15 Reasons Your RC Car Don’t Run and How to Fix It (Solved)

When your RC car stops running, it can be frustrating, especially if you’re in the mood for a race. But, quite often, the cause may be something simple. The most common reason may be that your battery is dead. Other reasons an RC car won’t run may be a poor connection between the car and the remote, dirty or damaged motor, poor motor connection, burned-out speed controls or resistors, and many others. 

Before taking your RC car to the garage for complete repairs or deciding to tear it apart yourself, check for clear signs of damage and go over easy-to-fix trouble area of your RC. 

RC Car Losing Power Fix

When your remote-controlled car won’t run, it most likely is because of a power issue. Hence, you need to figure out the problem before tearing your car apart. Once you know what to fix, it’s easier to get on the process yourself or with a hired technical help.
Once your RC car loses power, here are some quick fixes to keep them working: 

• Check the on and off switch: Sometimes, a problem as little as your power button, may be the problem. Get a flashlight and check if the on button is properly positioned. 
• Replace Batteries: RC cars require a functional battery performance to work well. If your battery lacks power and you’re considering replacing them, check the transmitter model, get quality replacement batteries, clean the battery compartment, then make sure to install them properly. 
• Check the fuel: most RC cars like the Nitro model run on fuel. So, make sure to check that there’s enough fuel to power up the car. If there is, check if the fuel is expired.
  If it is, it’s time to pour in new fuel. 
• Get a reliable transmitter and frequency that matches the brand: Each transmitter differs for RC brands. Using the wrong one would make the RC car stop running. Plus, the frequency needs to match the transmitter.
• Reconnect motor wiring: loose or disconnected wires can make some part of the RC work, while others wouldn’t. Check that you don’t have a loose wire before tearing your RC car apart.

Nitro Engine Loses Power

A Nitro RC car relies on fuel to run properly. So, if your nitro car won’t power, it may be due to fuel issues. Check that the fuel is full. If there’s little to no fuel in the fuel tank, your RC car won’t move.
It’s also important to check that the fuel is fresh. Fuel does expire, and when they do, it might pose a danger to your RC cars. 

Nitro Engine Won’t Pull Fuel

Priming your Nitro RC car can be difficult, but it doesn’t have to be a challenge. If you’re finding it hard to pull fuel in your carburetor, the problem could be from a lean, too small, or clogged carburetor. So, to pull fuel in your Nitro engine;

• Blow through the pressure line. If your fuel flows through this process, it’s a pressure issue. To do this, check that the exhaust seals and header have no ripe or tears. Then try blowing the pressure pipe and holding the throttle. 
• Make sure the fuel tank seal is not missing or worn out. Worn or missing fuel tank seals on the fuel lid may hinder your chances of getting fuel on your Nitro RC cars.
• Make sure the carburetor seal on the engine block intake is tight. It allows your fuel to pull in. 

Examine and Solve – Nitro RC Car Keeps Cutting Out

Sometimes, you start the engine of your Nitro car, but it sits and is idle. Or, you apply the brakes without opening the throttle only for the engine to stall.
When your nitro RC car keeps cutting off, it could be that: 

• The slide keeps getting pushed by the throttle servo. Make sure the slide is in place. 
• The carburetor is incorrectly adjusted: Reset it to ½ turn leaner.
• The idle speed (RPM)  is set too low. So, increase the speed. 
• The glow plug is weak or worn out: Test and replace the glow plug.
• Insufficient fuel tank pressure: Check that there are no leaks in the fuel lines and tank.
•  Dirt blockage: this can block the passage of fuel. So, check that the carburetor fuel inlet and fuel filter are not blocked: If blocked, remove and clean with a nitro solution. 
• Worn out engine: find replacement parts or repair engine.
• Stretched or broken clutch spring: find a replacement. 

Nitro Loses Power at Full Throttle

When your engine loses power at full throttle, you may have a lean bog on your High-speed Needle (HSN) or a rich Low-Speed Needle (LSN). To resolve this, tune the HSN by ¼ and take this same amount of the LSN.
When you do this, the HSN sounds crispier and won’t cut off. Rather, it leaves some amount of smoke.

