What Is The Luxury Car For Nissan

Let's talk about the luxury arm of Nissan: Infiniti. For the mechanically inclined, understanding how Infiniti cars are engineered, and especially how they relate back to their Nissan counterparts, is crucial. This article will dive into the technical aspects of Infiniti vehicles, providing a solid foundation for repairs, modifications, and general automotive knowledge.

Purpose: Understanding Infiniti's Engineering

Why should you care about understanding Infiniti's engineering? Several reasons:

Repairs and Maintenance: Knowing the shared components with Nissan vehicles can save you money on parts and labor. You might find a comparable Nissan part for a fraction of the cost of an Infiniti-branded one.

Modifications: Understanding the underlying platform allows for informed modifications. You can leverage Nissan aftermarket parts or adapt them for Infiniti applications.

Diagnostics: A solid understanding of the electrical and mechanical systems helps you diagnose problems more accurately and efficiently.

General Automotive Knowledge: Expanding your knowledge base makes you a more informed car owner and DIY mechanic.

Having access to detailed diagrams, schematics, and technical manuals is invaluable for these purposes. We'll touch on where you can get access to these later. For now, let's dive into the specifics.

Key Specs and Main Parts

Infiniti, while offering a distinct luxury experience, shares many core components with Nissan vehicles. Here's a breakdown, focusing on similarities and differences:

Engines:

Infiniti often uses upgraded or modified versions of Nissan engines. Consider these examples:

VQ-Series: The VQ35DE and VQ37VHR engines are staples in both Nissan and Infiniti models. Infiniti versions often feature higher compression ratios, revised intake manifolds, and enhanced engine management systems for increased power and torque. The VQ37VHR, for instance, features Variable Valve Event and Lift (VVEL) technology, which provides more precise control over valve timing and lift for improved performance and fuel efficiency. Nissan also used VVEL but often in different applications or states of tune.

VR-Series: More recently, Infiniti has adopted the VR30DDTT twin-turbo V6, also found in the Nissan Z. This engine represents a significant step forward in performance and technology. It utilizes direct injection and advanced turbocharger design for efficient power delivery.

Transmissions:

Like the engines, transmissions also have common origins, but Infiniti often employs more advanced or refined versions.

Automatic Transmissions: Many Infiniti models use Jatco-sourced automatic transmissions, which are also found in Nissan vehicles. However, Infiniti often has different tuning parameters and shift strategies for a more luxurious driving experience.

Manual Transmissions: Some Infiniti models, particularly those aimed at performance, have offered manual transmissions, often shared or derived from Nissan units but optimized for higher power output and improved shift feel.

Chassis and Suspension:

The underlying chassis architecture often shares similarities with Nissan platforms, but Infiniti adds significant refinements to enhance handling and ride quality.

Suspension Components: Infiniti often uses more advanced suspension designs, such as multi-link setups, and incorporates features like electronically adjustable dampers and adaptive suspension systems for superior handling and comfort.

Braking Systems: Infiniti vehicles typically have larger brake rotors and calipers compared to their Nissan counterparts, providing improved stopping power and heat dissipation.

Electronics:

Infiniti’s electronics are usually more sophisticated than what you would find on a Nissan of the same year. These upgrades include premium audio, more advanced safety features, and upgraded navigation.

ECU (Engine Control Unit): Even though the engine blocks themselves may be similar to Nissan blocks, the ECU programming can have significant differences. This is due to Infiniti wanting a more ‘spirited’ driving experience in most of their models.

Symbols: Interpreting Diagrams and Schematics

Understanding the symbols used in automotive diagrams and schematics is essential for effective troubleshooting and repair. Here are some common symbols you'll encounter:

Lines: Solid lines typically represent wires or fluid lines. Dashed lines may indicate vacuum lines or control signals. Different colors often denote different circuits or fluid types (e.g., red for power, blue for coolant).

Resistors: Represented by a zig-zag line. These components limit current flow in a circuit.

Capacitors: Shown as two parallel lines. These store electrical energy.

