Sometimes the truck will start and run just fine, and other times it will barely want to start and I need to press the gas pedal

When I go to start my truck sometimes it starts and runs just fine or it will not start at all or actually get wants to start but cannot get it to start or if I can get it started I push the gas too hard it'll die out I'm wondering if it's my fuel pump or not and what it could possibly be something else
Experienced mechanics share their insights in answering this question :
Hello. This can be caused by a few different things. If the vehicle will run by pressing lightly on the gas pedal then it may be a bad idle control valve. If it sticks, it will allow too much air into the engine and cause it to run like this.

It can also be a weak fuel pump or an air flow meter issue. If the engine runs fine once it is started, then I would check the computer for codes first. If none are present, then I would run the engine and see what the sensor readings are to see if anything comes up faulty.

If those are also fine, then I check the fuel pressure to see if the pump is getting weak or to see if the pressure bleeds off while the vehicle sits. If you are thinking of having this starting issue inspected, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this problem.

How to Identify and Fix Common car Problems ?

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There are many causes of hard starting but illustrative ones are a faulty engine coolant temperature switch (sensor), malfunctioning idle air control (IAC) valve, vacuum and EGR leaks, inadequate fuel delivery or pressure (clogged fuel filter, injectors), and contaminated or old gasoline.
Fuel injector nozzles can become clogged over time, which can lead to a sputtering engine, slow acceleration and the car not having enough power. Fuel injectors can be cleaned if the problem is caught early, but as the conditions worsens, the injectors may have to be replaced.
With today`s sophisticated fully electronic diesel engines there can be a whole variety of reasons why your Ford Ranger refuses to start. Usually, the 3 most common causes are a dead battery, an alternator problem, or a bad starter. Other electrical gremlins will cause intermittent starting or stalling without warning.
Let`s Diagnose: Why Car Won`t Start Unless I Give It Gas? Unlike other hard starting problems related to car battery, this trouble indicates that either the mixture of air and fuel is not igniting or the engine is receiving an insufficient amount of air and fuel for combustion.
If the car cranks when you turn the key, but the engine won`t start, it could be because fuel isn`t getting to the engine. One potential reason for this could be dirty fuel injectors. Over time, the fuel injector nozzles can become clogged with rust, corrosion or debris.
The “stiff” gas pedal issue is most likely caused by a dirty throttle body in the air intake system. Cleaning the throttle body should relieve this symptom. The lack of “Drive” selection, unless first selecting “Reverse”, could be a loose or misadjusted shift cable or shift linkage issue.
A clogged fuel or air filter can make your engine sputter and your acceleration lag because the engine is not getting enough fuel or air, respectively. The combustion chamber needs the correct amount of air and fuel in order to generate combustion efficiently.
Ford F 150 jerk on acceleration can be caused by an oil pan gasket, which may need to be replaced. Ford F 150 jerk on acceleration can also be caused by a faulty throttle positioning sensor. If the vehicle jerks when accelerating, this will cause an increase in fuel consumption and may need to be replaced.
If your vehicle won`t start, it`s usually caused by a dying or dead battery, loose or corroded connection cables, a bad alternator or an issue with the starter. It can be hard to determine if you`re dealing with a battery or an alternator problem.
A dead battery is the most common reason why engines fail to start up. A common reason for batteries to fail is drain. Your car`s battery typically expends a small portion of its storage to start your car up, and then recharges from your alternator as you move.
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.
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.
Odds are, if you smell gas while cranking the engine, it`s getting fuel. It`s probably not getting spark. Common causes for no spark: Bad crankshaft sensor. Bad camshaft sensor.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Sometimes the truck will start and run just fine, and other times it will barely want to start and I need to press the gas pedal
ANSWER : Hello. This can be caused by a few different things. If the vehicle will run by pressing lightly on the gas pedal then it may be a bad idle control valve. If it sticks, it will allow too much air into the engine and cause it to run like this.

