Zz could themostat be sticking?

Before it stopped running it was losing power and idled up and down

Backfires and won't start

I have replaced the blower motor resistor. When vehicle is started ABS and BRAKE light come on and door chime sounds. No blower but I can hear the compressor for Ac come on. I can restart over and over and sometimes everything works fine.

I have checked the calipers, brakes, fuses and belt. Could this be electrical or maybe the alternator?

Towing a trailer about 6000 pounds at high way speeds

My van started fine this cold day with in 5 min engine cutting in and out during warm up gages, lights flashed before stalled. tried to start engine cranked over and fired. Sat a few hours tried again in nuteral and ran strong till back in park and stalled again. tried reset, took off battery connections Neg & Pos hoped to reset computer codes? Brand new Fuel pump, plugs, wires, module, fresh gas replaced round 65,000 after using diesel fuel. ran good till today has K&N Air filter installed. Cranks but not will start or run

I turned the key on and off several times but it wont crank over. Battery is good. Already replaced started and relays. If I turn the key on and off enough times it might start once. Gages are flickering.

smells like it is over heating,but temp is normal and loses water and anti freeze

Where is the oil sending unit?

I can't find a sink to pour out the coolant.