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. I would recommend having an expert from YourMechanic come to your location to diagnose your misfiring problem.

Car won’t start after sitting for 14 months
ANSWER : Hi there. Check the fuel pump to see if it is energizing, and check the fuel pump relay to see if it is clicking when you turn on the key. If the relay is not clicking, then remove the relay and check to see if there is any power with using a test light. If there is power, then swap the relay out with the horn relay and see if the relay clicks.

If the relay clicks, then the relay went out and needs to be replaced. If the relay still does not click, then check the ground circuit for continuity, which is the feed circuit to the fuel pump. If there is no continuity, then the fuel pump needs to be replaced.

If you need further assistance troubleshooting your vehicle, then seek out a certified technician, such as one from YourMechanic, who can come to your location to determine why the car is not starting and suggest the necessary repairs.