Why <em>Nissan Almera Classic</em> does not start when cold: diagnostics and repair

Nissan Almera Classic (also known as Nissan Sunny B10 in some markets) is a reliable sedan with a simple design, but even it is not immune to cold start problems. Owners often encounter a situation where the car refuses to start after being parked overnight or in cold weather, but during the day or when warm it starts without problems. In 80% of cases, it is not engine breakdowns that are to blame, but wear and tear of consumables or electronics failures.

In this article we will analyze 7 main reasonswhy Almera Classic does not start when cold - from a dead battery to malfunctions coolant temperature sensor (DTOZH). For each problem we give symptoms, diagnostic methods and step-by-step instructions for elimination, including budget solutions (for example, how to “reanimate” a starter without replacement). We will pay special attention specifics of the model with engines QG15DE And QG18DE, where the fuel injectors and throttle body are most often affected.

1. Discharged or “tired” battery

The most obvious but often ignored reason. In the cold Almera Classic requires 30–40% more current for cranking the starter than with a warm start. If the battery is worn out or undercharged, its capacity may only be enough for weak rotation of the crankshaft - or for relay clicks.

How to check:

• 🔋 Terminal voltage with the ignition off: there should be 12.6–12.8 V. If below 12.2 V - the battery is low.
• 🔌 Voltage under load (when cranking the starter): should not fall below 9.5 V. If it falls to 7–8 V - The battery is “dead”.
• 🕒 Battery age: If the battery is more than 4-5 years old, its capacity may have dropped by 50% even at normal voltage.

Solutions:

• ⚡ Charge the battery electric shock 2–3 A for 10–12 hours (not fast charging!).
• 🔄 Clean the terminals from oxides and check the fit.
• 🔋 Replace the battery, if it is older than 5 years or does not hold a charge. For Almera Classic Suitable battery capacity 55–60 Ah with starting current not less 500 A.

⚠️ Attention: If the battery discharges quickly after charging (overnight), check leakage current multimeter. Normal - no more 50 mA. Excess indicates a “gluttonous” alarm or a short circuit in the on-board network.

2. Starter malfunctions: from brushes to bendix

Starter on Almera Classic - a weak point, especially after 150–200 thousand km. Typical symptoms of its malfunction when cold:

• 🔊 Clicks When I turn the key, the engine does not turn over.
• 🐢 Slow rotation crankshaft (as if “for wear”).
• 🔥 Burning smell from under the hood after several attempts to start.

Causes and diagnosis:

Malfunction	Signs	How to check
Brush wear	The starter turns jerkily or does not turn at all	Remove the starter and measure the length of the brushes (the norm is from 12 mm)
Bendix problems	Characteristic metallic grinding noise upon startup	Turn the bendix manually - it should rotate in one direction only
Burnt contacts of the solenoid relay	Clicks without scrolling or smell of burning plastic	Test the relay with a multimeter (winding resistance - 0.5–1 Ohm)

Budget renovation:

• 🔧 Cleaning contacts solenoid relay with sandpaper (P600).
• 🛠️ Replacing brushes (the set costs ~500 rubles).
• 🔄 Bendix lubrication lithol (if it jams).

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

In the cold Almera Classic Particularly sensitive to fuel quality and the condition of the fuel system. If the engine QG15DE/QG18DE does not start, but the starter turns vigorously, the culprits are:

• 🛢️ Weak fuel pump (does not create the required pressure).
• 🔥 Clogged injectors (especially if the car has been sitting for more than a week).
• ❄️ Frozen water in the fuel line (relevant for regions with sub-zero temperatures).

How to diagnose:

1. Check the fuel rail pressure:
   • Connect the pressure gauge to the fitting on the ramp (standard for Almera Classic — 2.8–3.2 kg/cm²).
   • If the pressure is lower 2 kg/cm² - the fuel pump or pressure regulator is at fault.
2. Listen to the pump:
   • When you turn on the ignition, there should be a distinct hum from under the rear seat (where the pump is located).
   • If there is no sound, check the fuse F15 (15A) and fuel pump relay.

