Why Your 2010 Mitsubishi Eclipse is Clicking and Stalling

How to Fix Clicking Noise

A persistent clicking or popping noise from your 2010 Mitsubishi Eclipse can be alarming, often pointing to a failing component that needs immediate attention. While the sound can be confusing, owner reports and technical discussions consistently point to a few critical areas, with the engine harness being a primary suspect for electrical-related clicking that can lead to stalling or no-start conditions. As one owner shared their diagnostic journey: "My spark plugs look good, spark plugs wires look good and both aren’t old less than 1 year. So my next step is to test my injectors to see if they’re the issue." This logical process of elimination is key to solving the problem.

Symptoms

Owners of the 2010 Mitsubishi Eclipse describe a range of symptoms that accompany or are related to clicking noises. The most direct report is a loud popping or clicking sound, particularly noticeable at low speeds. This auditory clue is often the first and most obvious sign that something is amiss. One owner detailed this experience, stating, "My 2001 Mitsubishi Eclipse GT 3.0L V6 is making loud popping noises at low speeds (under 30mph)." While this quote references an earlier model, the symptom and underlying causes for a 2010 model are often analogous, especially concerning drivetrain components.

Beyond the noise itself, this issue frequently manifests in more severe operational problems. A recurring theme in owner discussions is the vehicle stalling or failing to start altogether. These symptoms suggest the clicking noise may not just be a benign sound but an indicator of an electrical fault interrupting critical systems. The noise could be a relay rapidly cycling or an injector failing to fire properly due to a wiring issue. Another related symptom mentioned is a grinding sound, which could indicate a separate but possibly concurrent mechanical issue, such as a problem with the flywheel or timing components, that an owner might initially describe as a severe "clicking" or "popping."

The context of the noise is crucial for diagnosis. Is it present all the time, or only when turning, accelerating, or when the engine is cold? Does it correlate with the blink of a warning light? Owners also express frustration with the cascading effects, such as being unable to locate correct replacement parts once the root cause is found, highlighting a common secondary challenge. As one owner lamented regarding a different but related repair, "It says that it fits my car but idk if it’s my error or the part didn’t actually fit."

Most Likely Cause

Based on synthesized data from owner reports and technical forums, the most likely cause of a clicking noise in a 2010 Mitsubishi Eclipse, especially one associated with stalling or a no-start condition, is a fault in the engine wiring harness. The harness is the central nervous system of your engine, delivering power and signals to essential components like fuel injectors, sensors, and ignition coils. Over time, heat, vibration, and exposure can cause the wiring insulation to brittle and crack, leading to short circuits, poor connections, or broken wires.

A compromised wire in the harness can cause a fuel injector to click erratically or not fire at all, which an owner might hear as a rapid ticking. More critically, a short or open circuit can cause relays in the power distribution center to click repeatedly as they try and fail to establish a stable connection. This can directly lead to intermittent stalling or a complete failure to start, as critical engine computers lose power or sensor data. The mention of checking injectors by an owner directly supports this line of reasoning, as injector operation is wholly dependent on a clean signal from the engine control unit (ECU) through the harness.

While other components like a failing CV axle (for popping during turns) or a faulty flywheel (for a grinding click at the bellhousing) are possible, the linkage to electrical issues like stalling strongly points toward the harness as the primary culprit. Corrosion and poor connections at harness plugs can create the same symptoms. As evidenced in discussions about other Eclipse models, electrical gremlins are a common thread, with owners digging into fuse boxes and wiring diagrams: "Here’s where the fuse is shown in the circuit diagram, between fusible link 8 and the ABS Power Relay."

How to Diagnose

Diagnosing a clicking noise requires a methodical approach to isolate the sound's origin. You will need a basic mechanic's stethoscope (or a long screwdriver), a digital multimeter (DMM), and a good flashlight.

Step 1: Locate the Sound. With the engine cold for safety, start the vehicle and listen carefully. Use the stethoscope or place the handle of a long screwdriver against your ear and gently touch the tip to different areas. Probe near each fuel injector, the relay box under the hood, the starter motor, and the transmission bellhousing. Try to pinpoint whether the click is high-pitched (like an injector or relay) or low and heavy (like a mechanical knock).

