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Showing matches for "oil leak".
When Is an Oil Leak Actually Serious?
Not every oil leak is a disaster, but location, smell, belt contact, and repair access decide the real risk.
BMW B48 Ownership Signals: What to Inspect Before Buying
A practical B48 inspection covering cooling stability, oil leaks, ignition quality, boost behavior, service history, and diagnostic evidence.
PCV Failure on Turbo Petrol Engines: Small Part, Big Symptoms
How crankcase ventilation failures create oil consumption, boost leaks, rough idle, smoke, and misleading diagnosis on modern turbo petrol engines.
Misfire Diagnosis: Coils, Plugs, Injectors, or Compression?
A structured way to think about misfires on German cars, from ignition basics to fuel delivery, air leaks, and mechanical compression faults.
BMW B48
Modern turbo-petrol four-cylinder that is usually a strong base when cooling, oil leaks, and service intervals are controlled.
MINI Brand Hub
MINI reliability, BMW-derived engines, cooling, oil leaks, timing, turbo, and used-car buying guidance.
Audi Oil Consumption Questions Before Buying
What to ask and inspect before buying an Audi where oil consumption history, engine generation, and service proof matter.
How Fuel Trims Reveal Vacuum Leaks Before You Buy
Fuel-trim behavior at idle and under load can expose PCV, purge, and intake leaks that a quick visual inspection misses on a used petrol car.
P0093: Large fuel-system leak detected
Fuel pressure is dropping at a rate that the ECU interprets as a major leak or excessive internal loss.
P0442: EVAP system small leak detected
The fuel-vapor system cannot hold the small vacuum or pressure change expected during the leak test.
P0455: EVAP system gross leak detected
The fuel-vapor system has a large leak or cannot seal during its self-test.
P0456: EVAP system very small leak detected
The fuel-vapor system has a very small leak during the ECU's leak test.
VAG EA888
A broad turbo-petrol engine family whose risk changes significantly by generation, oil behavior, timing design, and cooling history.
P2279: Intake air system leak
The ECU detects extra unmetered air entering the intake system.
2019 Volkswagen Arteon Reliability and Buying Guide
2019 Volkswagen Arteon reliability, TDI/TSI engines, DSG service, 4Motion/Haldex checks, electronics, and ownership planning.
2020 BMW 4 Series Reliability and Buying Guide
A model-year view of the late BMW 4 Series, including B48/B47 choices, ZF gearbox checks, coupe body condition, and ownership risk.
2021 BMW X1 Reliability and Buying Guide
2021 BMW X1 reliability, B47/B48 engine checks, xDrive tire sensitivity, gearbox behavior, and compact SUV inspection advice.
BMW Brand Hub
BMW reliability analysis, common problems, buying guides, and engineering-driven maintenance insights.
P0301: Cylinder 1 misfire detected
The ECU detected repeated combustion misfires on cylinder 1.
P0302: Cylinder 2 misfire detected
The ECU detected repeated combustion misfires on cylinder 2.
P0305: Cylinder 5 misfire detected
The ECU detects repeated combustion failure specifically on cylinder 5.
Why Cooling System Plastics Matter on German Cars
Cooling system plastics, heat cycling, leaks, and why small coolant problems can become large ownership costs.
P2187: System too lean at idle, bank 1
The ECU detects a lean condition mainly at idle, where small air leaks have a larger effect on mixture control.
BMW B47 DPF and EGR Buying Signals
How to inspect a used BMW B47 diesel for DPF loading, EGR history, cooling faults, short-trip use, and weak diagnostic evidence.
DPF Regeneration vs Blockage: Read the Evidence Before Replacing Parts
Understand soot load, ash load, differential pressure, exhaust temperature, driving pattern, and why forced regeneration is not a universal repair.
EA888 Timing Chain Risk: What Buyers Should Understand
A clear engineering explanation of EA888 timing chain risk, symptoms, inspection clues, and why service history matters.
EA888 Water Pump and Thermostat Module: Cooling Clues Before You Buy
Coolant residue, unstable temperature, pump faults, and repeated top-ups can reveal EA888 cooling-module problems before purchase.
2018 Audi A4 Reliability and Buying Guide
2018 Audi A4 B9 reliability, EA888 and TDI checks, S tronic behavior, cooling risks, and pre-purchase priorities.
2020 Audi A4 Reliability and Buying Guide
2020 facelift Audi A4 reliability, engine and S tronic choices, digital systems, cooling checks, and ownership planning.
Audi Brand Hub
Audi reliability analysis, common problems, TDI/TSI guidance, and engineering-driven buying insights.
BMW B47
A more mature BMW four-cylinder diesel with improved timing architecture but continued emissions and service sensitivity.
C1130: Chassis control or suspension pressure fault
A chassis or suspension control module has detected an implausible pressure, height, or control-state condition.
Mercedes-Benz OM651
Widely used diesel with strong fundamentals but meaningful injector, timing, cooling, and emissions-system dependencies.
P0011: Intake camshaft timing over-advanced, bank 1
The intake camshaft is more advanced than the ECU expects for the current operating condition.
P0014: Exhaust camshaft timing over-advanced, bank 1
The exhaust camshaft position is more advanced than commanded or is slow to return to the expected position.
P0016: Crankshaft / camshaft timing correlation
The ECU sees the crankshaft and camshaft signals outside their expected relationship.