Quick solutions:

• ⛽ Add injector cleaner (For example, Liqui Moly Injection Reiniger) into fuel.
• 🔥 Warm up the fuel rail hairdryer (if you suspect ice in the line).
• 🔧 Check the fuel pump grid — its clogging leads to “starvation” of the engine.

⚠️ Attention: If after a long period of inactivity (Almera Classic stood for more than a month) the engine does not start, do not turn the starter for more than 10 seconds at a time. This may flood the candles. It’s better to unscrew them and check for the presence of gasoline (if they are wet, dry them or replace them).

4. Sensor malfunctions: DTOZH, mass air flow sensor, crankshaft sensor

Electronics Almera Classic sensitive to sensor readings, especially when cold. If at least one of them is lying, the ECU may incorrectly calculate the composition of the fuel mixture or ignition timing.

Top 3 “problem” sensors:

1. Coolant temperature sensor (DTOZH):
   • If it shows -40°C at real temperature +5°C, The ECU enriches the mixture and fills the spark plugs.
   • How to check: Measure the resistance of the sensor at different temperatures (at 20°C must be~2–3 kOhm).
2. Mass air flow sensor (MAF):
   • If there is a malfunction, the engine may stall immediately after starting or run intermittently.
   • How to check: Disconnect the mass air flow sensor connector - if the car starts, the sensor is faulty.
3. Crankshaft position sensor (CPS):
   • If it fails, the engine will not start at all (there is no signal about the position of the pistons).
   • How to check: Ring the sensor winding (resistance - 550–750 Ohm).

Advice: If there is no time for diagnostics, reset the ECU errors by disconnecting the battery terminal for 10 minutes. Sometimes this helps to “reboot” the system and start the engine.

How to deceive the ECU if the DTOZH is lying?

If the temperature sensor shows incorrect values, you can temporarily connect a resistor to 2.7 kOhm between the signal wire and ground. This simulates the temperature~20°C, and the ECU will calculate the mixture correctly. But this solution is only for emergency cases!

5. Flooded spark plugs: how to dry them and avoid recurrence

If Almera Classic does not start when cold, but after several attempts it “catch” and starts working intermittently, it’s the fault flooded candles. This happens due to:

• 🔥 rich mixture (DTOZh or lambda probe is to blame).
• 🛢️ Bad fuel (with impurities or low octane number).
• ⚡ Weak spark (worn spark plugs or armored wires).

How to dry candles without removing them:

1. Depress the gas pedal all the way and crank the starter for 5-10 seconds. This will shut off the fuel supply (purge mode).
2. Wait 2-3 minutes and restart without pressing the gas.
3. If that doesn’t help, unscrew the candles, dry them with a hairdryer or on the stove (do not overheat!) and clean them with a brush.

Prevention:

• 🔧 Change the spark plugs every 30–40 thousand km (for Almera Classic fit NGK BCPR6ES or Denso K16PR-U11).
• ⛽ Refuel at trusted gas stations — cheap gasoline often contains additives that fill the spark plugs.
• 📉 Monitor the oil level - if it gets into the combustion chambers (through the valve stem seals), the spark plugs quickly fail.

6. Problems with alarm and immobilizer

On Almera Classic (especially with alarms StarLine or Alligator) the immobilizer or start lock often fails due to:

• 🔑 Discharged key fob (even if the car opens, the signal may not pass through).
• 📡 Interference from other devices (for example, if there is a car nearby with a working alarm).
• 🔧 Oxidized contacts in the immobilizer unit (located under the dashboard).

How to diagnose:

• 🔍 Look at the immobilizer lamp (key icon on the dashboard). If it flashes or stays on, the system is blocking startup.
• 🔑 Try starting the car with the second key (sometimes the chip in the main key fails).
• 📱 Turn off the alarm emergency button (usually hidden under the dashboard or in the glove compartment).

