The situation when the legendary Toyota Land Cruiser 105 refuses to start, always takes the owner by surprise. This car is famous for its phenomenal reliability, but even the most time-tested mechanisms have failures, especially if we are talking about a significant mileage. Most often, the problem lies not in a major engine failure, but in malfunctions of peripheral systems, which are easy to diagnose if you have basic knowledge.
Owners of diesel versions with a motor 1HZ encounter starting failures much more often than owners of gasoline modifications. This is due to the design features of the high-pressure fuel system and the quality requirements for diesel fuel. Gasoline engines 1FZ-FE Usually they please with stability, but they also have their own “childhood illnesses” associated with the ignition or fuel supply system. It is important not to panic and consistently check the main components.
Before starting an in-depth diagnosis, it is necessary to evaluate the nature of the failure: does the starter spin, is there any seizure, are the lights on the instrument panel lit. The further algorithm of actions depends on this. Ignoring the initial symptoms may result in a completely discharged battery or more serious damage to the attachment.
⚠️ Attention: If, when you turn the key, the starter does not make any sounds and the lights on the panel go out, first check the battery terminals - oxidation of the contacts is the most common cause of “imaginary” death of electronics.
Diagnostics of the starter group and battery
The first link in the starting chain is always the current source. On Land Cruiser 105 powerful starters are installed that consume huge current, so the condition battery critically important. Even if the headlights are bright, under load from the starter, the voltage may drop below the permissible minimum required for the operation of the ECU or fuel valve.
If the starter turns sluggishly, or you hear a crackling or clicking noise, the problem may lie in the starter itself. Over time in starter The brushes wear out, the solenoid relay burns out, or a short circuit occurs in the windings. It is also worth checking the engine ground, since an oxidized ground wire often causes poor electrical performance.
- 🔋 Check the voltage at the battery terminals under load - it should not fall below 9.5-10 Volts.
- 🔧 Clean the terminal contacts and check that the ground wire is securely attached to the body and engine.
- ⚙️ Listen to the sound of the starter: a smooth hum indicates normality, a metallic clang indicates a mechanical malfunction.
A weak starter simply will not be able to create the necessary compression to ignite the fuel.
Problems of the fuel system of the 1HZ diesel engine
If the electrics are in order and the starter vigorously turns the flywheel, but the engine is silent, you should look for the cause in the fuel. For motor 1HZ characterized by a mechanical fuel supply system with an in-line injection pump, which is sensitive to airing. Air getting into the system is the most common reason why Kruzak 105 won't start diesel
Air can be sucked in through cracks in the fuel hoses, through the o-rings of the fuel filter, or through the seals of the injection pump plunger pairs. As a result, instead of diesel fuel, the pump pumps an air mixture; there is not enough pressure to open the nozzles. Before starting, it is necessary to bleed the system with a manual bulb pump.
Another critical problem in winter is fuel waxing. At low temperatures, paraffin crystals form in diesel fuel, which clog the fuel intake in the tank and the fine filter. The engine may start for a few seconds with remaining fuel in the line, and then stall.
⚠️ Attention: It is strictly forbidden to try to start the engine with a “spray gun” (aerosol starter) without first checking the condition of the timing belt, since on a 1HZ engine, if the belt breaks, the valves bend.
How to quickly remove air from the system?
To remove air, loosen the bleeder screw on the fuel filter housing or on the injection pump. Pump vigorously with a hand pump until fuel comes out of the hole without air bubbles. Then tighten the screw and repeat the procedure on the injectors (loosening the high pressure pipe nuts) if the engine still does not start.
Malfunctions of the starting system of the 1FZ-FE gasoline engine
Gasoline 1FZ-FE It has distributed injection and an electronic ignition system. If this engine turns over but won't start, the spark plugs, coil or distributor are most often to blame. In conditions of high humidity (for example, after washing or rain), it can pierce high-voltage wires or the distributor cap.
It is also worth paying attention to the fuel pressure regulator. If it does not maintain pressure in the rail after stopping, then when starting, the pump takes time to pump in the required amount of gasoline. Prolonged cranking of the starter in this case can flood the spark plugs, which will ultimately prevent starting.
Checking the spark is the primary stage of diagnosis. Unscrew one spark plug, attach its thread to the engine ground and ask an assistant to turn the starter. The spark should be powerful, blue and jump consistently. A weak, yellow spark indicates problems with the coil, switch or battery.
Before checking the spark on a gasoline engine, make sure that the injectors do not pour fuel continuously, otherwise you risk starting a fire if you try to start frequently.
Effect of ambient temperature on startup
Winter launch Toyota Land Cruiser 105 - this is a separate topic for conversation. Low temperatures thicken engine oil, increasing resistance to cranking. Combined with a dead battery, this creates a critical situation. A diesel engine is especially demanding on compression temperature.
The preheating system, including glow plugs or a coil in the intake manifold (on newer versions), plays a key role. If the glow indicator on the panel goes out too quickly or does not light up at all, the relay or the spark plugs themselves may be faulty. Without heating the combustion chambers, ignition of the mixture is impossible.
