Repair Make-Model-Year Filters

My Shopify store, https://autopartavenue.com/, uses a three-step Make → Model → Year selector that pulls its data from product metafields. Right now the cascade breaks: choices don’t narrow correctly and the “Find Parts” button sometimes returns incomplete or empty results, leaving the right-hand refinement menu out of sync.

I need the underlying Liquid and JavaScript repaired so that:

• each dropdown populates only the valid options that match the previous selection,
• clicking “Find Parts” immediately returns every relevant product, and
• the sidebar filter reflects the same item set with no lag or mismatch.

The metafield structure is already in place; your job is to trace where the logic fails, correct the Liquid/theme code, and confirm the solution across desktop and mobile. I am familiar with typical development timelines, but I will only pay the amount you bid—please factor that in before accepting. Prior hands-on Shopify Liquid experience is essential; if you haven’t done this work before, this project isn’t for you.

If your bid changes when we discuss the project you will not be given this project