Electric RC Car Loses Power

Have you checked the antenna? Does your RC car have the right frequency? If yes, then other things you want to observe.
If your electric RC loses power check these 3 things:

• Noisy sounds: if you pick up any grinding or whirring sound from your RC when you start the throttle, you most likely have a slipped pinion gear. Try to reconnect the gears or get a new replacement for them. 
• No sounds: if you hear no sounds but can feel your steering running, it’s probably a loose wire. Look for loose wires that run to and from your motor. If you find any, it’s best to re-solder loose wires. 
• No movement or noise: if you can’t hear any noise, or can’t feel any movement from the steering, you most likely have a worn-out motor. Get a good replacement for it. 

RC Car Brushless Motor Loses Power

Usually, brushless motors won’t lose power due to their high working power. 

If your brushless motor loses power, it may be due to bad insulation, current load, high RPM, which causes overheating, and high current load. Make sure to inspect, clean, and get a replacement for any part when necessary. 

RC Car Brushed Motor Loses Power

While brushed motors have a lifespan of 1000 to 3000 hours, they tend to lose power if you don’t maintain them. 

The brushes in the commuter perform most of the job. So, you may need to change them. Plus, they must stay cool at all times. Overheating can burn the commuter, brushes, or weaken the magnets, potentially making the brushed motor lose power.
So, make sure to keep the temperature below 150°F. 

Electric RC Car Cutting Out

What do you do if you notice your electrically powered RC car keeps cutting off?
It could be from a worn-out motor, poorly connected ESC, servo failure, or faulty radio system. 

Switch the ESC on and run a benchmark test to see its performance. It’s also ideal to carry out this test on your motor. If you find out you’ve got a faulty ESC or motor, the good news is that you can reliable replacements for them. 

For your radio system, make sure the wiring between the receiver battery and ESC is properly set up. This way, you keep your electric RC car from cutting out. 

Electric RC Car Cuts out at Full Throttle

When driving your electric-powered RC car, you might notice that the throttle appears to hesitate before power kicks in fully and finally shuts off in minutes. A problem like this could spring from the motor or ESC. 

• Check the switch on the ESC: sometimes, a disconnected on and off switch on your ESC might be the fault. If you notice this problem, replace the ESC. 
• Check the motor: if the switch on the ESC isn’t the problem, then it’s likely a faulty motor. Try replacing the motor to see if it works better. If it doesn’t, check for loose battery connections. 

RC Car Not Responding to Controller

When your servo stops working, it means the RC car won’t respond to the transmitter. Try unplugging the servos from the controller, then replugging them into a working servo. 

If it still doesn’t work, you want to replace the servo. 

RC Car Beeping

RC car beeping signifies a loose stick, which isn’t in its usual midpoint, forward position. The solution for this is to calibrate the RC. To do this, make sure the battery is at full capacity. 

RC Car Going Backward Instead of Forwards

A problem like this differs for electric and nitro-powered RC cars. 

• Nitro RC cars: the servo-reverse switch might be set in the wrong direction.
  Reset to channel 2 to help it move in the right direction. It may also be due to the differentials being incorrectly installed. Make sure the differentials are not installed upside down. 
• Electric RC’s: apart from the servo-reverse, your electronic speed, motor phase wires, and motor power leads may be set incorrectly. Check that they are all properly connected using the owner’s manual.

RC Car Going Slower Than It Should 

If your RC model seems sluggish, it may be that the battery is not fully charged. If you have a full battery, the motor may have reached its limit. Get replacement when necessary. 

RC Car Not Responding to Throttle

An unresponsive throttle may be caused by: 

• damaged servo wires, 
• motor failure, 
• battery failure, 
• incorrect setup, 
• throttle server failure,
•  transmitter failure or incompatible transmitter and receiver, 
• unaligned gears, 
• uncalibrated ESC.
  Find your owner’s manual to know the best possible solutions for these faults. 

Conclusion

There are various reasons why your RC car won’t run, from disconnected servo wires to faulty motors, transmitters, throttle server, battery, wrong set up, burned-out speed controls, and many others. The good news, troubleshooting steps like this will help you get your RC car back on track.
But, if you won’t enjoy troubleshooting or won’t have time to do so, it’s best to let the skilled technicians do the job.