Heater valve How long should it take to install heater valve in 2000 Jag S type.

THEIR IS A VALVE ON THE RIGHT SIDT OF THE VECHILE HEATER VALVE RIGHT AT THE FRONT JUST BEHINED THE BUMPER THAT NEEDS CHANGIND OR CHECK THE CONNECTIOS TO IT FIRST.

Replace your heater control valve, its the device that channels hot water either around your engine only or when the valve opens it channels it through your cabin also..
They are quite common to fail on pre02 cars...
if all your electrics are ok, and the car is running normal temps, try feeling the pipes around the valve.. its located behind radiator left side looking down.. could even check all related fuses, just to be sure..
Good luck

Probably the heater control valve, had same issue, started with one side not hot, then erratic, hot then cold while heat is set to hot, now both side are cold to lukewarm. diagnosed as heater control valve, common for jag s-types and x-types. located on the passenger side, down low the side of the radiator, it has several hoses into and out of valve, and a electrical connector.

how do i disconnect the wires on a heater control valve on a s-type jaguar with a 3.0 engine.

Without additional information, it sounds like the new heater valve is not connected electronically. Without voltage the valve will default into an open position, causing the heat to stay on. check electrical connection to valve, simply press on top of connector to ensure tight fit. if ok, check fuse.
Once its connected properly the valves will close automatically and will only allow hot water to flow to heater core when driver turns it on from climate control switch.

Sounds like its the blend door actuator has failed or loose or cracked vacuum line going to it. These are usually not fun to replace although I dont know about your specific model, but most that I have seen you have to remove the dash.

if i use regular gas for s type jag 2004 will it hurt car

my heater only blows cold air please could you give me some advice on this thanks . everything else is ok temp ,engine etc

Its likely to be the heater contol distributor located in the front of the engine compartment under the right hand (when sitting in the drivers seat) headlights. Its very difficult to get to, it took me around 2 hours to change. Its ideally done on a ramp & cost around £150 (ukp) for the distributor valve block + £30 for proper antifreeze aprox 2 years ago.

You have 2 zone temperature control control. The heater control valve has failed and is open allowing the passenger side heater core to stay hot.
It is a very common problem and expensive to repair. It tends to be an intermittent problem and sometimes will work properly.