Step 2: Check for Correlation with Problems. Does the clicking speed up with engine RPM? If so, it's likely tied to a rotating component or a cycled event like fuel injection. Does it click randomly and then the engine stalls? This points strongly to an electrical fault. Try to reproduce the stall condition while monitoring the click.

Step 3: Visual Harness Inspection. This is critical. With the engine off and the battery disconnected, visually inspect the entire engine wiring harness. Look for cracked, melted, or brittle insulation, especially where the harness passes near sharp edges, hot exhaust components, or where it is subject to tension. Check all the major connectors, such as those at the injectors, coil packs, crankshaft position sensor, and ECU. Look for green or white corrosion on the pins.

Step 4: Electrical Testing. Using your multimeter, you can perform key tests. Check for battery voltage at the main engine relays when the key is on. Test the resistance of suspect wires for continuity. A common test is to check the injector circuit. With the connector disconnected, you can check for resistance across the injector itself (typically 10-16 ohms) and for power and ground at the harness connector with the key on. As one owner logically progressed, "My next step is to test my injectors to see if they’re the issue." This testing inherently checks the harness's ability to deliver signal and power.

Step-by-Step Fix

Replacing or repairing a damaged engine harness is a detailed but manageable DIY job for a patient enthusiast. Here is a step-by-step guide based on best practices and owner experiences.

1. Disconnect the Battery: Always start by disconnecting the negative battery terminal to prevent shorts or electrical damage.
2. Document and Photograph: Before removing a single connector, take extensive photos and notes of the harness routing. Note where it passes through brackets, clips, and alongside other components. Label connectors with masking tape if they are not obviously unique.
3. Remove the Intake Assembly: To access the entire harness, you will likely need to remove the air intake tube, air filter box, and possibly the throttle body or intake manifold plenum. This provides necessary workspace.
4. Unplug All Connectors: Methodically unplug every connector attached to the harness. This includes sensors (coolant temp, MAP, crankshaft, camshaft), actuators (idle air control, throttle position), injectors, coil packs, and any ground straps.
5. Release the Harness: Carefully release the harness from all its clips, brackets, and tie-wraps. Be gentle to avoid damaging any intact wires. Note how it is routed through the firewall to the ECU inside the cabin.
6. Install the New Harness: Compare the new harness to the old one to ensure completeness. Route it exactly as the old one was, using your photos as a guide. Re-attach all clips and brackets.
7. Reconnect All Components: Plug every sensor and actuator back in. Double-check that each connection is secure and fully seated. Reattach all ground straps.
8. Reinstall Intake Components: Put the intake assembly, throttle body, and any other removed parts back in place.
9. Reconnect the Battery: Reconnect the negative battery terminal.
10. Test for Function: Start the engine and listen carefully. The erratic clicking should be gone. Use your OBD-II scanner to check for any pending codes. Test drive the vehicle to ensure the stalling issue is resolved.

As one owner shared regarding the importance of correct parts, a lesson that applies here: "I know Autozone and O’Rillys will often give wrong parts." Ensuring you have the exact, correct harness for your 2010 Eclipse model (GS, GT, Spyder) and engine (4-cylinder or V6) is paramount to success.

Parts and Tools Needed

• Primary Part: Engine Wiring Harness. You must get the correct part for your specific trim and engine. A dealer parts department can provide the exact part number using your VIN. Aftermarket options exist but verify fitment meticulously.
• Tools:
  • Basic socket set and ratchet (metric)
  • Screwdrivers (flathead and Phillips)
  • Needle-nose pliers
  • Digital Multimeter (DMM)
  • Mechanic's stethoscope
  • Flashlight
  • Trim removal tools (for interior ECU access if needed)
  • Masking tape and pen for labeling
• Consumables:
  • Electrical contact cleaner
  • Dielectric grease
  • Zip ties (to secure the new harness)

Real Owner Costs

The cost to fix a clicking noise caused by a harness issue varies dramatically between DIY and professional repair.