The table below shows the main symptoms and their likely causes depending on the conditions:
| Symptom | Probable Cause (Diesel) | Probable Cause (Gasoline) |
|---|---|---|
| Starter turns slowly | Thickened oil, weak battery | Low battery |
| No smoke from the exhaust | No fuel supplied (air, paraffin) | No spark or gasoline |
| There is white smoke, but it won't start | There is fuel, but no ignition (plugs) | The spark plugs are flooded, the timing phases are broken |
| Starts and immediately stalls | Air leak in the line | Fuel pump does not hold pressure |
Using engine preheaters and the correct oil viscosity 5W-30 or 5W-40 Makes cold starts much easier. Do not neglect the installation of additional equipment for harsh climatic conditions.
The main enemy of a cold diesel start is not frost, but a bad battery and an airy fuel system.
Mechanical reasons for lack of compression
If the starter turns the engine with unusual ease, without characteristic resistance, this is an alarming sign. The lack of compression makes starting impossible for either diesel or gasoline. On long runs Land Cruiser 105 Troubleshooting of the cylinder-piston group may be required.
The cause of a drop in compression may be worn piston rings, burnt-out valves, or a breakdown of the cylinder head gasket. Often on 1HZ diesel engines, when overheated, the head “sits” and the valves no longer fit tightly to the seats. It is also possible for the timing belt to break, which is fatal on this engine.
- 📉 Measure the compression with a compression meter - for a diesel engine the norm starts from 25-28 atmospheres, for gasoline from 10-11.
- 💧 Check the oil level and the presence of emulsion on the dipstick or in the expansion tank.
- 🔊 Pay attention to the sound of the starter: the absence of compression strokes makes the rotation uniform and fast.
Accurate diagnosis of mechanical problems often requires removal of the cylinder head. This is a complex procedure that requires special tools and qualifications, so if you suspect a mechanic, it is better to contact a specialized service.
☑️ Minimum kit for diagnostics in the field
Electronics and sensors: hidden problems
Although Toyota Land Cruiser 105 is considered a car with a minimum amount of electronics, especially in diesel versions, certain sensors can block starting. On gasoline versions with an engine management system, the crankshaft position sensor and mass air flow sensor are critical.
On electronically controlled diesel engines (for example, EFI version 1HZ), the fuel cut-off valve on the injection pump plays an important role. If voltage does not come to it when the ignition is turned on, fuel simply will not flow to the high pressure pump. Checking that there is power to this valve is a mandatory step.
Oxidation of wiring connectors, especially in the engine compartment, often leads to unstable operation. Vibrations, moisture and temperature changes do their job. It is recommended to periodically treat the contacts with special dielectric sprays.
⚠️ Attention: When replacing sensors on a gasoline engine, be sure to reset the ECU errors, otherwise the engine may operate in emergency mode or not start correctly.Algorithm of actions in case of startup failure on the road
When Kruzak 105 does not start far from civilization, it is important to act in cold blood. Panic and chaotic actions will only drain the battery. First, visually inspect the engine compartment for obvious breaks or disconnected hoses.
Check the presence of fuel in the tank, as the level indicator may lie due to a faulty sensor or vehicle tilt. Make sure the fuel pump is running (gasoline) and you can hear a hum when you turn on the ignition. Try starting the engine with an assistant, using the “lighting” method from another car, if you have doubts about the battery.
If all else fails, and the engine is diesel, you can try to carefully introduce ether (starting fluid) into the intake manifold by removing the pipe from the air filter. However, this must be done extremely carefully so as not to damage the motor.
Can a 1HZ diesel be towed to start?
Starting a 1HZ diesel engine from a pusher or tow is extremely undesirable and dangerous. A mechanical injection pump requires a certain rotation speed to create pressure, and a sudden jerk can lead to a broken timing belt or damage to the gears. It is easier to start a petrol 1FZ-FE from a pusher, but there is also a risk of damage to the catalyst and engine.
Why does the 1HZ diesel start only with an ether mixture?
Starting on air only indicates critically low compression in the cylinders or a complete lack of fuel supply through the standard system. Ether ignites at lower pressure and temperature than diesel fuel. If the engine does not maintain compression, ether allows it to work, but such an engine cannot be operated - a major overhaul is required.
How often should glow plugs be changed?
Glow plug life Toyota Land Cruiser 105 averages 60-80 thousand kilometers, but in harsh conditions it is better to check them every autumn. A faulty spark plug not only prevents starting, but can also crumble into the cylinder, leading to costly repairs.
What should I do if after replacing the battery the car still does not start?
If the new battery is charged and in good condition, but the starter barely turns, the problem is poor terminal contact, oxidized mass, or a malfunction of the starter itself. If the starter turns vigorously, but there is no start, look for the reason in the fuel system or spark (for gasoline), since the electrical part of the start is working properly.