Opel Corsa 1.7 DTI C

This is the most well-documented fault on the Y17DT engine. The EDU (Electronic Diesel Unit) controls the injection pump's spill valve, which draws very high current. Over time, this current overload destroys the driver circuit inside the EDU. Symptoms include intermittent engine cut-outs (especially when warm), failure to start, or the engine starting then immediately dying. Fault codes typically blame the spill valve, but the root cause is almost always the EDU itself. Specialist ECU rebuild services offer repairs for approximately €120-200 with a lifetime warranty. A used replacement EDU costs €50-100 but may fail again. A new unit from Opel (when available) runs €300-500 fitted. The repair is plug-and-play and does not require recoding. This issue can occur at any mileage and age, but most units fail between 100,000-200,000 km.

The Corsa C uses an electric power steering column with an internal torque sensor that can degrade over time. The steering typically becomes heavy in one direction first (usually left), progressing to complete loss of power assistance in both directions. Common fault codes are C1507 (motor voltage) and C1500/C1502 (torque sensor). Water ingress into the control box can also cause failure. A new EPS column from Opel costs approximately €800-900 fitted, but specialist rebuild services can repair the torque sensor or control unit for €150-250. Remanufactured columns are available for €200-350. This fault affects all Corsa C models regardless of engine type, typically appearing after 80,000 km or 8+ years.

The Y17DT uses a small Mitsubishi turbocharger (TD025) that is generally reliable but can develop bearing wear after 120,000-180,000 km, particularly if the engine was regularly shut off immediately after sustained load without a cool-down period. Symptoms include blue or white exhaust smoke, whistling or grinding noises, and progressive power loss. A new aftermarket turbo unit costs approximately €170-310, while a remanufactured unit runs €200-400. Including labor (3-4 hours), the total replacement cost is €400-1,200 depending on parts choice. Separate from the turbo itself, the boost solenoid can stick and the vacuum lines can split, cutting boost under load. These are inexpensive fixes (€30-90 for solenoid, vacuum hoses are pennies) but must be diagnosed correctly to avoid unnecessary turbo replacement.

The glow plug system on the Y17DT relies on a relay located behind the nearside headlamp. This relay can either stick on (overheating and eventually burning out the glow plugs) or fail to engage (causing difficult cold starts, excessive cranking, and white smoke). The high current drawn by glow plugs can also cause arcing at connector terminals, creating high-resistance joints. The relay itself costs approximately €20-40. Individual glow plugs are €10-20 each (four required). A set of glow plugs with relay replacement at a garage typically costs €100-250 all-in. The wiring should be inspected for corrosion and damaged insulation, particularly on cars that have spent winters in salt-road regions.

The EGR valve accumulates carbon and oil residue over time, particularly on cars used primarily for short urban journeys. Symptoms include rough idle, reduced power, increased exhaust smoke, and the engine warning light. The problem is very common on Y17DT engines after 80,000 km in urban use. Cleaning the valve can provide temporary relief (€50-100 at a garage), but replacement is often more practical. A new EGR valve costs approximately €60-150 for an aftermarket part, with 1-2 hours of labor. Regular longer drives at higher RPM help prevent carbon buildup. Some owners fit blanking plates (€20-30) combined with a remap, though this is not legal for road use in most EU countries and will fail emissions testing.

The 1.7 DTI uses a dual mass flywheel that can develop a rattle at idle, typically heard as a chattering noise that quietens when the clutch pedal is depressed. This is a gradual wear item rather than a sudden failure, but a worn DMF can damage the clutch and gearbox input bearing if ignored. A LUK or Sachs DMF costs approximately €200-250, a clutch kit (friction plate, pressure plate) runs €100-140, and a concentric slave cylinder is €40-50. Including labor (4-6 hours due to gearbox removal), total replacement cost is typically €500-800 at an independent garage. Most DMFs last 120,000-180,000 km under normal use.