Nissan Almera Classic does not start well: do-it-yourself diagnostics and repairs

Owners Nissan Almera Classic (especially with engines QG15DE And QG18DE) often encounter the problem of difficult starting. The car may turn the starter but not engage, start only on the third try, or be completely silent when you turn the key. The reasons for this behavior are varied - from a banal battery discharge to serious malfunctions of the fuel system or electronics.

In this article we will look at all possible reasonswhy Almera Classic Difficult to start cold, hot or in any conditions. You will receive step-by-step diagnostic instructions, checklists for checking key components and repair tips. We will pay special attention typical "sores" of this model, which are not described in the official manuals - for example, problems with the crankshaft position sensor or air leaks through a cracked manifold.

1. Battery and electrical system: first check

If Nissan Almera Classic does not start at all (no clicks, the starter does not turn), 90% of problems are related to the battery or contacts. Even if the battery is “alive,” its voltage may drop when you try to start it, especially in winter or after a long period of inactivity.

How to check:

• 🔋 Terminal voltage no load: should be 12.6–12.8 V. When 12.0 V and below - the battery is low.
• 🔌 Terminal oxidation: White coating increases resistance. Clean with sandpaper and lubricate Lithol.
• 🔧 Engine weight: Check the wire from the negative terminal to the body and engine. Often oxidizes under the fastening bolt.
• 🚗 Starter: If you hear a metallic grinding sound when you turn the key, the bushings or bendix are worn out.

For accurate diagnostics, use a multimeter in voltage measurement mode at startup:

Parameter	Norm	Deviation
Battery voltage without load	12.6–12.8 V	Less than 12.0 V - discharge
Starting voltage	Not lower than 10.5 V	Drop to 9 V - battery is faulty
Starter voltage	11.5–12 V	Less than 10 V - poor contact
Leakage current (ignition off)	Up to 50 mA	Over 100 mA - short circuit

2. Problems with the fuel system: from the fuel pump to the injectors

If the starter turns vigorously, but the engine does not start or starts and immediately stalls - Fuel system is at fault. B Almera Classic most often suffer:

• ⛽ Gasoline pump: does not pump fuel due to worn brushes or a clogged coarse filter.
• 🔧 Fuel pressure regulator: gasoline “flows” into the return line, reducing the pressure in the rail.
• 🛢️ Injectors: clogged with deposits (especially if you refueled at dubious gas stations).
• 🚨 Fuel filter: A clogged filter creates resistance and the fuel pump cannot pump enough fuel.

How to check fuel rail pressure:

1. Connect the pressure gauge to the fitting on the ramp (on the engine QG18DE he is on the right in the direction of travel).
2. Turn on the ignition - the pressure should rise to 2.8–3.2 kg/cm².
3. Start the engine - the pressure should remain stable.
4. If the pressure drops after turning off the ignition, the fuel pump check valve.

How to temporarily start Almera Classic with a faulty fuel pump?

If the fuel pump does not pump, but you are sure that there is fuel in the tank, you can try pouring 20-30 ml of gasoline directly into the intake manifold through a hose. If the engine starts and immediately stalls, the problem is definitely in the fuel supply.

Attention! If after replacing the fuel pump Almera Classic still hard to start, check fuel pump relay (located in the fuse box under the hood). Often the relay contacts burn out and no voltage is supplied to the pump.

3. Ignition system: spark plugs, coils and high-voltage wires

If the engine Nissan Almera Classic It starts with difficulty, troits or “sneezes” when starting - the ignition system is to blame. Main problems:

• ⚡ Spark plugs: worn, oily or has incorrect clearance (0.8–1.0 mm for Almera Classic).
• 🔥 Ignition coils: insulation breakdown or winding break (especially important for motors QG18DE).
• 📡 High voltage wires: microcracks or oxidation of contacts.
• 🛠️ Crankshaft position sensor (CPS): If it is faulty, the ECU cannot generate the spark correctly.

How to diagnose:

1. Unscrew the spark plugs and inspect them:
   • 🔴 Red plaque - bad gasoline with additives.
   • ⚫ Black soot - rich mixture or oil in the combustion chamber.
   • ⚪ White coating - lean mixture or overheating.
2. Check the spark: unscrew the spark plug, put a high-voltage wire on it and apply it to ground. There should be a bright blue spark when the starter is cranked.
3. Test the ignition coils with a multimeter:
   • Primary winding resistance: 0.5–1.0 Ohm.
   • Secondary winding resistance: 5–10 kOhm.

Critical moment! If after replacing the spark plugs and coils the problem remains, Check the ECU for knock sensor errors (code P0325). In Almera Classic it often fails, and the ECU knocks down the ignition timing.

4. Sensors and ECU: hidden faults

Modern Nissan Almera Classic (even with simple engines) are equipped with many sensors on which startup depends. If at least one of them produces incorrect data, the ECU may block the start or fill the spark plugs with gasoline.

Key sensors affecting launch:

• 📊 Crankshaft position sensor (CPS): If it is faulty, the engine will not start at all.
• 🌡️ Coolant temperature sensor (DTOZH): If it breaks down, the ECU incorrectly calculates the mixture composition.
• 💨 Mass air flow sensor (MAF): If it is dirty, the engine will be difficult to start and make a loud noise.
• 🔄 Camshaft position sensor (CPR): affects valve timing.

How to check sensors without a scanner:

1. DPKV: measure the resistance between the terminals - there should be 500–700 Ohm.
2. DTOZH: cold engine resistance 2–3 kOhm, when hot - 200–300 Ohm.
3. Mass air flow sensor: disconnect the connector - if the engine starts better, the sensor is faulty.