It can also be a weak fuel pump or an air flow meter issue. If the engine runs fine once it is started, then I would check the computer for codes first. If none are present, then I would run the engine and see what the sensor readings are to see if anything comes up faulty.

If those are also fine, then I check the fuel pressure to see if the pump is getting weak or to see if the pressure bleeds off while the vehicle sits. If you are thinking of having this starting issue inspected, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this problem.

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.

My Ford Focus CZX3 2006 doesn’t want to run when I press the gas pedal
ANSWER : Hi there:

This type of situation can occur due to multiple mechanical or electrical problems either within the transmission or it can be a braking system failure. If the vehicle will not move at all, even in neutral, then the brakes may be locked up due to brake fluid contamination or a brake master cylinder failure. If only the front wheels will not move then it may be a transmission problem or a linkage issue. Before you wait too long, I’d recommend get some help from a certified mechanic that can diagnose your car not moving issue, so that they can determine precisely what’s causing this problem with your Ford Focus.

Cranks over start than dies
ANSWER : Hi There,
The idle air control valve is a small valve on the engine’s intake system that reads the air intake as it comes into the motor. This is controlled by the car’s ECM which uses this information to make adjustments to the air/fuel ratio depending on various inputs such as outside air temperature, intake air temperature, load and various other things. As you accelerate, your car’s engine is receiving a much higher dose of fuel than when at idle and conversely, when you let off the gas pedal, there is a sudden change in this fuel supply as a result of your foot letting off the pedal. When this happens, the job of the idle air control valve is to bring this deceleration down to a slow and smooth idle rather than suddenly cutting off the fuel supply causing the motor to die. When the idle air control valve is not working properly, this cause a disruption in this process resulting in the engine not being able to idle properly. I would recommend having a professional come to your location to diagnose and inspect your vehicle.

Vehicle start sometimes sometimes runs, and other time don’t start. Run and shutdown! 2002 Toyota Sequoia
ANSWER : Hello – the first task is to extract problem codes, whether the Check Engine light is on or not. Most auto parts stores will do this for you for free on a "time-available" basis. These will greatly simplify diagnosis. If no codes are evident, checking for spark at the plug will help narrow the problem to ignition or fuel problems. A failing crankshaft position sensor can cause any/all of the problems you are experiencing, but won’t necessarily set a problem code. I recommend a no start inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

Stalling when gas pedal pressed down quickly or too fast also happening when stopping at lights and sometimes during idle.
ANSWER : Hey there. It sounds like you may have a mass air sensor problem or an intake leak between the throttle body and mass air sensor. This is a perfect example of why you should have a mechanic conduct a pre-purchase inspection. The inspection would have identified the vehicle has problems before you decided to purchase it. My best recommendation now would be to have a local expert, like one from YourMechanic, come to your car’s location to diagnose the stalling issue and have this corrected properly.

My Blazer will crank over but not start by itself. It needs starting fluid to start.
ANSWER : Hi there. If you have not replaced your EGR valve, mass air flow sensor or the TPS on your Blazer, you might want to start with these repairs. It is also possible that the throttle body itself is damaged, especially if you’re able to start it on fluid. If you want to avoid chasing parts and repairs, the best solution may be to have a professional mobile mechanic come to your location and complete a car is hard to start inspection.

Odometer has lines, won’t start unless I put fuel in the intake. The fuel pump keeps running and doesn’t shut off? Seems like the truck wants to start.
ANSWER : Hi there. From the description you have provided, you’ve replaced the fuel pressure regulator, the fuel pump never shuts off and puts fuel in the throttle body, it runs until the fuel is gone, and the odometer has lines instead of mileage. This would appear to be a fuel control problem and communication failure.

Some possibilities are that the PCM (Powertrain Control Module) has shorted internally causing the fuel pump relay to be commanded continuously on, injector driver circuits are inoperative, or failed communication to the IPC (Instrument Panel Cluster).

This all needs to be confirmed through diagnostic procedures. I recommend having your vehicle’s fuel pump never shuts off, truck won’t start condition be diagnosed and repaired by a certified technician, such as one from YourMechanic.