The situation when your Mitsubishi Lancer 9 It takes a long time to turn the starter or starts only on the second try, familiar to many owners of this legendary model. The Japanese reliability of the body and suspension often contrasts with the vagaries of the fuel system and electrics, especially when the mileage exceeds 150 thousand kilometers. The driver may encounter this in the morning in the cold or after a short stop at the store, when the engine is already warmed up.
Ignoring this symptom is dangerous because difficult starting often becomes a harbinger of more serious breakdowns that can immobilize the car at the most inopportune moment. The reasons may lie in a banal discharged battery or in a complex malfunction of the engine management system. Understanding the nature of the problem will allow you to save significant money on diagnostics in the service.
In this article, we will examine in detail the main components that affect the start of the 1.6-liter engine, which is the most common in our market. We will cover the mechanical and electrical aspects of the operation fuel system, and also pay attention to the ignition system. A competent approach to diagnostics will help you quickly regain confidence in your car.
Problems with the fuel system and fuel pump
One of the most common reasons why Lancer 9 It starts poorly, due to a drop in pressure in the fuel rail. After turning off the engine, fuel should not flow back into the tank, but over time check valve the fuel pump loses its seal. The fuel runs out and the pump takes time to build up the required injection pressure again. This phenomenon is especially noticeable after a long stay.
If the car sits for several hours, the gasoline drains and requires a long cranking of the starter to start. The driver may notice that the engine catches on the first try, but immediately stalls, and from the second start it works normally. Also worth checking fuel filter, which in this model is often clogged with dirt and rust from the tank, creating additional resistance to flow.
How to check rail pressure without a pressure gauge?
If you do not have a special pressure gauge, you can use the indirect method. After a long period of parking, before turning on the starter, turn the ignition on and off several times (3-4 times) without starting the engine. When the ignition is turned on (ON position), the fuel pump runs for several seconds. If after such a procedure the car starts instantly, then the problem is precisely the pressure drop (fuel drainage) in the system.
Don't forget that the quality of fuel varies greatly between gas stations. Using gasoline with an octane rating lower than recommended or having water in the tank may cause problems. In winter, condensation in the tank is a common reason why Mitsubishi refuses to start.
⚠️ Attention: Do not try to start the engine continuously for more than 10 seconds. This can lead to overheating of the starter and deep discharge of the battery. Pause between startup attempts.
Malfunctions of the ignition system and spark plugs
The second group of reasons why engine It starts with difficulty and is related to the quality of the spark. Spark plugs are a consumable item, and their condition directly affects the ignition of the mixture. On Lancer 9 with a 4G18 engine, it is recommended to change spark plugs every 30 thousand kilometers, although many people drive longer, which leads to starting problems.
Carbon deposits on the electrodes, an increased gap or breakdown of the insulator lead to the fact that the spark becomes weak or disappears altogether. This is especially critical in wet weather or at low temperatures, when a powerful spark is required to ignite the rich mixture. Also worth checking high voltage wires and the ignition coil for breakdowns and cracks.
If you unscrew the spark plug and it is wet with gasoline, this may indicate that the mixture is over-rich or there is no spark. Black deposits indicate a rich mixture or problems with the intake system. White deposits are a sign of overheating or a lean mixture. Analysis of the condition of the spark plugs provides a primary understanding of the processes occurring inside the cylinders.
When replacing spark plugs on Lancer 9, be sure to check the gap between the electrodes. For 4G1 series engines, a gap of 0.7-0.8 mm is considered optimal. Too large a gap will increase the load on the coil, and a small gap will worsen the ignition quality.
ECU sensors: DPKV, DMRV and idle air regulator
The electronic control unit (ECU) makes decisions based on the readings of many sensors. If crankshaft position sensor (DPKV) fails or is dirty, the control unit may simply “not know” when to supply a spark and fuel. This is one of the most insidious malfunctions, since it can manifest itself in different ways: today the car starts, but tomorrow it doesn’t.
The mass air flow sensor (MAF) also plays a key role. If it is dirty or malfunctioning, the ECU incorrectly calculates the amount of air entering the engine and forms an incorrect fuel-air mixture. If the mixture is too lean or too rich, Mitsubishi Lancer 9 It will not grip well, especially when cold.
The idle air control (IAC) is responsible for stabilizing the speed during startup and warming up. If its rod is contaminated with carbon deposits or is jammed, the engine may stall immediately after starting or require constant accelerating with the accelerator pedal. Cleaning the IAC is one of the simplest and most effective maintenance procedures.
