This is likely a very simple problem to repair, and has been mentioned previously, the low light never comes on because the right side saddle still has fuel in it. Your problem will be in one of a few places;
- Faulty, or clogged fuel tank return tube/sub pump (There is a filter on the end of this tube that can get clogged)
- The fuel hose between the return tube and the pump assembly (clogged, disconnected?)
- Issue in the main pump (loose connection, failed part)
I would start with replacing the sub pump & filter, then while in there be sure the fuel hose isn't clogged or disconnected.
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2020 GMC Canyon Denali Duramax, 2021 Forester Sport, 2000 Subaru Legacy B4 RSK 5MT (JDM Import) and random 86 chassis rebuilds....