Hi,
My 1999 Land Rover Discovery 1, just threw a check engine light. I plugged in to get a code and code P0121 came up. The Disco has been idling a bit high and the other day it had trouble starting. I just had to give it a little gas pedal action and it started right up. I believe my throttle position sensor is sticking and is bad, so I went ahead and ordered a new one. While I wait for it to arrive, I figured I would just reach out on here to see if anyone has had this issue before.

Thanks,

 

Mine is doing the opposite, idling very low and won't stay running until it's almost up to temp. I replaced the idle air control valve and it helped a little bit but still not perfect. I'm going to follow this thread and see if I can't learn anything about mine too.

 

I just had a TPS failure on my D1 a few weeks ago. For awhile it would have a high idle that could be fixed by resetting the adaptive values, then that stopped working, then it started causing fuel cuts when letting off the throttle, then it finally gave the p0121 code. I swapped in a cheap one from Rock Auto and it was an instant improvement. She idles and cruises like a dream now.