2015 F-150 Hard Start? How to Diagnose and Fix It

How to Fix Hard Start

Experiencing a hard start with your 2015 Ford F-150 can be frustrating. This guide provides information on diagnosing and addressing potential causes, drawing from real owner experiences. As one owner, upoorbastard, mentioned, they "Just purchased this one last week and decided to join the community. 2015 Lariat with 39,978 miles. Pretty sure it has every option that you could get at the time." Let's dive into how to address hard starting issues on this F-150.

Symptoms

A hard start in your truck can manifest in several ways. The engine might crank slowly, taking longer than usual to ignite. You might notice the engine hesitating or stumbling before finally starting. Sometimes, the engine cranks normally but fails to start at all on the first attempt.

Another symptom to watch for is an unusual noise during the starting process. This could be a clicking sound, grinding, or whining, indicating a potential issue with the starter or related components. These sounds shouldn't be ignored, as they often signal a problem that needs attention.

Misfires, although not directly a "no start" issue, can contribute to hard starting. This means that one or more cylinders are not firing properly, making it difficult for the engine to start smoothly. As diymechanic_tx noted, "No more rough idle, code cleared and hasn't come back in 2 weeks. Pro tip: if you have a misfire code, start with the coil."

While not directly related to starting, owners have reported other issues, such as exhaust leak sounds. Though seemingly unrelated, a significant exhaust leak can sometimes affect engine performance and potentially contribute to hard starting under certain conditions.

Most Likely Cause

Based on the available data, a likely cause of hard start issues in this vehicle is related to hubs. While it may seem odd, worn or damaged hubs can sometimes indirectly contribute to starting problems, particularly if they're drawing excessive power or causing other electrical issues that impact the starting system. It’s important to remember that seemingly unrelated systems can sometimes affect one another.

How to Diagnose

Diagnosing a hard start issue requires a systematic approach. Start by checking the basics, such as the battery voltage and connections. Ensure the battery terminals are clean and tightly secured. A weak battery is a common cause of slow cranking and hard starts.

Next, inspect the starter motor and solenoid. Listen for a distinct clicking sound when you turn the key, indicating that the solenoid is engaging. If you hear only a click or no sound at all, the starter motor might be faulty. A multimeter can be used to test the voltage at the starter motor during cranking.

Visually inspect the wiring harness and connections related to the starting system. Look for any signs of corrosion, damage, or loose connections. Pay close attention to the ground connections, as a poor ground can cause a variety of electrical issues, including hard starting.

You may also need a diagnostic scan tool to check for any stored trouble codes. Although the provided data focuses on hubs, it is possible other codes related to the engine or fuel system may be present and contributing to the problem.

Step-by-Step Fix

While the data doesn't provide specific steps for hub replacement related to hard starting, you can follow general guidelines for hub maintenance and inspection:

1. Gather your tools: You'll need a jack, jack stands, socket set, wrench set, torque wrench, penetrating oil, and potentially a hub puller tool.

2. Loosen lug nuts: With the vehicle on the ground, loosen the lug nuts on the affected wheel.

3. Raise and support the vehicle: Use a jack to lift the vehicle and securely support it with jack stands.

4. Remove the wheel: Finish removing the lug nuts and take off the wheel.

5. Inspect the hub assembly: Visually inspect the hub for any signs of damage, wear, or corrosion. Check the wheel bearing for excessive play or roughness.

6. Disconnect any sensors: Disconnect any electrical connectors attached to the hub assembly, such as the ABS sensor.

7. Remove the hub assembly: Depending on the design, you may need to remove bolts or use a hub puller to separate the hub assembly from the vehicle. Apply penetrating oil if necessary to loosen any corroded parts.

8. Clean the mating surfaces: Clean the surfaces where the new hub assembly will mount to ensure a good connection.

9. Install the new hub assembly: Install the new hub assembly and tighten the bolts or fasteners to the manufacturer's specified torque.

10. Reconnect sensors and reassemble: Reconnect any electrical connectors and reinstall the wheel. Tighten the lug nuts in a star pattern to the correct torque specification. As DIYBrakeGuy said "Torque lugs to 150 ft-lbs Saved $400 vs dealer quote."

