2001 INFINITI QX4

The 2001 INFINITI QX4 is a luxury SUV based on the Nissan Pathfinder, known for its comfortable ride, capable four-wheel-drive system, and upscale interior. It came standard with a 3.5L V6 engine producing around 240 horsepower and 265 lb-ft of torque, paired with a 4-speed automatic transmission. People generally liked the QX4 for its reliability, off-road capabilities, and luxurious feel compared to other SUVs of the time. Common dislikes included its fuel economy and some minor electrical gremlins.

Engine

3.5L VQ35DE V6

• Timing Belt Failure
  • Description/Symptoms: The timing belt can fail prematurely, leading to catastrophic engine damage. Symptoms include rough running, misfires, and a ticking noise from the engine.
  • Solution: Replace the timing belt according to the manufacturer’s recommended interval (around 60,000 miles).
  • Estimated Cost to Fix: $400 - $800+
  • Recalls: None Found
• Oil Leaks
  • Description/Symptoms: Oil leaks are common, particularly from the valve cover gaskets and the rear main seal. Symptoms include oil spots under the car and a burning oil smell.
  • Solution: Replace the leaking gaskets or seals.
  • Estimated Cost to Fix: $150 - $400+
  • Recalls: None Found
• Idle Air Control Valve Failure
  • Description/Symptoms: The Idle Air Control Valve can fail, causing the vehicle to idle roughly or stall.
  • Solution: Replace the Idle Air Control Valve.
  • Estimated Cost to Fix: $200 - $400+
  • Recalls: None Found

Transmission

4-Speed Automatic (RE4R01A)

• Transmission Slipping
  • Description/Symptoms: Transmission slipping, especially between gears, can occur as the vehicle ages. This can be caused by worn clutch packs or valve body issues.
  • Solution: Fluid flush may temporarily help. However, a rebuild or replacement is often necessary.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Harsh Shifting
  • Description/Symptoms: Harsh or erratic shifting can be caused by low transmission fluid, a faulty valve body, or worn solenoids.
  • Solution: Check and adjust fluid levels, replace the valve body, or replace the solenoids.
  • Estimated Cost to Fix: $200 - $1,000+
  • Recalls: None Found

Suspension

• Front Strut Failure
  • Description/Symptoms: Front struts wear out, leading to a bouncy ride, poor handling, and increased braking distance.
  • Solution: Replace the front struts.
  • Estimated Cost to Fix: $300 - $600+
  • Recalls: None Found
• Rear Shock Absorber Failure
  • Description/Symptoms: Similar to the front struts, the rear shocks can fail, causing a loss of control.
  • Solution: Replace the rear shocks.
  • Estimated Cost to Fix: $200 - $400+
  • Recalls: None Found

Electrical

• Power Window Motor Failure
  • Description/Symptoms: Power windows stop working due to motor failure or regulator issues.
  • Solution: Replace the window motor or regulator.
  • Estimated Cost to Fix: $150 - $300+
  • Recalls: None Found
• Sunroof Problems
  • Description/Symptoms: Sunroof malfunctions, including sticking, failing to open/close completely, or leaking.
  • Solution: Repair or replace the sunroof motor, track, or seals.
  • Estimated Cost to Fix: $200 - $500+
  • Recalls: None Found
• ABS Sensor Failure
  • Description/Symptoms: ABS light turns on, indicating a faulty ABS sensor. This can affect braking performance.
  • Solution: Replace the faulty ABS sensor.
  • Estimated Cost to Fix: $100 - $300+
  • Recalls: None Found

Exterior

• Rust on Rocker Panels and Lower Doors
  • Description/Symptoms: Rust develops on the rocker panels, fenders, and lower doors, especially in areas with harsh winters and road salt.
  • Solution: Rust repair or panel replacement.
  • Estimated Cost to Fix: $300 - $1,000+ (per panel)
  • Recalls: None Found
• Headlight Lens Clouding
  • Description/Symptoms: Headlight lenses become cloudy and yellowed, reducing visibility at night.
  • Solution: Headlight lens restoration kit or headlight replacement.
  • Estimated Cost to Fix: $30 - $200+
  • Recalls: None Found

Interior

• Climate Control Issues
  • Description/Symptoms: The climate control system can malfunction, blowing only hot or cold air, or failing to adjust temperature properly.
  • Solution: Replace the blend door actuator or control module.
  • Estimated Cost to Fix: $200 - $500+
  • Recalls: None Found
• Radio/Stereo Problems
  • Description/Symptoms: Radio or stereo malfunctions, including failing to power on, static, or speaker issues.
  • Solution: Replace or repair the head unit or speakers.
  • Estimated Cost to Fix: $100 - $400+
  • Recalls: None Found

Summary

The 2001 INFINITI QX4 is a generally reliable SUV, but it is subject to age-related issues. The most significant concerns revolve around potential timing belt failure, oil leaks, transmission problems, and electrical issues. While some fixes are relatively inexpensive, others, such as transmission repairs or rust remediation, can be costly. Potential buyers should carefully inspect the vehicle, paying close attention to the engine, transmission, and undercarriage for signs of wear, leaks, or rust. A pre-purchase inspection by a qualified mechanic is highly recommended.