DIY Repair: The largest expense is the harness itself. A new OEM harness from a dealer can cost between $300 and $800 depending on complexity. A quality aftermarket or salvaged harness may range from $150 to $400. If you only need to repair a section, a wiring repair kit and heat-shrink tubing might cost under $50. The DIY labor cost is your time, typically 4-8 hours for a first-timer.

Professional Repair: A shop will charge for both parts and labor. Expect 3-5 hours of labor at rates from $100 to $150 per hour. With the cost of a new harness, the total bill can easily range from $800 to $1,500 or more. One owner's experience with rust issues highlights how problems can compound: "It has rust on the end where the hose would connect and other spots internal spots, In general its got bad rust issues. My issue now is locating a replacement." While about a different part, this reflects the reality of repair costs on a vehicle of this age, where one issue can reveal others.

Prevention

Preventing major harness failure revolves around protecting the wiring from its main enemies: heat, abrasion, and corrosion.

1. Regular Visual Inspections: Periodically, when checking oil or coolant, take a moment to look at sections of the engine harness, especially near the exhaust manifold and where it rubs against the body.
2. Secure Loose Wires: If you see a harness sagging or rubbing, secure it with a new clip or a high-temperature resistant zip tie. Never let wiring rest on sharp metal edges.
3. Protect During Work: When performing other repairs, be mindful of the harness. Don't rest heavy parts on it, and avoid pulling on wires to move them.
4. Address Leaks Promptly: Oil, coolant, or power steering fluid can degrade wire insulation over time. Fix any fluid leaks as soon as they are discovered.
5. Use Dielectric Grease: When reconnecting electrical plugs, a small dab of dielectric grease on the connector seals can prevent moisture ingress and corrosion.

What Owners Say

Real experiences from MITSUBISHI owners:

Owner Experiences

"My 2001 Mitsubishi Eclipse GT 3.0L V6 is making loud popping noises at low speeds (under 30mph). I'm thinking it's the passenger-side CV axle and/or wheel bearing." — PerformanceMission63 (source)

"01 Mitsubishi Eclipse GT 3.0L makes popping noise at low speeds My 2001 Mitsubishi Eclipse GT 3.0L V6 is making loud popping noises at low speeds (under 30mph)." — PerformanceMission63 (source)

"My spark plugs look good, spark plugs wires look good and both aren’t old less than 1 year. So my next step is to test my injectors to see if they’re the issue." — Raider_831 (source)

FAQ

Q: How long does it take to replace an engine harness? A: For a proficient DIYer with all the right tools, plan for a full day (6-8 hours). If it's your first major wiring job, it could take a weekend. A professional mechanic would likely quote 3-5 hours.

Q: Can I drive my Eclipse with a clicking noise and stalling? A: It is not safe. Intermittent stalling can happen at any time, including in traffic or while making a turn, leading to a loss of power steering and brakes. Have the vehicle towed to your repair location.

Q: Is a clicking noise a common issue on the 2010 Eclipse? A: While not a universal epidemic, electrical issues and harness degradation are common in many vehicles of this age, including the Eclipse. Heat cycles and vibration take their toll on wiring over 10+ years.

Q: DIY vs mechanic – what's recommended for this fix? A: This is an intermediate to advanced DIY job. If you are methodical, good with labeling, and comfortable with basic engine disassembly, you can save significant money. If the thought of dozens of electrical connectors is overwhelming, or your diagnosis is uncertain, a trusted mechanic is the wise choice. As owners note, getting the right part is half the battle, so a professional's resources can be valuable.

Q: Could it be the fuel injectors making the click? A: Yes, injectors normally click rapidly during operation. However, a loud, irregular click or tick from one injector could indicate it is faulty or, more likely, not receiving the correct signal due to a wiring problem in the harness. Testing the injector and its circuit, as one owner planned, is the correct diagnostic step.

Q: What if the harness looks okay but I still have the problem? A: The issue could be internal corrosion within a connector or a break in a wire that is not visually obvious. This is where systematic testing with a multimeter for continuity and voltage drop is essential. The problem could also lie in a specific component, like a failing relay or the starter solenoid, which were also mentioned in owner data.