Changed fuel pump and car still won’t start

My sons car suddenly died while driving on freeway. My brother said its the fuel pump, so we changed it. Now when you start the car it doesn't want to turnover but sometimes it sounds like its going to start and it doesn't. The battery is still good

My car has 11800 miles.

Experienced mechanics share their insights in answering this question :
Hello. There are many issue that could cause the vehicle to produce the symptoms you are experiencing.

If the fuel pump is new I would move on to checking the battery, and then ignition system.
I would also recommend scanning the computer for trouble codes to see if that may perhaps shed some light on what the source of the issue could be.

I’d recommend getting some assistance from a certified mechanic who can come to you and diagnose your no starting issue firsthand. Once a proper assessment is done, the necessary repairs can be made to get your son’s car going again.

How to Identify and Fix Common car Problems ?

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If your car doesn`t start with a new fuel pump, chances are the fuel pump is either not hooked up right or is broken. Double check that the pump is correctly installed and all hose attachments are plugged in. Next, check for any blockages along the fuel line—this can also cause your car not to start.
Your fuel pump doesn`t stop pushing gas through to the engine once you`ve started your vehicle; it also pumps gas to meet your vehicle`s speed. If the pump cannot produce a constant stream of gas at higher speeds, your vehicle`s engine will sputter and threaten to stall.
Irregular resistance within the fuel pump motor can lead to your car slowing down and being unable to accelerate. Failing to accelerate is a good sign that your vehicle`s fuel pump needs inspection.
As a result, Toyota recalled over 1.5 million vehicles, including the 2019 and 2020 RAV4s. Toyota says that a defective low-pressure fuel pump found in certain RAV4s may fail, causing the engine to stall while driving. Toyota will have dealers replace the fuel pump assembly.
Note: The fuel pump shut off switch reset button is usually located either under the dash in the driver compartment or under the driver or passenger seat. Just move the seat forward and pull back on the carpet or popping off the cover under the seat to access the switch.
If the relay fails slowly, then you might notice engine performance symptoms over time. For instance, as the fuel pump relay begins to falter, its ability to power the fuel pump dampens, which can lead to engine stalling when the engine cannot receive enough fuel for combustion.
Too much back pressure may cause the pump to stall if the fluid pressure overcomes the air pressure. To control flow, pressure and performance of an AODD pump it is important to have an air regulator installed to control the incoming air pressure.
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.
Just because you hear the fuel pump run does not mean it is pumping the correct pressure to the injection system. If the pressure is real low or the filter is plugged solid, then the pump may not get enough fuel to the fuel rail. The only way to know is to test the fuel pressure at the fuel rail test port.
The oxygen sensor can affect how much fuel your vehicle`s engine burns. By measuring oxygen levels in the exhaust, the O2 sensor helps to ensure your automobile meters and delivers the correct amount of fuel depending on the demands you place on the engine.
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.
If a fuel pump isn`t installed correctly, it either won`t work at all or won`t supply enough fuel to the engine. When the fuel pump isn`t working right, your engine isn`t getting the amount of fuel it needs to run well. Your engine loses power and fuel efficiency.
If a fuel pump isn`t installed correctly, it either won`t work at all or won`t supply enough fuel to the engine. When the fuel pump isn`t working right, your engine isn`t getting the amount of fuel it needs to run well. Your engine loses power and fuel efficiency.
Debris blocking the suction strainer or foot valve is the most common cause. A blockage in the intake line can cause the water in the pump casing to overheat and literally boil out of the casing causing the pump to lose prime.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

My car stutter starts, but only after driving it for a few minutes.
ANSWER : Hey there. This may also be caused by what is called the fuel pressure regulator. This is a unit that helps to maintain the fuel pressure at the proper level. When this is not working properly, the fuel pump may be pumping properly, but the fuel may not arrive at the fuel injectors at the proper psi. When this happens, this can cause a lean fuel condition which may cause the car to hesitate, misfire, or stall. If you would like to have an expert pinpoint the issue, a certified professional from YourMechanic can come to your car’s location to inspect the hard start problem and confirm which repairs are needed.

Car won’t start. The check engine light, battery light, and oil change light are coming on. I tried jumping the car and nothing happened. Why won’t my car start?
ANSWER : Hi and thanks for contacting Your Mechanic. If sometimes your vehicle will start with the new alternator and sometimes it won’t, then there is a loose connection in your charging system. Check all of the wires to the alternator and to the battery. Make sure that the battery cables are clean and tight. Make sure that the wires to the starter are clean and tight. A loose ground to the ignition system will cause the vehicle to not crank over. Check all of the ground wires from the battery to the starter. Make sure that they are clean and tight. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from Your Mechanic, that can assist you.

My car stutters after driving it for a few minutes – 2002 Toyota
ANSWER : This may also be caused by what is called the fuel pressure regulator. This is a unit that helps to maintain the fuel pressure at the proper level. When this is not working properly, the fuel pump may be pumping properly, but the fuel may not arrive at the fuel injectors at the proper psi. When this happens, this can cause a lean fuel condition which may cause the car to hesitate, misfire or stall. I would recommend having an expert from YourMechanic come to your location to diagnose your fuel pressure.

Changed battery and the fuel pump and car still slow to start. When it does start it shuts off without warning. Fuel filter is fine.
ANSWER : Hi there. The battery could be dead even though it has a full charge. There could be a dead cell or an over charged cell. Have the battery checked with a load tester. This will place a load on the battery and the battery is not to drop more than 3 volts during the test. If the battery drops more than 3 volts, then the battery needs replaced. Also, check the starter and ignition system for any faults. Look for corrosion on the ignition wires and see if the cables to the starter are loose. If you need further assistance with your no start situation, then seek out a professional, such as one from Your Mechanic, to help you.

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.

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.

New battery & fuel pump. Hours later car starts and shuts down 3X in a row. Finally it starts, 48 hours later, won’t start at all
ANSWER : Checking all the fuses was a good move. I would also want to put a scan tool on it and check for diagnostic trouble codes (DTCs) as well as seeing the data that the computer is seeing.

A fuel pressure test would be a good idea to verify correct pressure and so that you’d be able to eliminate that possibility. It should be 58psi on your Magnum.

I also recommend getting your battery tested (I know, it’s new, have it tested anyway) and be sure it’s charged to at least 75%. And yes, loose battery cable connections can result in electrical problems.

If you need some assistance with this, consider enlisting a certified mechanic who can perform the checks I’ve mentioned and diagnose your starting issue firsthand. The mechanic can then perform the necessary repairs once the problem has been isolated. Good luck.

My car is stutter starting and vibrating
ANSWER : Hi there:

Anytime a vehicle sits for extended periods of time, multiple components are compromised and may need to be replaced or properly serviced. However, what you just described in regards to the shop you took your Toyota is not uncommon. Most ’shops’ (especially chains) complete repairs by throwing parts at them to see if it works. What should be done, and what we offer at YourMechanic.com is to complete a inspection first to determine what’s causing these issues. If you’re having problems starting the Toyota, have one of our mobile mechanics complete a car is hard to start inspection first. This initial inspection will save you time and money in the short and long term; and ensure you have the right parts and service completed to fix your vehicle’s issues.