What is the 2002-2006 Nissan Altima Engine Control Module Relay / ECM Power Interruption Causing Stall or No-Start?

A well-documented problem on 2002-2006 Altima involves failure of the engine control module (ECM) relay, which can interrupt power to the ECM while driving or prevent the car from starting. Owners report sudden stalling, intermittent crank-no-start, or an engine that dies and res… Repairs typically run $0-$250. Severity: high.

What is the 2002-2006 Nissan Altima Rear Lower Control Arm Corrosion and Separation Risk?

In salt-belt states, 2002-2006 Altimas have a documented corrosion problem affecting the rear lower control arms. Severe rust can perforate the arm and eventually lead to cracking or separation, which alters rear wheel alignment and can affect vehicle control. Nissan issued a rec… Repairs typically run $0-$1,200. Severity: high.

What is the 2002-2006 Nissan Altima 2.5L Pre-Catalyst Breakdown Causing Excessive Oil Consumption and Engine Damage?

On many 2.5L QR25DE Altimas, the pre-catalytic converter material can deteriorate and be drawn back into the engine during valve overlap, scoring cylinder walls and accelerating oil consumption. Owners report needing to add oil frequently, loss of compression, rough running, and… Repairs typically run $900-$4,500. Severity: high.

What is the 2002-2006 Nissan Altima 2.5L QR25DE Head Gasket Failure Causing Coolant Loss and Overheating?

The first-generation-era 2.5L QR25DE (2002-2006) is well known for head gasket failure. Because the QR25 uses an open-deck block, the combustion ring of the gasket commonly fails into the combustion chamber, so owners often see disappearing coolant, overheating, and white exhaust… Repairs typically run $1,200-$2,500. Severity: high.

What is the 2002-2021 Nissan Altima Catalytic Converter Efficiency Failure (P0420) on the QR25DE?

P0420 (catalyst system efficiency below threshold) is one of the most common check-engine codes on the 2.5L Altima. The integrated exhaust-manifold/catalyst on these cars loses efficiency as the substrate degrades, the downstream oxygen sensor begins tracking the upstream sensor,… Repairs typically run $300-$1,850. Severity: medium.

What is the 2002-2012 Nissan Altima Power Steering Rack and High-Pressure Hose Leaks Leading to Loss of Assist?

Hydraulic power steering Altimas commonly develop leaks from the steering rack seals or high-pressure hose assemblies. Owners report groaning noises, fluid on the subframe, a burning smell from fluid contacting hot components, and progressively heavier steering effort. On higher-… Repairs typically run $250-$1,400. Severity: medium.

What is the 2002-2012 Nissan Altima Crankshaft and Camshaft Position Sensor Failures Causing Stalling or No-Start?

Altimas in this period frequently suffer from failing crankshaft position sensors and camshaft position sensors, especially on the 2.5L and 3.5L engines. Owners report intermittent stalling at stops or while driving, extended cranking, sudden no-start conditions, and check-engine… Repairs typically run $150-$600. Severity: medium.

What is the 2002-2016 Nissan Altima Exhaust Manifold Cracking Causing Ticking Noise and Exhaust Leak?

The exhaust manifold on the Altima is prone to developing cracks from repeated heat cycling, producing a ticking/tapping noise from the front of the engine that is loudest on cold start (and often quiets as the metal expands and the crack closes), along with an exhaust smell and… Repairs typically run $300-$1,500. Severity: medium.

What is the 2002-2012 Nissan Altima Front Wheel Bearing and Hub Failure Causing Humming Noise and ABS/Wheel Speed Issues?

A recurring higher-mileage Altima problem is front wheel bearing wear, often first noticed as a humming or growling noise that increases with road speed. As the bearing deteriorates, owners may feel vibration, looseness, or see ABS warnings if the integrated wheel speed signal be… Repairs typically run $250-$700. Severity: medium.

What is the 2002-2018 Nissan Altima QR25DE Ignition Coil Failures Causing Misfires (Cylinders 1 and 4)?

The 2.5L QR25DE four-cylinder is widely documented for repeated coil-on-plug ignition coil failures, with cylinders 1 and 4 (the end cylinders) failing most often. A failing coil triggers a single-cylinder misfire, rough idle, hesitation, and a flashing check engine light. Failur… Repairs typically run $60-$400. Severity: medium.

What is the 2002-2012 Nissan Altima Premature Front Strut Wear Causing Knocking / Clunk Over Bumps?

RepairPal documents front struts wearing prematurely on the Altima and producing a knocking/clunking noise from the front end, especially over bumps and uneven roads. The noise often comes from worn strut internals or a failing upper strut mount/bearing. Beyond noise and a bouncy… Repairs typically run $300-$800. Severity: medium.

