Hi everyone
my car drives me crazy , i have a 1991 Mercedes 190D 2.5 that runs hotter than normal and that causing oil pressure to drop to 1 bar in all time even it get worse on hills or when ac on
i inspected every thing even i just replaced the thermostat but nothing changed
both fans are working ,i flushed the engine and the radiator with hydrochloric acid
no play in water pump and no cracks on hoses

but there is some symptomes that i think are goin to help :

the heater isnt hot enough
and the lower radiator hose is colder than the uper one
and yes i know this is the symptome of a worn thermostat
but i juste replaced it with a new one
thats crazy
we were fine with horses why they invested cars
horses are simple and cheap to maintain

thanks alot my friends and sorry for my bad english