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**bayhas** · 04-19-2008, 05:41 PM

you have 3 separate problems.

rough idle with hissing sound: you have major vaccum leak, follow the sound and you ll find the broken/deattached vaccum line

oil pressure: check oil level and viscosity, mercedes manual does not want you alarmed if the the oil pressure is 0 at idle, as long as the red light is not on, and the needle goes up in pressure as soon as you rev up. do an oil change anyway and see what happens.
if the pressure does not go up when you hit the gas, DO NOT DRIVE THE CAR AND TURN IT OFF RIGHT AWAY

hard to push gas pedal: from what you are describing, the car is in the limp home mode
if the car is idling, and you hit the gas, does the pedal travel 1/2 way to the floor before the rev goes up?

04-19-2008, 05:41 PM	#4 (permalink)
bayhas Premium Member Date registered: Oct 2005 Vehicle: 300SE 3.2L DOHC, 190E 2.3L SOHC, Saturn SCX 1.9L DOHC. Location: Framingham / Boston - MA Posts: 2,918	you have 3 separate problems. rough idle with hissing sound: you have major vaccum leak, follow the sound and you ll find the broken/deattached vaccum line oil pressure: check oil level and viscosity, mercedes manual does not want you alarmed if the the oil pressure is 0 at idle, as long as the red light is not on, and the needle goes up in pressure as soon as you rev up. do an oil change anyway and see what happens. if the pressure does not go up when you hit the gas, DO NOT DRIVE THE CAR AND TURN IT OFF RIGHT AWAY hard to push gas pedal: from what you are describing, the car is in the limp home mode if the car is idling, and you hit the gas, does the pedal travel 1/2 way to the floor before the rev goes up? __________________ Mercedes-Benz, W140 S class 300SE Mercedes-Benz, W201 190E 2.3 Stock 1996 Saturn SC1 + 95 DOHC head + 96 camcover + 98 Vsprings + 02 block + 00 crank + 91 header + 01 MP2 = SCX - Soon to be turbocharged.