2002 Cadillac DeVille

The 2002 Cadillac DeVille is a full-size luxury sedan known for its comfortable ride, spacious interior, and distinctive styling. It was available with the 4.6L Northstar V8 engine. The Northstar V8 produced 275 horsepower and 300 lb-ft of torque in the base DeVille and DHS trims. The DeVille was only available with the 4T80E 4-speed automatic transmission. Owners generally liked the car’s smooth ride, quiet cabin, and powerful engine, but common complaints included issues with the electronics, excessive oil consumption, and costly repairs.

Engine

4.6L Northstar V8

• Excessive Oil Consumption
  • Description/Symptoms: The engine consumes an excessive amount of oil, sometimes requiring a quart or more every 1,000 miles. Blue smoke may be visible from the exhaust.
  • Solution: Some owners have tried using thicker oil or additives, but the underlying issue is often worn piston rings or valve stem seals. Rebuilding the engine or replacing it are the most reliable fixes.
  • Estimated Cost to Fix: $3,000 - $6,000+ for engine rebuild or replacement.
  • Recalls: None Found
• Head Gasket Failure
  • Description/Symptoms: Overheating, coolant loss, white smoke from the exhaust, and milky oil are all symptoms of a blown head gasket. This is a known weakness of the Northstar engine.
  • Solution: Replacing the head gaskets. This is a labor-intensive job.
  • Estimated Cost to Fix: $2,500 - $5,000+
  • Recalls: None Found
• Cooling System Issues
  • Description/Symptoms: Overheating due to a variety of causes, including a failing water pump, clogged radiator, or faulty thermostat.
  • Solution: Replace the water pump, flush the cooling system, replace the radiator, or replace the thermostat. Diagnose the specific cause of overheating before proceeding.
  • Estimated Cost to Fix: $200 - $800+ depending on the specific part.
  • Recalls: None Found

Transmission

4T80E 4-Speed Automatic

• Erratic Shifting/Slipping
  • Description/Symptoms: The transmission may shift erratically, slip between gears, or fail to shift at all.
  • Solution: In some cases, a fluid flush and filter change can resolve the issue. If the problem persists, the transmission may need to be rebuilt or replaced.
  • Estimated Cost to Fix: $200 - $400 for fluid flush and filter change; $2,000 - $4,000+ for rebuild or replacement.
  • Recalls: None Found
• Torque Converter Failure
  • Description/Symptoms: Shuddering or vibrations, especially at low speeds.
  • Solution: Replace the torque converter.
  • Estimated Cost to Fix: $800 - $1,500+
  • Recalls: None Found

Suspension

• Air Suspension Compressor Failure (If Equipped)
  • Description/Symptoms: The rear of the car sags, the “Service Ride Control” message appears on the dash, and the air compressor may run constantly or not at all.
  • Solution: Replace the air suspension compressor. Some owners choose to convert to a traditional coil spring suspension.
  • Estimated Cost to Fix: $300 - $800+ for compressor replacement; $500 - $1,000+ for coil spring conversion.
  • Recalls: None Found
• Strut/Shock Absorber Failure
  • Description/Symptoms: Bouncy or unstable ride, excessive body roll in corners, and leaking fluid from the struts/shocks.
  • Solution: Replace the struts and/or shocks.
  • Estimated Cost to Fix: $300 - $800+ per strut/shock depending on if it is the electronic suspension
  • Recalls: None Found

Electrical

• Failing Instrument Cluster
  • Description/Symptoms: The instrument cluster may intermittently fail or display incorrect information.
  • Solution: Repair or replace the instrument cluster.
  • Estimated Cost to Fix: $200 - $600+
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: The battery drains overnight or after a few days of non-use.
  • Solution: Diagnose and repair the source of the parasitic drain, which could be a faulty module, relay, or wiring issue.
  • Estimated Cost to Fix: $100 - $500+ depending on the complexity of the issue.
  • Recalls: None Found
• Headlight Issues
  • Description/Symptoms: Headlights flicker, or one or both headlights do not function.
  • Solution: Diagnose and replace the headlight, ballast, relay, or wiring harness.
  • Estimated Cost to Fix: $50 - $500+ depending on the headlight type (HID, halogen) and what needs replacement.
  • Recalls: None Found

Exterior

• Rust on Lower Body Panels
  • Description/Symptoms: Rust can develop on the lower body panels, especially around the rocker panels and wheel wells.
  • Solution: Repair or replace the rusted panels.
  • Estimated Cost to Fix: $300 - $1,000+ per panel depending on the severity of the rust.
  • Recalls: None Found

Interior

• Climate Control Issues
  • Description/Symptoms: The climate control system may blow hot air when it should be cold, or vice versa.
  • Solution: Diagnose and repair or replace the blend door actuator, climate control module, or other components.
  • Estimated Cost to Fix: $200 - $800+
  • Recalls: None Found
• Radio/Speaker Problems
  • Description/Symptoms: The radio may not work, or the speakers may be blown or produce distorted sound.
  • Solution: Replace the radio or speakers.
  • Estimated Cost to Fix: $100 - $500+
  • Recalls: None Found
• Sunroof Issues
  • Description/Symptoms: Sunroof may get stuck or not operate at all.
  • Solution: Repair or replace the sunroof motor, track, or switch.
  • Estimated Cost to Fix: $200 - $800+
  • Recalls: None Found

Summary

The 2002 Cadillac DeVille, while luxurious and comfortable, is prone to several common issues. Engine problems, particularly excessive oil consumption and head gasket failures in the Northstar V8, can be costly to repair. Suspension issues, especially with the air suspension system (if equipped), and electrical problems are also common. While many of these issues are related to the vehicle’s age, they should be considered when evaluating a potential purchase. The severity and cost of repairs can vary widely, but potential buyers should be prepared for potentially expensive maintenance and repair bills.