Could be wear on gear linkage , may need replacing .Here is an example
https://www.ebay.co.uk/itm/226073661008?chn=ps&_ul=GB&norover=1&mkevt=1&mkrid=710-166974-033325-9&mkcid=2&mkscid=101&itemid=226073661008&targetid=2276391439863&device=c&mktype=pla&googleloc=9046931&poi=&campaignid=21069693970&mkgroupid=165332018528&rlsatarget=pla-2276391439863&abcId=9387975&merchantid=114897452&gad_source=1&gclid=EAIaIQobChMIqM_Zv-OzhgMVxZxQBh3qiQFGEAQYByABEgLChfD_BwE
Posted May 29, 2024 (1 year ago)