Nissan · Known Issues

2003 Nissan Altima Problems: 13 Issues Every Owner Should Know

2003 model year · NHTSA recalls, manufacturer TSBs, and owner forum reports · Updated July 2026

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According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2003 Nissan Altima has 13 documented known issues, with 6 rated critical. The most serious are VQ35DE V6 Timing Chain Rattle from Worn Secondary Chain Guides and Tensioners ($1,200-$2,500 repair), Engine Control Module Relay / ECM Power Interruption Causing Stall or No-Start ($0-$250 repair), Rear Lower Control Arm Corrosion and Separation Risk ($0-$1,200 repair), 2.5L Pre-Catalyst Breakdown Causing Excessive Oil Consumption and Engine Damage ($900-$4,500 repair), Rusting Front Floorboards and Underbody Corrosion Near the Firewall/Subframe Area ($500-$3,000 repair) and 2.5L QR25DE Head Gasket Failure Causing Coolant Loss and Overheating ($1,200-$2,500 repair). Across all issues with published estimates, repair costs range from $60 to $4,500. DIY maintenance guides at au7o.io.

Frequently Asked Questions

What are the most common Nissan Altima problems?

According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2003 Nissan Altima has 13 documented issues. The most frequently reported are: VQ35DE V6 Timing Chain Rattle from Worn Secondary Chain Guides and Tensioners, Engine Control Module Relay / ECM Power Interruption Causing Stall or No-Start, Rear Lower Control Arm Corrosion and Separation Risk. Of these, 6 are rated critical and should be addressed promptly.

Is the Nissan Altima reliable?

The 2003 Nissan Altima has 13 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 6 issues are rated critical: VQ35DE V6 Timing Chain Rattle from Worn Secondary Chain Guides and Tensioners and Engine Control Module Relay / ECM Power Interruption Causing Stall or No-Start and Rear Lower Control Arm Corrosion and Separation Risk and 2.5L Pre-Catalyst Breakdown Causing Excessive Oil Consumption and Engine Damage and Rusting Front Floorboards and Underbody Corrosion Near the Firewall/Subframe Area and 2.5L QR25DE Head Gasket Failure Causing Coolant Loss and Overheating. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common Nissan Altima problems?

Repair costs for known Nissan Altima issues range from $0 to $4,500, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, VQ35DE V6 Timing Chain Rattle from Worn Secondary Chain Guides and Tensioners, typically costs $1,200-$2,500 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

What is the 2002-2018 Nissan Altima VQ35DE V6 Timing Chain Rattle from Worn Secondary Chain Guides and Tensioners?

On the 3.5L VQ35DE V6 the plastic secondary timing chain guides/tensioner shoes become brittle and break, and the secondary (cam) chain tensioners lose tension. This produces a loud rattle or whine from the front of the engine, most pronounced for the first few seconds of a cold… Repairs typically run $1,200-$2,500. Severity: high.

All 13 Known Issues

Other Nissan Models

Frequently Asked Questions

What are the most common Nissan Altima problems?

Is the Nissan Altima reliable?

How much does it cost to fix common Nissan Altima problems?

What is the 2002-2018 Nissan Altima VQ35DE V6 Timing Chain Rattle from Worn Secondary Chain Guides and Tensioners?

When Issues Typically Appear

2002-2018 Nissan Altima: VQ35DE V6 Timing Chain Rattle from Worn Secondary Chain Guides and Tensioners#

2002-2006 Nissan Altima: 2.5L Pre-Catalyst Breakdown Causing Excessive Oil Consumption and Engine Damage#

2002-2006 Nissan Altima: 2.5L QR25DE Head Gasket Failure Causing Coolant Loss and Overheating#

2002-2018 Nissan Altima: QR25DE Ignition Coil Failures Causing Misfires (Cylinders 1 and 4)#

2002-2006 Nissan Altima: Rear Lower Control Arm Corrosion and Separation Risk#

2002-2012 Nissan Altima: Power Steering Rack and High-Pressure Hose Leaks Leading to Loss of Assist#

2002-2012 Nissan Altima: Premature Front Strut Wear Causing Knocking / Clunk Over Bumps#

2002-2006 Nissan Altima: Engine Control Module Relay / ECM Power Interruption Causing Stall or No-Start#

2002-2012 Nissan Altima: Crankshaft and Camshaft Position Sensor Failures Causing Stalling or No-Start#

2000-2006 Nissan Altima: Rusting Front Floorboards and Underbody Corrosion Near the Firewall/Subframe Area#

2002-2021 Nissan Altima: Catalytic Converter Efficiency Failure (P0420) on the QR25DE#

2002-2016 Nissan Altima: Exhaust Manifold Cracking Causing Ticking Noise and Exhaust Leak#

2002-2012 Nissan Altima: Front Wheel Bearing and Hub Failure Causing Humming Noise and ABS/Wheel Speed Issues#