Emergency measures:

• 🔧 Reset the immobilizer unitby disconnecting the battery for 15–20 minutes.
• 🔑 Rewrite the keys to the service station (if the problem is in the chip).
• 🚗 Tow the car to a warm box — sometimes the immobilizer is triggered due to low temperature (condensation on the boards).

7. Mechanical problems: compression, timing belt, valves

If all the previous steps did not help, the problem may be mechanical part of the engine. Especially noticeable in cold weather:

• 🔧 Low compression (wear of piston rings or valves).
• 🔄 Timing belt slippage (for 1–2 teeth).
• 🚪 Valve clearances (on QG15DE/QG18DE require adjustment every 90 thousand km).

How to check compression:

1. Unscrew all spark plugs.
2. Insert the compression gauge into the first cylinder and crank the starter for 5–7 seconds.
3. Record the readings and repeat for the remaining cylinders.
4. Norm for Almera Classic: 12–14 kg/cm² in each cylinder, spread between cylinders - no more 1 kg/cm².

What to do if compression is low:

• 🛢️ Fill the cylinders with oil (5–10 ml each) and repeat the measurement. If the compression has increased, the rings are worn out; if not, the problem is in the valves.
• 🔧 Adjust the valves (gaps: intake - 0.20 mm, graduations - 0.30 mm).
• 🔄 Check the timing belt for matching marks. If the belt slips, the engine will not start at all.

⚠️ Attention: If the compression in one of the cylinders is lower 8 kg/cm², exploit Almera Classic you can't - it will lead to breakdown of the cylinder head gasket or scoring on the cylinder walls.

FAQ: Frequently asked questions about cold starts Nissan Almera Classic

❓ Why does the car only start from “push” to cold?

This indicates starter problems (does not turn) or strong enrichment of the mixture (fills the candles). If it starts easily with the pushrod, check:

• Battery (there may not be enough current for the starter).
• DTOZH (if it’s lying, the ECU is pouring too much fuel).
• Injectors (may “overflow” due to clogging).

❓ Is it possible to drive if the car doesn’t start the first time?

Short term - yes, but this makes the problem worse. For example:

• If the candles are to blame, they flood even more.
• If the problem is in the starter, it overheats and fails.
• If the fuel pump is at fault, its service life is reduced due to wear and tear.

It is better to eliminate the cause than to wait until the car it won't start at all.

❓ What kind of gasoline should I use to avoid starting problems?

For Almera Classic with engines QG15DE/QG18DE gasoline is optimal AI-95 from trusted networks (Lukoil, Gazpromneft, Rosneft). Why not 92?

• 92 gasoline evaporates faster in the cold, which leads to enrichment of the mixture and pouring candles.
• 95 gasoline contains more additives, which prevent the formation of condensation in the fuel system.

If you have to pour 92, add injector cleaner (for example, Hi-Gear HG3201).

❓ How much does diagnostics cost at a service station?

The cost depends on the depth of the inspection:

Type of diagnosis	Cost (₽)
Computer diagnostics (scanner)	800–1 500
Compression check	500–1 000
Starter/generator diagnostics	1 000–1 800
Complete fuel system check	1 500–2 500

Tip: If your budget is limited, start with self-checking of batteries, spark plugs and DTOZh - it's free and solves 50% of problems.

❓ Is it possible to have Almera Classic from a tow if the starter does not work?

Yes, but with reservations:

• 🚗 Only on mechanics (automatic cannot be towed!).
• 🔧 Engage 2nd or 3rd gear (not the first, so as not to hit the transmission).
• 🛑 Don't gas When towing, accelerate smoothly to 20–30 km/h, then release the clutch.

⚠️ Dangerous: If the problem is a broken timing belt, towing can bend the valves!