Exhaust system <em>Nissan Almera G15</em>: diagram, design and repair

Nissan Almera G15 is a popular sedan known for its reliability and unpretentiousness. However, even in such cars, the exhaust system requires attention: corrosion, mechanical damage or wear of elements can lead to serious problems. In this article we will look at detailed diagram of the exhaust system, we’ll talk about the functions of each unit, typical faults and repair nuances.

Feature Almera G15 (2012–2018) - exhaust system design adapted to environmental standards Euro-4/Euro-5. This means the catalytic converter, lambda probes and resonators are often the source of problems. If you hear a loud roar under the hood, smell exhaust fumes in the cabin, or notice black carbon deposits at the end of the muffler, it’s time to understand the system.

Exhaust system design Nissan Almera G15: basic elements

Exhaust system Almera G15 consists of several key nodes, each of which performs its own function. Below is element layout diagram (from engine to exhaust pipe):

• 🔥 Exhaust manifold - the first element that receives hot gases from the cylinders. On Almera G15 it is integrated with the catalyst (depending on modification).
• 🔄 Catalytic converter — cleans the exhaust from harmful substances (CO, CH, NOx). On models with 1.6 HR16DE a two-section catalyst is installed.
• 📊 Lambda probes (oxygen sensors) — control the composition of exhaust gases. On Almera G15 there are two of them: upper (before the catalyst) and lower (after).
• 🔇 Front and rear mufflers - reduce noise. The system also has resonator (intermediate muffler).
• 🚗 Exhaust pipe with tip - the final element that removes gases outside the car.

It is important to understand that the design may vary slightly depending on the year of manufacture and the market. For example, on models for Russia and CIS a simplified system was often installed without an additional resonator, and European versions were equipped with more complex catalysts.

Exhaust system diagram Nissan Almera G15 with catalog numbers

To accurately select spare parts for repairs, it is important to know the original catalog numbers. Below is a table with the main elements and their part numbers for the engine 1.6 HR16DE (most common option):

System element	Original number	Analogs (popular brands)	Notes
Exhaust manifold with catalyst	20060-4M50A	Bosch 0986AG0010, Walker 70316	Often fails due to overheating
Front muffler (resonator)	20510-4M50A	SASIC 50114, Eberspächer 713546	Corroded at the bottom
Rear muffler	20520-4M50A	Magneti Marelli 145300340000, Klarius 562-1015	May require replacement every 80–100 thousand km
Lambda probe (upper)	22690-4M50A	NGK 91819, Denso DOX-0108	Service life - 60–80 thousand km
Lambda probe (lower)	22691-4M50A	Bosch 0258006537, Delphi ES10113	Less susceptible to contamination, but also fails

Important: On vehicles with an engine 1.5 K4M (Renault) catalog numbers will be different. For example, the exhaust manifold has the article number 820063269R, and the rear muffler - 820056292R.

Typical exhaust system faults Almera G15 and their signs

Exhaust system Nissan Almera G15 is subject to several characteristic problems. Let's look at them in more detail:

• 🔥 Exhaust manifold burnout - more common on engines 1.6 HR16DE due to high temperatures. Signs: metallic knocking when warming up, loss of power.
• 🚨 Clogged catalyst - leads to an error P0420 (“low catalyst efficiency”). Symptoms: poor acceleration, increased fuel consumption, sulfur smell.
• 🔊 Burnt out muffler — a loud roar appears, especially at high speeds. The weld between the resonator and the main muffler often suffers.
• ⚡ Faulty lambda probes - errors P0130–P0167 in the ECU. Signs: unstable idle, jerking during acceleration.
• 💨 Cracks in corrugation — vibrations and corrosion lead to depressurization. Symptom: popping noises under the bottom when revving.

One of the most insidious problems is catalyst destruction. Its ceramic filling can crumble and clog the muffler, leading to a complete loss of traction. In this case, urgent replacement is required, as fragments can damage the engine cylinders.

⚠️ Attention: If the dashboard lights up Check Engine and the scanner shows an error P0420, don't ignore her! Driving for a long time with a clogged catalyst can lead to engine overheating and costly repairs.

How to diagnose exhaust system problems yourself

Many faults can be identified without visiting a service station. Here is a simple diagnostic algorithm:

1. Visual inspection. Place the car on a lift or inspection hole and check:
   • Presence of rust, cracks or holes in the mufflers.
   • The integrity of the corrugation (it should not be swollen or torn).
   • The condition of the rubber hangers is that they should not be torn.

Check for leaks. Start the engine and listen to the sounds underneath. A characteristic hissing or popping noise will indicate depressurization.

Diagnostics of lambda probes. Use a scanner (eg ELM327) to check sensor readings. The voltage on the working probe should fluctuate in the range 0.1–0.9 V.

Back pressure test. Remove the first lambda probe and measure the pressure in the system (should be no more than 0.3–0.5 kg/cm² at idle speed). Exceeding the norm indicates a clogged catalyst.

If you don't have a scanner, pay attention to indirect signs: black smoke from the exhaust pipe indicates a rich mixture (problems with sensors or injectors), white smoke - about antifreeze getting into the cylinders, blue smoke - about oil starvation.

Repair and replacement of exhaust system elements: step-by-step instructions

Many exhaust system repairs Almera G15 you can do it yourself. Let's consider replacing the most problematic elements:

1. Replacing the lambda probe

Required: key 22 mm, penetrating lubricant (WD-40), new sensor.