- 🔌 DPKV: Check the integrity of the wiring and the absence of metal shavings at the end of the sensor.
- 🌬️ DMRV: Try removing the chip from the sensor; if starting improves, the sensor is faulty or dirty.
- ⚙️ RXX: Regular cleaning with special aerosols prolongs the life of the unit.
Mechanical problems and cylinder compression
If the electrical and fuel are in order, it is worth thinking about the mechanical part of the engine. Low compression - this is a sure sign of wear on the piston group, stuck rings or problems with the valves. 4G18 series engines installed on Lancer 9, are famous for their survivability, but after a mileage of 300+ thousand kilometers, wear becomes noticeable.
Compression testing is a mandatory procedure when searching for the causes of poor starting. A spread of readings between cylinders of more than 1 atmosphere or values below 10-11 bar indicates the need for serious repairs. Often the cause of a drop in compression is carbon deposits on the valves, which prevents them from closing tightly.
It is also worth paying attention to the valve timing. If the timing belt has been replaced incorrectly and is misaligned by even one tooth, the engine will run erratically and have difficulty starting. The marks on the pulleys must strictly coincide with the marks on the block and cylinder head.
⚠️ Attention: Before measuring compression, make sure the battery is fully charged. A weak starter will spin the engine at different speeds, which will distort the compression gauge readings.
Effect of temperature and battery condition
Drivers often forget that for a high-quality start, you need not only a spark and gasoline, but also a sufficient crankshaft rotation speed. Weak battery is not able to spin the starter to the required speed, especially in winter, when the oil is thick. On Lancer 9 the starter is not located in the warmest place, and at low temperatures the load on the battery increases many times over.
Oxidized terminals and poor engine ground also contribute. Over time, the contacts become coated with oxides, which act like a diode, passing current only in one direction or creating high resistance. Checking the voltage under load is the first step in diagnosing cold starting problems.
In winter, the condition of the air filter is also important. If it is clogged with snow or ice, the engine will choke. Sometimes the cause is condensation in the exhaust system, which freezes in the muffler, creating back pressure and preventing the engine from breathing out.
☑️ Winter startup diagnostics
Table of Symptoms and Probable Causes
To simplify diagnostics, we have compiled a table that will help compare the behavior of your car with the most likely malfunction. Remember that one symptom can indicate several different problems, so a comprehensive approach is important.
| Symptom | Probable Cause | Scan priority |
|---|---|---|
| Starts only with the gas pedal | IAC malfunction or air leak | High |
| Twists for a long time, then grabs it | Pressure drop in the fuel rail | Medium |
| Stalls immediately after starting | Throttle Position Sensor (TPS) | Medium |
| Doesn't start well when hot | Coolant temperature sensor or vapor lock | Low |
| Troits after launch | Breakdown of spark plugs or coils | High |
Frequently asked questions from Lancer 9 owners (FAQ)
Why does Lancer 9 start and immediately stall?
Most often this is due to an idle air control (IAC) that is dirty and cannot hold the desired speed, or a faulty throttle position sensor. It is also worth checking for leakage of unaccounted air through cracks in the pipes.
Can bad gasoline cause a long startup time?
Absolutely. Low octane number or the presence of water in the fuel disrupts the combustion process. Engine 4G18 quite sensitive to the quality of the mixture. In this case, it is recommended to drain the fuel and replace the filters.
How often do you need to change the fuel filter on Lancer 9?
Official regulations may indicate large intervals, but taking into account the quality of fuel in the regions, fuel filter It’s better to change it every 30-40 thousand kilometers. This is a cheap unit that saves the expensive fuel pump and injectors.
Does the timing belt affect starting quality?
The belt itself has no effect if it is intact. But if it is stretched or jumps onto a tooth, the valve timing is disrupted. In this case, the valves open at the wrong moments, compression drops, and the engine starts extremely difficult or does not start at all.
Solving the launch problem Mitsubishi Lancer 9 requires consistent exclusion of causes. Start with simple things: candles, filters and battery charging. If this does not help, proceed to measuring fuel pressure and compression. Systematic approach will allow you to find the fault faster and cheaper than chaotically replacing parts.
The main cause of problems with starting a used Lancer 9 is complex: a combination of a worn fuel pump, old spark plugs and a dirty throttle. Change consumables on time to avoid surprises.