When your driving the car and the check engine goses on. Then when you start it up agin it gose off.

First thing i would do is give it a complete tune up, to include plugs,cap, rotor, wires,fuel filter,air filter and fuel system cleaner. Good luck

some cases . if engine lose vacum need more gasoline inside to start and reach the too mach air gose inside in this case you have to check all hoses from intake manufold (maybe crack or loose or remove out , one line gose to brake difram this have valve (one direction valve ) this one effect direct to brake (hard to press). the anther case maybe disconnect idle nosil socket or loose .check wire lom gose to throtell valve .

thermostate housing?

possibly faulty electronic fan control module which is inside the radiator fan, must get your car in to the Mercedes workshop and read fault code and also they can activate and check is the fan is working or not by there diagnostic CPU, if the activation dos not work, then replace the radiator fan , is this information helped you?

hi this sounds like your pump is going, have you checked the fluid in the reservoir? make sure its is up to the end of the dipstick and is not dirty as it could need new fluid in it, also check for leaks on the pump, either look under where the motor is and locate the pump, check to see if there are any drips of pink fluid leaking this could cause air to get into the system and make the steering do what you are having problems with,you can also get a large section of cardboard put under the motor area and then start the engine wait for 10 minuets and see how much is lost if any...hope this helps

Check the fuel lines under the car. Don't actually start the car though, just turn the key until you hear the fuel pump turn on. This will load the fuel system and you will be able to see leaks (or sprays) under the car because of the pressure. If there are no leaks, see if the car runs perfect with a full tank of gas compared to a low tank. It should drive good turning left, but it might **** turning right or after a sudden stop. This could mean you have a crack in the seams of your gas tank or that your fuel pump is going bad (or a little of both).

If the engine isn´t making any abnormal mechanical noises, then I would expect the oil pressure sending unit at fault.
If however the engine does make more or abnormal mechanical noises, it could be a too low oil pressure and this should be addressed immediately.

Use thinner oil in the winter. A synthetic would be best, like 5-30.

WELL WHAT YERA IS THIS TRUCK AND IS THE SOUND COMING FROM FRONT OR IS COMING DOWN DRIVE LINE IT COULD BE AT TRANSFER CASE THAT WHY IT GOSE AWAY WHEN IN FOUR WHEEL YOU COULD PULL THE DRIVE LINE IN FRONT AND SEE IF NOIS GOSE AWAY THEN ITS IN FRONT IF ITS THERE WITH DRIVE LINE OUT PUT IN GEAR AND IF NOIS GOSE AWAY THEN ITS THE TRANSFER CASE

if its at the top end its pistion slap
if its at the bottem end(of your engine) its a crank shaft bearing.

with out going into extream detail,

a ting sound at the top is a pistion slap.... replace all your pistions posibly over hual the engine.

a dubble knock that gose with rpm but sounds 2 knocks very every fireing of the pistion is a crank bearing..... replace your crank shaft bearings.... all of them b/c metal gose threw an engine extreamly fast and will destroy other beraings. this knock on start up will turn into a knock all the time, then a very louad knock that will end your engines life.

unfortunetly the answer is engine rebuild and fast.