Experiencing a clicking sound when you turn the key on your 7.3 Powerstroke but the engine refuses to crank can be frustrating. Many jump to conclusions about glow plugs, especially in colder climates. However, while glow plugs are essential for cold starts in diesel engines, they are often not the culprit behind a no-crank situation, especially in a 7.3 Powerstroke. In fact, as the original article correctly points out, these engines should start fine even without glow plugs unless it’s extremely cold. Using starting fluid like “Either” is strongly discouraged as it can cause engine damage. Instead, the clicking sound you hear is more likely related to electrical components in your starting system. Let’s explore how to diagnose this issue, and whether a scan tool is needed right away.
The clicking sound you’re hearing often indicates a problem in the starter circuit, preventing the starter motor from engaging and turning the engine over. A common source of this click is the starter relay. Depending on the year of your 7.3 Powerstroke, particularly if it’s an ’01 model year, you might have a fender-mounted starter relay in the engine bay. Listen closely when you turn the key to the start position – is the click coming from this relay?
Testing the Starter Relay
A simple test to bypass the relay is to jump the two large terminals on the relay solenoid together using a jumper wire or a screwdriver with an insulated handle. Safety First: Ensure the vehicle is in park or neutral and the parking brake is firmly engaged. If, upon jumping these terminals, the engine cranks and starts, then you’ve likely identified a faulty starter relay. Replacing the relay should resolve the issue.
Checking the Starter Motor
If jumping the relay doesn’t make the engine crank, the next component to investigate is the starter motor itself. Sometimes, the starter motor solenoid can become stuck or the motor itself can develop dead spots. A classic, albeit sometimes temporary, fix is the “hammer test.” Locate the starter motor (usually mounted to the engine block near the transmission) and give it a few firm but not overly aggressive taps with a hammer or wrench. Avoid hitting any wiring or delicate parts. After tapping, try starting the engine again. If it cranks, the starter motor is likely the problem and will need replacement soon. This is often a sign of worn starter motor components.
Battery and Electrical System Assessment
If neither the relay jump nor the starter tap worked, the issue might stem from insufficient power reaching the starter. A weak battery or poor electrical connections can prevent the starter from engaging. A basic test to assess your battery system is the headlight test. Turn your headlights on and observe their brightness. Then, have someone turn the ignition key to the start position while you watch the headlights. If the headlights dim dramatically, turning very yellow or almost going out, it indicates a significant voltage drop. This suggests weak batteries that cannot provide enough current to crank the engine. You should test your batteries’ voltage and consider load testing them to determine their condition. Also, check all battery terminals and cable connections for corrosion and ensure they are clean and tight.
When to Consider a Scan Tool for “Clicks”
Now, where does a scan tool fit into diagnosing these “clicks”? While a generic OBD-II scan tool might not directly pinpoint a faulty starter relay or a worn starter motor causing the “clicks,” it can still be a valuable tool in the diagnostic process, especially for a 7.3 Powerstroke.
Here’s how a scan tool can help:
- Battery Voltage Monitoring: Many scan tools can display live data, including battery voltage. You can monitor the voltage while attempting to crank the engine. A significant voltage drop visible on the scan tool can confirm a battery issue even if the headlight test is inconclusive.
- Error Code Check: Although a “no crank” due to a relay or starter might not always throw specific codes directly related to those components, a scan tool can reveal other underlying electrical system issues. There might be codes related to low voltage, PCM (Powertrain Control Module) communication problems, or other sensor issues that, while not directly causing the “clicks,” could be contributing to starting problems or masking other issues.
- Advanced Diagnostics (with higher-end scan tools): More advanced scan tools designed for diesel diagnostics, especially those with Ford-specific capabilities, might offer deeper insights. They could potentially monitor starter circuit parameters, relay status (though less common for basic relays), and provide more detailed electrical system diagnostics. These tools are particularly useful for pinpointing less obvious electrical faults.
Conclusion
In the case of a 7.3 Powerstroke clicking but not cranking, start with the fundamental checks: the starter relay, the starter motor itself, and the battery system. These are often the most common culprits. While a scan tool isn’t the first tool you’ll reach for to diagnose the “clicks” themselves, it becomes increasingly valuable for confirming battery health, ruling out other electrical system faults, and potentially uncovering deeper diagnostic information, especially when using more advanced scan tools. For basic “click” diagnosis, a multimeter and some hands-on troubleshooting are often sufficient. However, for a comprehensive understanding of your 7.3 Powerstroke’s starting system and overall health, incorporating a scan tool into your diagnostic routine is a wise step. If you’ve gone through these steps and are still facing issues, it’s always recommended to consult a qualified mechanic for further diagnosis and repair.
