2003 INFINITI Q45

Introduction

The 2003 INFINITI Q45 was a full-size luxury sedan praised for its powerful engine, sophisticated interior, and advanced safety features. It came standard with a 4.5-liter V8 engine producing 340 horsepower and 335 lb-ft of torque. The only transmission option was a 5-speed automatic.

Engine

• 4.5L V8

  • Leaking oil pan gasket: Premature failure of the oil pan gasket can cause oil leaks. Symptoms include oil spots under the vehicle and a drop in oil level. Replacement of the gasket is required. Estimated Cost to Fix: $200 - $400
  • Faulty knock sensors: Malfunctioning knock sensors may lead to engine performance issues, including detonation and reduced power. Replacement of the sensors is necessary. Estimated Cost to Fix: $400 - $600
  • Intake manifold gasket failure: A faulty intake manifold gasket can cause vacuum leaks, resulting in rough idling, reduced engine power, and increased emissions. Replacement of the gasket is needed. Estimated Cost to Fix: $500 - $800
  • Timing chain tensioner failure: Premature failure of the timing chain tensioner can lead to rattling noises, rough idling, and reduced engine power. Replacement of the tensioner and timing chain is required. Estimated Cost to Fix: $1,000 - $1,500+
  • Crankshaft position sensor failure: A faulty crankshaft position sensor can cause starting problems, engine stalling, and rough idling. Replacement of the sensor is the solution. Estimated Cost to Fix: $200 - $400+

Transmission

• 5-Speed Automatic

  • Transmission control module (TCM) failure: Malfunctions in the TCM can lead to erratic shifting, delayed responses, and transmission slipping. Replacement of the TCM is required. Estimated Cost to Fix: $1,000 - $1,500+

Suspension

• Front lower control arms: Premature wear in the front lower control arms can cause excessive tire wear, vibration, and a knocking noise when turning or braking. Replacement of the control arms is the solution. Estimated Cost to Fix: $400 - $600 per side
• Rear air suspension failure: The rear air suspension system may experience leaks or compressor malfunctions, resulting in uneven ride height or a lack of ride height adjustment. Repair or replacement of the air suspension components is necessary. Estimated Cost to Fix: $1,000 - $2,000+

Electrical

• Alternator failure: Premature failure of the alternator can cause electrical problems, including battery drain, dim headlights, and vehicle stalling. Replacement of the alternator is required. Estimated Cost to Fix: $500 - $700+
• Starter motor failure: A faulty starter motor can prevent the engine from starting. Replacement of the starter is the solution. Estimated Cost to Fix: $300 - $500+
• Battery drain: Electrical system malfunctions, such as faulty relays or a parasitic draw, can lead to battery drain. Diagnosis and repair of the underlying issue are required. Estimated Cost to Fix: $200 - $500+

Exterior

• Door lock actuators failure: Failure of the door lock actuators can prevent the doors from locking or unlocking. Replacement of the actuators is necessary. Estimated Cost to Fix: $200 - $400 per door
• Rear spoiler separation: The rear spoiler may become detached from the trunk lid due to adhesive failure. Reattachment or replacement of the spoiler is required. Estimated Cost to Fix: $200 - $500+

Interior

• Heater core failure: A faulty heater core can cause a lack of heat in the cabin. Replacement of the heater core is needed. Estimated Cost to Fix: $500 - $700+
• Climate control unit failure: Malfunctions in the climate control unit can lead to issues with temperature control, airflow, or fan speed. Replacement of the unit is often required. Estimated Cost to Fix: $500 - $700+
• Bose stereo system failure: The Bose stereo system may experience speaker failures, volume control issues, or sound distortion. Replacement of the faulty components is necessary. Estimated Cost to Fix: $300 - $600+

Recalls

• NHTSA Campaign ID 06E035000: Airbag warning light may not activate.
• NHTSA Campaign ID 06E057000: Fuel system may leak.

Summary

Overall, while the 2003 INFINITI Q45 is a luxurious and powerful sedan, it has experienced several common issues, particularly with the engine and transmission. Engine issues can be severe and expensive to fix, with potential costs exceeding $1,500. Transmission problems can also be costly, with repairs ranging from $1,000 to $2,000 or more. Other issues, such as suspension, electrical, and interior problems, are typically less severe and less expensive to fix.