Radiator recent changed

this vehicle is showing the following codes during an inspection what are they, how to fix and how much to fix
po650 mil contrlol circuit malfunction
p2272 025 signal lean
po157 025 low voltage
p0057 cicuit low

Gas level fluctuates

This happens all the time when I put in gas the car has a tough time starting once i get it started I need to rev it up for about 30 seconds then slowly take foot off the gas but keep reeving at about 1000 rpm foot on brake then put in drive once it gets going the problem goes away until next trip to get gas, any help is appreciated. Thanks

My mechanic told me my engine is full of water. My oil dipstick did not show any signs of water being in the engine. How else can it be diagnosed as full of water?

I had my Hyundai towed to the dealership today bc when I started it this morning the engine light was on and it was making a loud knocking sound. I have a warranty on this vehicle up to 125000 miles. It has about 108000 miles on it. When the mechanic called me to tell me what caused it he said that my engine was full of water and it would not be covered in my warranty. There has been massive flooding here the past few days and I feel like he is just saying that bc he's been diagnosing flooded cars all day. I am just afraid of getting ripped off and want to know how a mechanic would know if there was a flooding issue. Yes, I did go through water but nothing even close to my hood being submerged. Thanks so much for any and all advice or suggestions.

but there is no electronic connections to ps system. No fluid loss, inconsistently happens, always 2 seconds or less, usually at low speed like a parking lot or turning a corner, car is warmed up, weather is sunny and warm. Has happened 3 times in 6 months. No check engine light.

put to much gas in tank and mess up purge valve

Fuel pump has already been replaced

engine noise on startup