Filled up my civic at Valpark gas station last week Monday. Shortly after fulling up and driving on the highway, the tach started fluctuating. Tach would be at 6000 rpm then suddenly drop to 1000 rpm. It sounds and feels like the engine dies for a second. Scary as firetruck

The car also stalling and hard starting, sometimes.
Battery under warranty, was replaced.
Alternator checked.
Plug wires changed.
Full service done (Air filter, fuel filter, oil and oil filter change, etc)
Spark plugs checked.
Fuel pump engaging before i start the car normal.
No CEL.
Transmission checked.
ECU was reset.
Still getting hard starts, sputtering and fluctuating rpm but less frequently now.
I let the gas run down to a lil below 1/4 ..I added a bottle of Redline complete fuel system cleaner and filled up at Medford today.. (They're Unipet now so a lil safer, place looking new)
Next step is to drain the gas tank completely if it doesnt go away.
Anybody have any ideas?