Barry

I disagree with the whole German cars being reliable thing. Maybe 25-30 years ago, they got a reputation for being reliable and deservedly so but these days, not so much. The Volkswagen/Audi FSI/TSI are crap in terms of reliability for want of a better word, the DSGs are terrible for clutch and mechatronic system failures and horrendously expensive to repair when they go wrong. The Germans put so much focus on trying to cram their cars with new technology and gadgets that some of it is bound to fail at some stage. But to answer your original question, American or German? Japanese every time.

As said, signs of wear and tear generally point to high miles. Worn pedal rubbers, gearstick, steering wheel, drivers seat bolster. On a car with old style analogue odometer, make sure the numbers are all in a straight line, if one or more are slightly out of line, there is a chance it has been tampered with. Also check the screws on the dashboard above the steering wheel for marks caused by screwdrivers/torx or other tools. Also a good sign that someone has been in there tampering. On cars with digital odometer it's a bit more difficult to tell for sure without plugging it into a computer. Some cars log the correct mileage in the ECU whilst the display can show something completely different but the ECU will always have the correct miles. It's so easy to change the mileage on digital odometers too, all you need is a laptop, a lead and a piece of torrented software and you can change the mileage on many cars in a few minutes. On a side note, I once worked on a car in the UK and had to remove the dash clocks to fit a bulb and found a note stuck to the back saying 'Third time clocked LOL'. Some people have no shame.

Check that one of the balancing weights hasn't fallen off your wheel.

Why would you spend extra money changing 3 sensors when only one is possibly faulty? That's a very main dealerish attitude towards repair. The correct procedure would be to scan the fault code memory and see what it says. If a sensor has an intermittent fault, there will be a code logged towards it. If no codes are logged, the vehicle should be driven whilst plugged into the diagnostic tool and live data monitored and recorded so you can see exactly what's going on when the fault occurs. Even this doesn't mean a sensor is faulty. The wiring must be thoroughly inspected along the complete length from the transmission to the ECU. I have seen similar faults occur where 'mechanics' change and change various sensors but the fault still exists when the real issue was damaged sheathing causing the wires to the sensor to short circuit and send the vehicle into limp mode which was reset by turning the vehicle on and off again.