Cranks and runs rough have to keep foot in gas to keep running. Has new fuel pump and died while driving after pump was changed
Changed the fuel pump last week after it went out and saw the vent valve on the fuel tank had all of the nipples broke off. Got a new tank to change it but haven't changed it out yet. Noticed the water pump was leaking water the other day and drove it home to fix the tank and pump issue and the truck shut off a half a mile from my house. Finally got it cranked up and limped it to the house. Changed water pump, thermostat and oil this morning cranked the truck and it is running real rough and have to keep my foot on the gas to keep it running. Also has a slight knock in motor. I am at a sta
Experienced mechanics share their insights in answering this question :
Check fuel pressure. There are only three possible explanations: a fault in fuel supply (plugged filter, injectors, etc.); ignition system problems; and air induction including the idle air control valve, throttle position sensor, mass air flow sensor and vacuum leaks including the PCV and EGR systems. If obvious, and easy to check, possibilities do not reveal the fault, the recommended service to request is a rough running diagnostic and the responding certified mechanic will travel right to your location and get this diagnosed and resolved for you. It is also possible that diagnostic trouble codes have set and the mechanic will attempt to retrieve those using an appropriate scan tool. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.
How to Identify and Fix Common car Problems ?
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A damaged fuel pump might make a loud, whining sound that you`ll hear from your gas tank. The pump may also make this noise if you`re low on fuel or the fuel in your tank is contaminated. The normal noise your pump makes is a low hum. Loud whining indicates there is a problem.
There are only three possible explanations: a fault in fuel supply (plugged filter, injectors, etc.); ignition system problems; and air induction including the idle air control valve, throttle position sensor, mass air flow sensor and vacuum leaks including the PCV and EGR systems.
What to Look For: A bad fuel pump can cause difficulty when starting the vehicle, a rough idle, and stalling. Clogged Fuel Filter – The fuel filter filters the contaminants from gasoline. Over time it can become clogged, which slows the flow of fuel.
Most of the time when this occurs it is due to a lack of voltage. It can be from a failing battery or alternator. Most of the time the issue is the battery.
A bad fuel pump may overheat and inadequately deliver gas to the engine, causing it to run hot and turn off while on the road. In this scenario, your vehicle may start back up after overheating and shutting down, only to do the same thing a half-hour later. This scenario is a common sign of a bad fuel pump.
This symptom often points to an issue with either your exhaust system, fuel or dirty or worn out parts. In internal combustion running vehicles, and incomplete combustion will cause a sputter. And while a sputtering engine might not seem like a serious issue, it often results in an expensive repair when ignored.
Sterling, Virginia — Have you noticed that your car slows down when you let off the gas pedal even before you hit the brakes? Part of the reason you slow down when you lift your foot is because your engine is no longer receiving the fuel it needs to maintain its speed.
Oxygen (O2) sensor
An oxygen sensor monitors and analyzes the amount of oxygen in a vehicle`s exhaust system after combustion. A dirty, damaged or malfunctioning O2 sensor (or sensors) affects the air/fuel mixture, causing the engine to idle rough.
Why does my car not accelerate when I push the gas? A car not accelerating properly can be caused by a number of things. It could be due to the throttle body, gas tank, spark plugs, or the ECU. It could also be because you have a dirty air filter or a clogged fuel filter.
One of the most common causes of a sputtering engine is an issue with the vehicle`s fuel system—the filter, pump, and injectors. These three critical components work together to ensure fuel flows smoothly from the fuel tank to your engine`s fuel injectors, and then pumps into the engine evenly.
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.
Fuel pumps have been known to last for over 200,000 miles in some cases. 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.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Cranks and runs rough have to keep foot in gas to keep running. Has new fuel pump and died while driving after pump was changed
ANSWER : Check fuel pressure. There are only three possible explanations: a fault in fuel supply (plugged filter, injectors, etc.); ignition system problems; and air induction including the idle air control valve, throttle position sensor, mass air flow sensor and vacuum leaks including the PCV and EGR systems. If obvious, and easy to check, possibilities do not reveal the fault, the recommended service to request is a rough running diagnostic and the responding certified mechanic will travel right to your location and get this diagnosed and resolved for you. It is also possible that diagnostic trouble codes have set and the mechanic will attempt to retrieve those using an appropriate scan tool. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.
I changed fuel pump and truck ran great for 3 days. Now after 3 days truck dies. It will start runs few min then dies like before
ANSWER : Check the bottom of the fuel tank for sediment. Age and mileage could have accumulated a lot of it at the bottom of the tank. If you did not, check and change the fuel filter. Rule of thumb – replace the fuel filter any time you replace a fuel pump. Also, check the wiring for any chaffing on the fuel pump when you remove it. While your problem is kind of unique, I have seen many GM truck fuel tank baffle loosen over time, occasionally rubbing against the fuel pump can intermittently short it out and/or block the fuel pump pick up. To have this diagnosed, consider having a certified expert from YourMechanic inspect the stalling issue to have this corrected.
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.
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.
I changed the fuel pump and truck ran great for 3 days. Now after 3 days, the truck dies. It will start running for a few minutes, then dies like before.
ANSWER : Hi there, thanks for writing in. I’d be happy to help. It sounds like you should disconnect the connector to the fuel pump and inspect it for any signs of getting hot. The female connections may be too loose on the fuel pump and lose contact after running and getting hot. If there are indeed any signs of problems, then I’d suggest replacing connector and adding dielectric lube to pins before installation. This should solve the problem, but if you continue to experience issues, feel free to reach out to us for help again.
Runs fine for days then acts like running out of gas and then dies and try restart and runs then dies ,when I turn key on you hea
ANSWER : The fuel pump in the fuel tank is designed to have low pressure and high volume to feed the front fuel pump the right amount fuel. The front fuel pump supplies the engine with high pressure to the engine.
When you do not hear the pump run then the fuel pump is bad and should be replaced along with the relay. You should not have to replace the in tank pump if it is running. I’d suggest replacing the fuel filter as well.
I’d suggest getting this inspected by a qualified technician, such as one from YourMechanic, to diagnose your stalling issue and make the necessary repairs.
When I crank my car it won’t keep running unless I keep my foot on the gas. As soon as I release the gas pedal my car stops running
ANSWER : The first thing you need to check for in a case like yours is air leaks. Check all the rubber parts and hoses under the hood for good condition and connection. The amount of fuel delivered to your engine is determined by the air that flows in and any air that gets in through a leak without being measured means less fuel being injected. There are of course a number of other possible causes; a failed Mass Air Flow Sensor for example, but they will require special skills and equipment to be examined. You can have this conveniently checked out by contacting Your Mechanic. They can send a technician to your home or office to check out your car and let you know exactly what it will take to solve your problem.
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.
Engine crank, no coil spark, fuel pump does not kick in.
ANSWER : Hi there. There could be multiple issues causing your lack of spark problem, ranging from a minor electrical short in the main relay to an issue with your ECU. In order to know for sure, you should have a professional mobile mechanic complete an electrical problems inspection.
