ATV Troubleshooting: ATV Has Spark and Fuel but Will Not Start

Your ATV won’t start. It is a frustrating situation that many ATV owners and riders will face. Since this is a troubleshooting guide, we will begin with the very basics. The first place to look is the fuel gauge to ensure sufficient gas, followed by testing for a spark.

To check for the spark, turn the ignition to the ON position, remove the spark plug, and ground the hex part of the plug to bare metal on the engine. Clean up any spilled gas, spin the engine, and watch for a spark jumping across the gap. To test gas flow, remove the carburetor’s fuel line, hold it over a container, and watch the flow. It should be the full stream of the line size.

If the ATV has spark, fuel, and gas flow but will not start, what comes next? If you find yourself in this challenging scenario, don’t panic. There are a few more things to try before you should call for help. Run through this checklist after determining that your ATV does have spark and fuel but will not start.

Check the Petcock Valve

Before running through an extensive list of complex problems and their solutions, start with the simple tests. If your ATV has spark and fuel but will not start, it could be something as simple as the petcock valve in the off position. Double-check the petcock valve as soon as you suspect engine issues.

If your ATV’s petcock valve is not in the ON or RUN position, put it there. Try starting the engine again. If that was the problem, of course, your ATV should start right up.

Check Your Gear

Is the ATV in park or in neutral? Checking your gear could be a simple solution to a simple problem, but people often overlook it. After checking for gas and ensuring a spark, always make sure that your ATV is in gear. Many ATVs are designed not to start unless it is in the right gear.

Put your ATV into the correct gear if need be, then try to restart it. With luck, this was the issue and you’re able to get going again with minimal troubleshooting.

Check the Battery

If you are not experiencing a simple run switch or gear issue, the battery could be the problem. This is the next step in your DIY troubleshooting checklist. Ideally, you have a battery tester in your traveling tool kit. Use it to check your battery’s status.

If it has a low charge or is dead, you can try boosting it. You may need to stop for the day to get the battery onto a charger. In the worst-case scenario, your battery won’t hold a charge and will need replacing.

If it does turn out to be a battery issue, consider investing in a battery charger for the future. If your ATV sits unused, you can plug it into a trickle charger to prevent unwanted drainage.

Consider Fuel Quality

Yes, you have gas, but how old is it? If you are trying to run your ATV using gas that has been sitting in the tank too long, that could be your problem. Degraded gas is not ideal for your ATV, and the machine may refuse to run. You may be able to change the fuel filter and replace the gas yourself. If you don’t want to or don’t feel comfortable, this is an easy job for a mechanic.

Check the Airflow

If you’ve gone through all of these steps and your ATV still won’t run, even though it has gas and spark, it could be an airflow issue. Exhaust needs to leave the system properly. And, the ATV requires air for combustion. If the engine isn’t getting enough air, the ATV will not start. The issue may lie within your air filters, which may need repairing or replacing.

Again, this is the kind of issue that might be within one’s DIY skills. However, if you are not comfortable handling these parts of an engine, leave it to the pros. You do not want to cause more damage with an at-home fix accidentally.

Other Engine Issues

Other engine and system issues could prevent an ATV from starting even with spark and fuel. An intake valve that is too tight is one example as this impacts compression. It could be a dirty carburetor or even a carb O-ring requiring replacement. If you are still stumped because the ATV won’t start when you have spark and fuel, it may be time to head to a mechanic for expert help.