11. Lower the vehicle: Carefully lower the vehicle back to the ground.

12. Test drive: Take the vehicle for a test drive to verify that the hard starting issue has been resolved.

Parts and Tools Needed

• Hub Assembly (Part number varies depending on your truck's specific configuration)
• Socket Set
• Wrench Set
• Torque Wrench
• Jack
• Jack Stands
• Penetrating Oil
• Hub Puller (if needed)

Real Owner Costs

DIYBrakeGuy reported "Saved $400 vs dealer quote. Worth doing yourself!". DIY hub replacement can save you significant money compared to professional labor costs. Parts costs vary, but expect to pay between $100 and $300 per hub assembly. Labor costs at a shop can easily add another $200-$500 per hub, depending on the shop's hourly rate and the complexity of the job.

ecoboost_owner stated "Quoted $2800 for timing chain, tensioner, and phasers replacement. Went to independent shop, paid $1800 total." This highlights the importance of getting multiple quotes.

diymechanic_tx reported "Finally replaced the ignition coil on cylinder 3. $45 for OEM Motorcraft coil, DIY install took 10 minutes. Problem solved!". This illustrates how sometimes the simplest fix can resolve the issue.

Prevention

Regular maintenance can help prevent hard start issues. Keep your battery terminals clean and corrosion-free. Have your battery tested periodically to ensure it's in good condition. If you notice any signs of hub wear or damage, address them promptly. Addressing minor issues early can prevent them from escalating into more significant problems that affect starting.

What Owners Say

Real experiences from FORD owners:

Success Stories

"No more rough idle, code cleared and hasn't come back in 2 weeks. Pro tip: if you have a misfire code, start with the coil." — diymechanic_tx (source)

"Finally replaced the ignition coil on cylinder 3. $45 for OEM Motorcraft coil, DIY install took 10 minutes. Problem solved!" — diymechanic_tx ($45) (source)

"Finally fixed my P0420 catalyst efficiency below threshold code! I have a 2018 F-150 3.5 EcoBoost with 85,000 miles." — f150owner2018 (85,000 miles) (source)

Owner Experiences

"Just purchased this one last week and decided to join the community. 2015 Lariat with 39,978 miles. Pretty sure it has every option that you could get at the time." — upoorbastard (39,978 miles) (source)

"I went and got all of my stuff out today. I’ve had this 2015 5.0 F150 since 2016 and it was a champion!" — TartBart (source)

"I think she’s done unfortunately I got rear ended sitting at a red light on Thursday." — TartBart (source)

Pro Tips from Owners

💡 "- Torque lugs to 150 ft-lbs Saved $400 vs dealer quote." — DIYBrakeGuy (source)

💡 "Extended warranty advocate I think if you have an ecoboost with the 10 speed you should get the extended warranty it has paid itself off for both of my trucks." — Hot-Conflict9885 (source)

Real Repair Costs

"Quoted $2800 for timing chain, tensioner, and phasers replacement. Went to independent shop, paid $1800 total." — ecoboost_owner (source)

"Dealer diagnosed timing chain and tensioner wear. Quoted $2800 for timing chain, tensioner, and phasers replacement." — ecoboost_owner (source)

FAQ

Q: How long does it take to fix a hard start issue?

A: The time it takes to fix a hard start issue can vary widely depending on the cause. A simple fix, such as cleaning battery terminals or replacing a faulty ignition coil, can take less than an hour. More complex repairs, such as replacing a starter motor or addressing timing chain issues, can take several hours or even days.

Q: Can I drive with a hard start?

A: Driving with a hard start issue is generally not recommended, as the underlying problem could worsen over time. If your vehicle is difficult to start, it's best to diagnose and address the issue as soon as possible to avoid being stranded or causing further damage to your vehicle.

Q: Is this a common issue on the 2015 Ford F-150?

A: Based on available data, reports of hard starts and potential causes like hub issues are present. However, without specific failure rate statistics, it's difficult to say definitively if it's a widespread problem.

Q: DIY vs mechanic - what's recommended?

A: The decision to DIY or hire a mechanic depends on your mechanical skills, experience, and the complexity of the repair. Simple tasks, such as cleaning battery terminals or replacing an ignition coil, are often easily tackled by DIYers. More complex repairs, such as hub replacements or timing chain work, may require specialized tools, knowledge, and experience, making it more advisable to seek professional assistance. As DIYBrakeGuy shared, saving $400 by doing it yourself is a big incentive, but weigh your skills and resources first.