it was the accelerator cable - it is fine now. thanks for all the responses

yes - I have had many cars, although the last few have all had electronic engine management systems so the accelerator pedal does not have a cable as such. The spring looks to be the right one and I agree with discomania about the force needed to move the injector pump lever - mine is similar...

Hi, Just bought a 1994 Disco 300 TDI. I have never driven one before so have nothing to compare to but the accelerator pedal needs a lot of force to push down. I disconnected it from the injector? assembly and the cable itself was not stiff or sticking. The problem seems to be a strong spring...