The station run is harder on a turbo than a motorway trip
A very common Morden pattern is a mile or two to the Underground terminus, a day parked, then a mile or two home. London Road through the town centre is dominated by buses, bus stands and crossings, so even that short trip is mostly stationary. Merton's controlled parking zones M1 to M4 discourage all-day parking, which pushes more of that short-hop driving onto residents. A diesel on this diet never gets its exhaust hot, and the variable geometry vanes slowly bind with soot and oil mist.
The St Helier estate's long residential avenues with traffic calming and parked cars do the same thing, and so does Bishopsford Road through to Imperial Fields. The one stretch where the car finally gets asked for real boost is St Helier Avenue, where the limit is now 30mph and traffic runs steadily to the Rose Hill roundabout. That is where people notice the flat spot or the limp mode, even though the cause has been building for months at low speed.
Before we talk about a replacement turbo we check the three things that imitate one. A smoke test finds split boost hoses and cracked elbows. Actuator travel and the boost sensor reading show whether the control side is at fault rather than the turbo. Exhaust back pressure tells us whether a particulate filter clogged by the same short journeys is choking the engine. Only then do we measure radial and axial shaft play against the manufacturer's limit for your unit.
If the turbo is genuinely worn we ask why before fitting another. Oil condition and level, the feed and drain lines, the crankcase breather and the air filter housing all get looked at, because a restricted feed will destroy a new unit at the same mileage as the old one. You get a written quote with a new and a remanufactured option, fresh oil and filters included, collection and delivery available, and a 3-month workmanship warranty.