How to Start a Car With a Bad Fuel Pump
If your car’s fuel pump goes bad, you may be able to get it started again through the application of external manual pressure—click here to find out more.
Written by Andrew Biro
Reviewed by Melanie Reiff
If your car’s fuel pump has gone bad—but hasn’t completely stopped working—you should still be able to start it by applying manual pressure, attaching a fuel pressure gauge, or making sure the engine receives consistent heat.
As the component of your vehicle which actively transports fuel from the tank to the engine, the fuel pump is an incredibly important part, one that your car can’t run without. Over time, however, the pump can degrade or become contaminated, and no longer work correctly. This can make it difficult—but not impossible—to start your car.
Learning how to start—let alone recognize—a car with a bad fuel pump is something every car owner should know to avoid potentially damaging their vehicle. That’s why
Jerry
, the expert driving app and car insurance
comparison tool, has put together the following guide on how to start a car with a bad fuel pump.Compare insurance quotes from 50+ carriers with Jerry in under 45 seconds (Title in payload)
4.7/5 rating on the App Store | Trusted by 5+ million customers and 7 million cars4.7/5 app rating | Trusted by 5M+ driversWhat is a fuel pump?
Before we can tell you how to start a car with a bad fuel pump, we need to define what a fuel pump is and the purpose it serves. This will give you a better understanding of why the start-up methods work.
Fundamentally, the fuel pump in your vehicle exists to pump fuel from the tank to the engine and can either be mechanically or electrically powered. Mechanical fuel pumps use a low-pressure system to move fuel from the tank through the carburetor and are located on the outside of the gas tank.
Electrical fuel pumps, on the other hand, send a strong, positive electrical current through the fuel lines, forcing the fuel out of the tank and into the engine. Both pump types help maintain the crucial air-to-fuel ratio that makes the combustion process possible.
If your fuel pump starts to go bad, it can result in either too much or too little fuel being pumped into the engine. This ultimately throws off the air-to-fuel ratio in your engine cylinders, resulting in worsening performance.
In the event your fuel pump fails altogether, you will not be able to start your vehicle at all.
How to start a car with a bad fuel pump
If you have the symptoms of a bad fuel pump (which we’ll outline later), you need to know how to get your car started so you can get it to a mechanic. Generally speaking, there is one reputable way of doing this—applying manual external pressure. There are two other possible ways, but they may give mixed results.
- Manual external pressure: In essence, this method seeks to manually replicate the pressure needed to start your car through the application of an external pressure source. The easiest way to do this is by hooking up an air pump to your gas tank and running it until the tank becomes pressurized
- Maintain consistent engine temperature: Very high temperatures are a sign that your fuel pump may be going bad, so one thing you can try is to let the engine cool down a bit. This will allow the fuel pump to reset without the need for pressure
- Attach a fuel pressure gauge: If you have one, or decide to buy one, attach a fuel pressure gauge to your car’s engine. This will allow you to both diagnose whether or not the pump is actually at fault and can also help to get your engine started again
As previously stated, the only method here with consistent success is the application of manual external pressure. You can try the other two if you like, but they may not always work.
How do I know if my fuel pump is bad?
Now that you know what the fuel pump is and what it does, you can learn how to recognize when it starts to go bad—check the list below for some of the most common symptoms of a bad fuel pump:
- A loud whining noise: One of the first signs of a bad fuel tank is hearing a loud whining noise—rather than the usual low hum—coming from the fuel tank
- Hard start: If getting your engine to turn over starts taking more than one try, your fuel pump may be suffering from advanced wear and tear, causing it to weaken
- Loss of power: If your car starts to lose power when accelerating or driving up a hill, making these tasks more difficult, the fuel pump is likely at fault
- Worsening gas mileage: If you start noticing your gas mileage decreasing, your fuel pump may have a faulty valve that is allowing more fuel than necessary to escape the tank
- Stalling in warm temperatures: If your vehicle starts to stall even when temperatures are high, you’re probably dealing with a bad fuel pump
How to find affordable car insurance
Depending on the type of vehicle you drive, replacing a bad fuel pump can be a big expense—but your insurance doesn’t have to be, as long as you use
Jerry
.As the nation’s #1 licensed
car insurance
comparison app, Jerry makes shopping for affordable rates easier than ever, saving the average user upwards of $800 a year!Simply download the app, fill out a short questionnaire, and in as little as 45 seconds, Jerry will have compared dozens of competitive quotes from 50+ trusted insurance companies to find you the best deals possible.
Once you find a policy that fits your needs, Jerry can even help you get signed up—without forcing you through hours of paperwork or tedious phone calls!
“You must get this app! It’s my first time getting my own insurance, so I called a few companies myself. Their rates priced me around $600/month. I usedJerryand my rates went down to $250/month. I’m so happy!” —Melissa C.
Jerry sends free alerts to keep your car up-to-date so you can avoid costly repairs
* checking your rate won’t affect your credit score
Get ahead of my car maintenance
* checking your rate won’t affect your credit score
Will a car start with a bad fuel pump?
In most cases, yes. As long as your fuel pump hasn’t completely stopped working, your car will still start even if the pump isn’t operating at full capacity—you’ll just have a much harder time getting the engine going.
What does a car with a bad fuel pump sound like?
If your vehicle’s fuel pump has gone bad, you should be able to hear a loud, whining noise coming from the vicinity of the gas tank—a marked difference from the usual low hum it makes.
Estimate your repair costs for free with GarageGuard™
Simplify your car maintenance with Jerry.
4.7