Attention! B Nissan Almera Classic with engine QG18DE a common problem with ECU firmware. If all sensors are in good working order, but the car is difficult to start, try resetting the adaptations using a diagnostic scanner or reflash the control unit.

5. Air leaks and problems with the intake manifold

One of the most insidious malfunctions is suction of unaccounted air. The engine may start, but run unsteadily, stall or stall. B Almera Classic Most often, air is sucked in through:

• 🔧 Cracks in the intake manifold (especially at the point of attachment to the cylinder head).
• 🛠️ Intake manifold gasket — over time it becomes tanned and lets air through.
• 🚗 Vacuum hoses — fray or fly off the fittings.
• 🔥 Canister valve: If stuck open, creates a pressure imbalance.

How to find the choke:

1. Start the engine and spray with soapy water (or WD-40) suspicious places. If the speed changes, there is a leak.
2. Check with a smoke generator (the most reliable way).
3. Inspect the manifold for cracks - especially in the area of the 3rd cylinder (this is where it most often bursts).

Important! If you find a crack in the manifold, do not try to weld it - aluminum Almera Classic very thin and porous. It’s better to buy a used manifold in good condition or a new one (part number 14028-4M200 for QG18DE).

6. Mechanical faults: timing, compression, oil pump

If Nissan Almera Classic does not start, but the starter turns vigorously, and there is fuel and a spark - the problem may be mechanical part of the engine. Most often the culprits are:

• 🔄 Timing belt: If it has jumped a few teeth, the valve timing is off.
• 🛢️ Compression in cylinders: if below 10 atm, the engine will not start.
• 🔧 Oil pump: if there is no oil pressure, the engine may not start (especially true after a long period of inactivity).
• 🚨 Hydraulic compensators: If they are stuck, the valves do not close tightly.

How to check:

1. Compression: Unscrew the spark plugs and measure with a compression gauge. The spread between cylinders should not exceed 1 atm.
2. Timing belt: Remove the top cover and check the alignment of the marks on the pulleys.
3. Oil pressure: Connect the pressure gauge to the pressure sensor location. At idle speed there should be at least 0.5 kg/cm².

What to do if compression is low in all cylinders?

If the compression is below 8 atm in all cylinders, most likely the piston rings or cylinders are worn out. In this case, only major repairs will help. If there is low compression in only one cylinder, check the valves (possibly burnt out or not sealed).

Attention! If, when you try to start, white smoke (steam) comes out of the exhaust pipe and the spark plugs are wet, this is a sign antifreeze getting into the cylinders. Immediately stop trying to start the engine and check the cylinder head gasket!

7. Immobilizer and alarm: start blocking

If Nissan Almera Classic won't start, but all systems are working - fault immobilizer or alarm. Most often, problems arise after:

• 🔑 Removing/installing the battery (immo settings are lost).
• 🚗 Installation of abnormal alarm systems (poorly connected interlocks).
• 🔧 Replacement of the ECU or ignition key.
• 📡 Moisture gets into the immobilizer unit (located under the dashboard on the driver’s side).

How to diagnose:

1. Look at the immobilizer lamp (yellow key on the dash). If she flashing — immo does not recognize the key.
2. Try starting the car with the second key.
3. If the alarm goes off when you try to start, check the hood and trunk switches.
4. Turn off the alarm (by removing the fuse) and try starting it.

Critical advice! If the immobilizer has blocked starting and there is no spare key, do not try to “deceive” it by turning off the power - this can lead to complete blocking of the ECU. Contact an auto electrician with a programmer to reset the immo.

FAQ: Frequently asked questions about launching Nissan Almera Classic

Why does Almera Classic start only on the third try?

This is a typical symptom air leak or faulty mass air flow sensor. During the first two attempts, the ECU “does not understand” how much air is entering the engine and incorrectly calculates the fuel mixture. On the third attempt, it accidentally “hits” the required parameters.

Also check Idle air regulator (IAC) - if it is dirty, the engine may stall immediately after starting.

The car starts and immediately stalls. What is the reason?

There are several reasons:

1. Idle air valve (IAC) is faulty — does not hold speed.
2. Injectors clogged — the fuel does not spray, but flows in a stream.
3. Air leaking through a crack in the manifold.
4. Throttle position sensor (TPS) is faulty.

Start by cleaning the IAC and throttle body.

The starter turns, but the engine does not catch. What to do?

Check:

1. Spark on the candles - if not, the problem is in the coils or the ECU.
2. Fuel rail pressure - if not, the fuel pump or relay is to blame.
3. Timing marks - if the belt has jumped, the engine will not start.
4. DPKV - if it is faulty, the ECU will not give the injection command.

After washing the engine Almera Classic does not start. What to do?

Most likely, water got into:

• 🔌 Sensor connectors (DPKV, DMRV, DPS).
• 🔋 Candle wells — if water gets on the coils, there may be a breakdown.
• 📡 Control unit (ECU) - if it is flooded, the car will not start.

Dry the engine with a hairdryer, clean the contacts WD-40 and check for spark.

Which fuel pump is better to install on Almera Classic?

Original fuel pump number for Nissan Almera Classic — 17040-4M200 (for QG18DE) or 17040-4M205 (for QG15DE).

Analogues:

• Bosch 0 580 454 035 - reliable, but expensive.
• Denso 950-0101 — good quality, average price.
• Sectron SP1105 - budget option.

When replacing the fuel pump, be sure to change coarse filter mesh and check the tightness of the fuel lines.