“My car won’t start unless I give it gas. What should I do?” Our friend asked us this question. We faced this issue, too. And we realized that it was a common problem for many car owners.
Several factors contribute to the engine failure that requires gas to start. Troubleshooting the exact cause and solving it will be tricky. Yet, you can pull it off with the right tools and the correct solution.
We will show you all the possible causes of your car not starting unless you use gas. Let’s check it out and learn how to get back on the road!
5 Reasons Why My Car Won’t Start Unless I Give It Gas
Your car fails to start unless you give it gas due to the faulty compression system, MAF, air filter, throttle body, or fuel pump. You should test each component to determine the cause and take immediate action to fix it.
This “car won’t start unless I put gas in carb” issue makes you frustrated. In this case, keep calm and read our advice.
Compression Issues
Compression refers to the amount of pressure in the engine’s cylinders during the combustion process. If it’s too low or too high, the ability to build the pressure of your engine may have some problems.
For example, the low compression level often results from a weak spark. This issue is one of the reasons why your car won’t start unless you give it gas.
How to solve it?
First, you should confirm if the compression is the root of the problem by performing a compression test with these steps:
- Attach a compression tester to the spark plug.
- Disconnect the pump relay and ignition coil.
- Start your engine.
- If the difference in the compression ratio of two cylinders is around 40 PSI, your compressor may be faulty.
If you don’t have the tester, your fingers can substitute. Put them in the spark plug hole while starting your car. Then, you will feel the weak and strong air compression on your fingertips.
If the test reveals that the compression fails, take it to a qualified mechanic to diagnose and repair it.
Faulty MAF
The MAF (Mass Air Flow Sensor) sensor monitors the amount of air entering the intake. It rests between the air filter and throttle body to work with the airflow.
Why do I have to pump the gas pedal to start my car? The MAF sensor can be the cause.
When this device malfunctions, the engine has to handle an incorrect air-to-fuel ratio. Therefore, the ECM (Engine Control Module) fails to calculate the correct fuel delivery, making it hard to start your car unless you give it gas.
How to solve it?
The MAF may foul due to the pollutants that travel across the air filter. Hence, you must clean it first to see if that’s the problem. Since this component is sensitive, use only specialized cleaners for this task.
Here’s how to clean the MAF sensor correctly:
- Locate the MAF sensor.
- Disconnect the wires to remove the MAF sensor. Be careful not to touch its sensitive components at this step.
- Spray the cleaner on the sensor.
- Wait for it to dry.
- Reinstall it and test your engine by driving a short distance.
If cleaning can’t help, you should reset the MAF sensor. And if the error persists, replace the old MAF with a new one.
This replacement task is quite complicated. You need to follow the interactions in the guidebook carefully. Learning what to do after the replacement is also important .
Air Filter Issues
If you have to give car gas to start when cold, the air filter can be a part of the problem.
The air filter plays an important role in combustion engineering. It sits right in the engine compartment, preventing dirt and dust in the air from penetrating the combustion chamber.
Since it works with the dirt directly, you will notice dirt and moisture buildup in the filter vent. Without regular maintenance, the air filter will obstruct air entering your engine, leading to a hard start. The engine can only work if you give it gas.
The dirty air filter also causes other issues such as soot in the chamber, power loss, overheating, and a faulty ignition system.
How to fix it?
We do not often clean the air filter because this component is quite sensitive. If it’s the cause of your problem, we recommend replacing it instead. The instructions are as follows:
- Find the air filter housing, which is the circular or rectangular component near the engine.
- Loosen the bolts that secure the air filter cover and remove it.
- Remove the old air filter from its housing.
- Clean the housing of dirt and debris.
- Install the new air filter.
- Reinstall the cover.
- Test the new air filter.
The process sounds easy, right? However, it involves multiple steps, and some of them can be complex for beginners. So if you are not confident, contacting an experienced mechanic will be your best choice.
Clogged Throttle Body
Modern fuel-injected cars employ an intake system that uses the throttle to control the airflow in the motive. The throttle is important for igniting the fuel, too.
Unfortunately, dirt accumulation will block the throttle body, limiting air into the engine. Over time, the blockage will degrade your car’s performance. Then, unburnt fuel will travel across the exhaust system. As a result, your car won’t start unless you give gas.
How to solve it?
You can test the throttle body using a jack with alligator clips on the multimeter. If the reading changes suddenly, the throttle may have degraded.
If you have a faulty throttle body, consider replacing it by following the steps below:
- Disconnect the battery cables.
- Remove the throttle body using the steps outlined in the owner’s manual.
- Install the new throttle body.
- Reconnect the cables.
- Test drive your car to see if the new throttle body works.
Faulty Fuel Pump
The fuel pump transmits fuel from the gas tank to your engine. So if it can’t start unless you give it gas, check the fuel for any signs of damage.
A fuel pump often leads to poor fuel efficiency, reduced power, engine stalling, and illuminated engine light.
How to solve it?
You can check the fuel pump by measuring the vehicle’s fuel pump pressure. All you need to do is to insert a pressure gauge into the test port. If the reading is lower than recommended, the pumping system must have a problem.
It would be best to contact a certified mechanic to check your car’s fuel pump properly. If necessary, he will help you repair or replace it.
How To Maintain Your Car To Prevent Starting Issues?
Now you know how to fix your car when it can only start with gas. However, it’s still better to prevent starting issues than waiting for them to happen and learning how to fix them.
Regular maintenance is essential. And don’t worry! No matter which problem you try to prevent, the following tips will help:
Use High-Quality Components
Each component in your car has a different lifespan. As a general rule, the ones of higher quality can last longer.
For example, the air filter has to deal with a large amount of dirt every day. Hence, it should be durable to perform its task smoothly. If it has any issues and you replace it with a poor-quality one, you will easily notice a drop in efficiency. Then, you have to go for a new replacement soon.
Clean The Car Components Regularly
As you may notice, most of the causes arise from dirty components. For example, the air filter, fuel thump, and throttle will malfunction if not cleaned properly.
Hence, cleaning your car’s components is one of the most important maintenance tasks to bear in mind. Try to choose specialized cleaners to clean them without damage.
Conclusion
Hopefully, the issue of “my car won’t start unless I give it gas” won’t give you a hard time. If it occurs, perform some tests to find the exact cause. Then, go for the right solution to fix it.
The most common causes may come from the faulty air filter, compression, fuel pump, and some more. To prevent the problem from happening again, perform regular maintenance on your car.
We believe that with proper care, your car can start smoothly every time you turn the key. If you still have any questions about this topic, please comment below. We will reply soon.
Thank you for reading!

Hi! My name is Mark Stevens – the founder of Auto News Portal.
I wrote articles in the automotive industry for more than 10 years, published in USA, Europe and the Asia. I love sharing my knowledge and insights with fellow enthusiasts. Join me on this journey as we explore the exciting world of cars together!