There is a high pith noise when I press the accelerator pedal on Volvo S80

code p 0121 refers to throttle position (TP) sensor A/accelerator pedal position (APP) sensor A--range/ performance problem===causes ---accelerator cable adjustment--TP/APP sensor ---wiring

check power steering fluid level.

Hi theres a switch on the brake pedal & a solenoid on the gear shift to stop you moving whilst the car is put into drive if the switch is not working correctly it won't release the solinoid to release the gear shift or the soinoid is faulty or your not pressing the brake down hard enough hope this helps

the brake disks are worn and the pads getting low so with the wear on everything as you de accelerate the brake pad is now hitting the ridge built up edge of the disk

HI, the code is for the Throttle Position Sensor/Accelerator Pedal Position. See attached image.

I took the car to volvo garage in the morning . They found out that there was a cut cable in the engine compartment near the throttle valve.
Anyway i want to express my thanks to you for your immediate response.

Regards
George

when you are sitting idle and you press the clutch without putting it into gear does the noise go? if so you will need to fit a new clutch kit.

its a high mileage engine.
all you need to do is use a thicker oil and the light will go out at idle speeds.

use a 50w sae valvoline racing oil.
plus stp oil treatment.

do that and that light is all gone.

This is, without doubt, your Brake servo unit. The diaphram is leaking, hence the noise. You will have to get part number V30793673-2, Cost me €500 in Ireland. No repair available, and a bit difficult to install too....

Replace The Brake Booster.