1. Disconnect the negative terminal of the battery.
2. Disconnect the sensor connector (press the lock).
3. Treat the threads with penetrating lubricant and unscrew the sensor.
4. Install a new probe after lubricating the threads with graphite lubricant.

2. Replacing the corrugation or muffler

You will need: an angle grinder, a welding machine (or clamps), new parts.

• 🔧 If the corrugation is torn, it can be replaced separately by cutting out the old one and welding a new one.
• 🔨 When replacing a muffler, cut off the old one along the weld seam and weld a new one.
• 🔩 An alternative to welding is to use crimp clamps (For example, Walker Exhaust Clamp).

3. Removing the catalyst (only for non-eco-friendly modifications!)

This procedure illegal in most countries, but is sometimes used when the catalyst fails. Instead they install flame arrester or stronger. After removal, ECU firmware is required Euro 2 or installing a lambda probe decoy.

⚠️ Attention: Removing the catalyst Almera G15 with engine HR16DE without updating the firmware will lead to a permanent error P0420 and increased fuel consumption (up to +2 liters per 100 km).

What happens if you ignore a catalytic converter malfunction?

Driving for a long time with a clogged catalyst leads to:

- engine overheating (risk of cylinder head deformation);

- increased pressure in the system, which can squeeze out the exhaust manifold gasket;

- penetration of ceramic dust into the cylinders, which leads to scoring on the walls and wear of the piston rings.

In critical cases, the engine may simply stall and not start again without repair.

Selection of spare parts: original vs analogues

When replacing exhaust system elements Almera G15 The question arises: what to choose - original parts or analogues? Let's look at the pros and cons of each option:

Part type	Pros	Cons	Recommendations
Original (Nissan)	Perfect compatibility, long service life, warranty	High price (for example, a muffler costs ~15,000 rubles)	Optimal for new cars or during warranty repairs
Analogs (Bosch, Walker, SASIC)	The price is 30–50% lower, good quality from trusted brands	May vary in size or material	Suitable for budget renovation
Budget analogues (no-name)	Minimum cost (muffler from ~3,000 rub.)	Low quality metal, rapid corrosion, poor sound insulation	Only as a temporary solution

When choosing analogues, pay attention to:

- material (stainless steel or aluminized coating will extend service life);

- metal thickness (thin-walled mufflers burn out in 1–2 years);

- complete set (some kits do not have fasteners).

Prevention and extension of the service life of the exhaust system

To avoid costly repairs, follow these simple recommendations:

• 🚗 Avoid driving through deep puddles. Sudden temperature changes accelerate metal corrosion.
• 🔧 Check the muffler hangers regularly. Torn rubber bands lead to vibrations and cracks.
• ⛽ Refuel with quality fuel. Bad gasoline destroys the catalyst and lambda probes.
• 🔥 Do not overheat the engine. Long-term operation at high speeds increases the load on the exhaust system.
• 🧹 Clean the underbody periodically. Salt and reagents aggressively corrode metal in winter.

Pay special attention the first sign of trouble:

- extraneous sounds (knocking, humming, popping);

- vibrations on the body when the engine is running;

- the smell of exhaust gases in the cabin (indicates a leak in front of the catalyst).

If you operate the vehicle in conditions north or high humidity, it is recommended to treat the muffler with anti-corrosion compounds once every 2–3 years (for example, Dinitrol 494 or Molykote).

Frequently asked questions (FAQ)

Is it possible to drive with a burnt out muffler?

Technically possible, but not advisable. A burnt-out muffler not only increases noise, but also allows exhaust gases to enter the cabin (risk of carbon monoxide poisoning). In addition, depressurization of the system can cause errors in engine operation due to incorrect readings from the lambda probes.

How much does it cost to replace the exhaust system on an Almera G15 at a service center?

The cost depends on the scope of work:

• Replacement of a lambda probe - from 1,500 to 3,000 rubles. (with spare part).
• Replacement of corrugation - from 3,000 to 5,000 rubles.
• Complete replacement of the system (from the manifold to the muffler) - from 15,000 to 30,000 rubles.

Welding work is paid separately (~1,000–2,000 rubles per seam).

What ECU errors are related to the exhaust system?

The most common codes:

• P0420 — low catalyst efficiency;
• P0130–P0167 - malfunction of lambda probes;
• P0430 — problems with heating the second oxygen sensor;
• P2096 — lean mixture after the catalyst (may indicate an exhaust gas leak).

For accurate diagnosis, a scanner is required (for example, Launch CReader or Autel).

What is the difference between the exhaust system of Almera G15 with 1.5 and 1.6 engines?

Main differences:

• On 1.5 K4M (Renault) the catalyst is separated from the exhaust manifold, while on 1.6 HR16DE they are united.
• Silencers have different configurations: on 1.5 the resonator is shorter and the rear muffler is longer.
• Lambda probes on 1.5 have different connectors and catalog numbers.

Spare parts not interchangeable!

Is it possible to install a sports exhaust on the Almera G15?

Technically yes, but it will require some work:

• Replacing the standard muffler with direct-flow (For example, Remus or Sprint).
• Installation spider 4-2-1 instead of a standard manifold (for an engine HR16DE).
• Reflashing the ECU for the changed system (otherwise there will be an error Check Engine).

Please note that such tuning will increase the noise (up to 90–100 dB) and can lead to problems with passing technical inspection.