Diodes: Displayed as a triangle pointing to a vertical line. Diodes allow current to flow in only one direction.

Relays: Depicted as a coil with a switch. Relays use a small current to control a larger current circuit.

Sensors: Varied symbols depending on the sensor type (e.g., temperature, pressure, speed). Often shown with an arrow indicating the parameter being measured.

Color coding is also crucial. For example:

Red: Typically indicates a positive power supply (e.g., +12V).

Black: Usually represents ground or negative connections.

Other Colors: Represent specific circuits or signals, such as sensor outputs, control signals, or communication lines (e.g., CAN bus).

How It Works: Interconnected Systems

Modern cars are complex networks of interconnected systems. Understanding how these systems interact is vital for effective diagnostics and repair. Here's a simplified overview:

Engine Management System: Controls fuel injection, ignition timing, and other engine parameters based on sensor inputs. The ECU processes data from sensors like the mass airflow sensor (MAF), oxygen sensors (O2), and crankshaft position sensor (CKP) to optimize engine performance and emissions.

Transmission Control System: Manages gear shifting in automatic transmissions. The Transmission Control Module (TCM) receives data from various sensors and the ECU to determine the optimal shift points and ensure smooth gear changes.

Braking System: Includes components like the master cylinder, brake lines, calipers, and rotors. Anti-lock braking systems (ABS) use sensors to detect wheel lockup and modulate brake pressure to maintain traction.

Steering System: Can be either hydraulic or electric power-assisted. Electric power steering (EPS) systems use an electric motor to assist steering, controlled by the ECU based on vehicle speed and steering input.

Body Control System: Manages various functions like lighting, windows, and door locks. The Body Control Module (BCM) controls these functions based on input from switches and sensors.

Real-World Use: Basic Troubleshooting Tips

Here are some basic troubleshooting tips for common Infiniti issues, keeping in mind the shared Nissan heritage:

Check Engine Light: Use an OBD-II scanner to retrieve diagnostic trouble codes (DTCs). Research the codes and related symptoms to identify the potential cause. Many Nissan forums can provide insight into common issues and solutions.

Starting Problems: Check the battery voltage, starter motor, and ignition system. A weak battery or faulty starter can prevent the engine from starting. Inspect spark plugs and ignition coils for signs of wear or damage.

Poor Performance: Investigate the air intake system, fuel system, and exhaust system. A clogged air filter, faulty fuel pump, or restricted exhaust can reduce engine power.

Braking Issues: Inspect brake pads, rotors, and brake lines. Worn brake pads or warped rotors can cause poor braking performance. Check for leaks in the brake lines and master cylinder.

Suspension Noises: Inspect suspension components like shocks, struts, ball joints, and bushings. Worn or damaged components can cause clunking or squeaking noises.

Safety: Highlighting Risky Components

Working on cars involves inherent risks. Always prioritize safety and take necessary precautions. Here are some components that require extra caution:

High-Voltage Components: Hybrid and electric vehicles contain high-voltage batteries and components that can deliver a lethal shock. Always disconnect the high-voltage system and follow proper safety procedures before working on these vehicles.

Fuel System: Gasoline is highly flammable. Always disconnect the fuel pump and relieve fuel pressure before working on the fuel system. Avoid sparks or open flames near fuel lines or components.

Airbags: Airbags are explosive devices. Always disconnect the battery and wait at least 10 minutes before working near airbags. Handle airbags carefully to avoid accidental deployment.

Brake System: Brake fluid is corrosive. Avoid contact with skin and eyes. Dispose of used brake fluid properly.

Always wear appropriate safety gear, including eye protection, gloves, and sturdy shoes. Use jack stands to support the vehicle when working underneath it. Follow manufacturer's instructions and consult repair manuals when performing any maintenance or repair procedure.

You're now better equipped to understand the engineering of Infiniti vehicles and how they relate to their Nissan counterparts. Remember, this is a starting point. Continuous learning and hands-on experience are essential for mastering automotive mechanics.

And to help you in your endeavor, we have diagrams and schematics available to download. Please reach out and we can make these resources available to you.