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The throttle assembly is expensive as the part is costly. The labor to replace it is about 1-1.5 hours and maybe another 1.0 to replace the throttle wiring connector pins. That price quote is average for that repair. Just make sure this is a new throttle from Jag. Sorry for the bad news.
does that fix seem to make sense? is it possible that loose connector pins or battery issues could be the problem. the codes that were produced were p1632 and b1121. the first seems to be related to voltage. also the gear box fault light wasn't on when he checked. and as I said it can go weeks without a problem. haven't been on the lookout but it seems first time it happened we had a lot of rain. after a day or two it worked fine. seems like one other time it happened it was after a lot of humidity and wet weather. I have read a lot on line about some of the connectors getting wet and causing some of those kinds of codes. if throttle body really is the issue How would I know? if it is a part that brakes then it should stay broken not work intermittently? at least that is what I would think but you are the expert let me know.