Buy Mitsubishi 2.0L I4 MIVEC Turbo (4B11T) Petrol Engine - 12 Month Unlimited Mileage Warranty

🛠️ What Happens: A distinctive rattling or ticking sound is heard from the front of the engine, particularly on a cold start. This can indicate a stretched timing chain or a failing hydraulic tensioner.

⚠️ Root Cause: The hydraulic timing chain tensioner can fail to hold pressure, especially after the engine has been sitting for some time. Over time, the timing chain itself can stretch, leading to incorrect timing and potential engine damage if left unresolved.

🔧 Immediate Fix: Replace the timing chain, guide rails, and the hydraulic tensioner. It is a critical repair to prevent catastrophic engine failure due to a snapped chain or jumping timing.

💡 Prevention: Adhere to a strict oil change schedule using high-quality synthetic oil (5W-30 or 5W-40). Regular oil changes ensure the hydraulic tensioner operates correctly and reduces wear on the chain.

🛠️ What Happens: During acceleration, especially under heavy load, the revs will rise without a corresponding increase in speed. This indicates the clutches are slipping and not fully engaging, often accompanied by a "Service Required" message on the dash.

⚠️ Root Cause: The SST (Twin Clutch SST) gearbox clutches wear over time, but this issue is accelerated by hard launches, aggressive driving, or a poorly maintained transmission with old fluid. Tuned engines with high torque outputs can also overwhelm the stock clutch pack.

🔧 Immediate Fix: A clutch pack replacement is required, which is a specialised job. In some cases, a performance clutch pack may be fitted to handle higher torque. A full gearbox service and fluid replacement is essential.

💡 Prevention: Adhere to the manufacturer’s recommended service interval for the SST gearbox fluid and filter (typically every 30,000 miles). Avoid excessive hard launches and high-torque loads without proper gearbox tuning.

🛠️ What Happens: The car experiences a loss of power or "limp mode," often with an engine management light and codes relating to boost pressure control (e.g. P2563). You may also notice a rattling sound from the turbocharger at certain engine speeds.

⚠️ Root Cause: The wastegate actuator arm and linkage can corrode or become stuck due to heat cycling and carbon build-up, preventing it from opening and closing correctly. This leads to erratic boost control and performance issues.

🔧 Immediate Fix: Lubricate the wastegate actuator and linkage with a high-temperature lubricant. In severe cases, the turbocharger may need to be removed for a full strip-down and cleaning, or even replacement if parts are seized.

💡 Prevention: Regular visual inspections of the turbocharger and wastegate can catch early signs of corrosion. A performance exhaust can also reduce back pressure, which helps to keep the wastegate moving freely.

🛠️ What Happens: The engine may run rough, have a lumpy idle, and experience a noticeable loss of power at various RPMs. An engine management light will likely appear with a P0011 (intake) or P0021 (exhaust) code.

⚠️ Root Cause: The MIVEC (Mitsubishi Innovative Valve Timing Electronic Control) oil control solenoids can become clogged with debris or sludge from dirty engine oil, preventing them from correctly adjusting the camshafts. This can also lead to a failure of the solenoid itself.

🔧 Immediate Fix: The failed solenoid(s) will need to be replaced. It is also highly recommended to flush the engine oil and replace the filter to remove any contamination that may have caused the initial failure.

💡 Prevention: Adhere to a strict oil change schedule (5,000-7,500 miles) using high-quality synthetic oil. Using a quality oil filter will also help to prevent debris from reaching the sensitive solenoid valves.

🛠️ What Happens: The engine consumes an excessive amount of oil between service intervals, requiring frequent top-ups. This is often accompanied by a blueish smoke from the exhaust, especially under acceleration.

⚠️ Root Cause: Common causes include worn piston rings, faulty valve stem seals, or a failing PCV (Positive Crankcase Ventilation) valve. High boost pressures can also push oil past worn seals.

🔧 Immediate Fix: A compression test and leak-down test can help diagnose the root cause. Depending on the results, a full engine rebuild may be required to replace piston rings and valve stem seals. The turbocharger may also need to be checked for oil leaks.

💡 Prevention: Use high-quality synthetic oil of the correct viscosity and change it regularly. Avoid prolonged high-RPM driving and ensure the PCV system is working correctly. It is also good practice to check oil levels weekly.

🛠️ What Happens: A grinding or knocking noise is heard from the bottom end of the engine. The engine may have excessive end float and can suffer catastrophic failure. Often linked to clutch engagement on manual cars.

⚠️ Root Cause: The crankshaft thrust bearings, which control the fore/aft movement of the crankshaft, can wear prematurely. This is often attributed to poor lubrication, but can also be caused by heavy clutches or improper clutch engagement habits. The high thrust forces can eventually cause the bearings to fail.

🔧 Immediate Fix: A full engine rebuild is required, including the replacement of the crankshaft thrust bearings. In some cases, the crankshaft itself may be damaged and need to be replaced or re-machined.

💡 Prevention: Use a high-quality synthetic oil and change it frequently. Avoid holding the clutch pedal down for extended periods, especially on manual transmission cars. This reduces the constant pressure on the thrust bearing.

🛠️ What Happens: The engine misfires, idles roughly, or experiences a loss of power under load. An engine management light may flash or stay on, with codes like P0300 (Random Misfire) or P0301-P0304 (Cylinder-specific Misfire).

⚠️ Root Cause: Spark plugs wear out over time, leading to a weak spark. The coil packs, which deliver high voltage to the plugs, can also fail due to heat, age, or a failing spark plug putting extra stress on the coil.

🔧 Immediate Fix: Replace the faulty coil pack(s) and spark plugs. It is highly recommended to replace all four spark plugs at the same time and inspect the coil packs for any signs of cracking or heat damage.

💡 Prevention: Adhere to the manufacturer’s service intervals for spark plug replacement (typically 30,000 miles or less on a tuned engine). Use high-quality OEM or equivalent spark plugs and check them for signs of wear during routine maintenance.

🛠️ What Happens: The "AYC" or "ACD" warning light illuminates on the dashboard, and the Active Yaw Control (AYC) or Active Centre Differential (ACD) system becomes inoperative, leading to a loss of traction control and differential function.

⚠️ Root Cause: The hydraulic pump unit, which operates the AYC/ACD system, is located in a vulnerable position near the rear wheel arch and is prone to corrosion from road salt and water. The internal pump motor can also fail over time due to wear or electrical issues.

🔧 Immediate Fix: The pump unit may need to be rebuilt, or in severe cases, replaced entirely. A professional diagnosis is required to determine if the issue is mechanical or electrical. The system must be bled and calibrated with a specialised diagnostic tool.

💡 Prevention: Regular cleaning of the pump unit and surrounding area, especially in winter. Applying a rust-inhibiting coating can help to protect the unit from corrosion and extend its life. Ensure the AYC fluid is changed regularly as per the service schedule.