Recently, past day or two I notice when I make a stop, I hear water trapped under my car. As I drive it today I noticed a quick jerk when drive at a decent speed (30-45mph) or when I wanted to accelerate. I got back in my car and noticed the jerk became turned into a bad shake. I opened the bottom portion on the front passenger seat and water came out it. I had to drive in the shaking condition under 20 mph for a quarter mile to reach my house. Could this be a radiator or more severe issue ?
The water on the floor in the passenger side of the car suggests that you may have a leaking heater core. The [heater core]((https://www.yourmechanic.com/services/heater-is-not-working-inspection) is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant to heat the inside of the car with the help of the blower motor that blows the warm air through the vents inside the car. Due to the location of the heater core (behind the firewall/dash on the passenger side of most vehicles), it is common for a leak here to end up leaking coolant to the floor of the passenger side of the car. I would suggest having an expert from YourMechanic come to your location to diagnose your heating system.
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