94 E320 Engine and RPM revving in idle?
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MB '94 E320 (W124)
94 E320 Engine and RPM revving in idle?
Hello, I have a '94 E320 and just last night something odd started happening. Let me first start off saying that I don't know jack about cars. When I turn on the car, and don't start the engine, everything is fine and normal. When I start the engine, the car begins revving every 2 seconds or so, and the rpm goes with it. This is without moving. When I move it a bit, the gas only pushes the car when I press it down further than I normally do, and even then it feels like the electronics keep turning on and off and the rpm keeps revving, feeling very unstable to say the least. Right when I turn it on the SRS light is on but it quickly turns off. Some of the other notification lights on the dashboard also flash when the car is revving.
Does anyone have any idea what might be going on? I have rudimentary mechanical knowledge so if this sounds like it can be simply fixed by cleaning out some sort of hose or something I'd be willing to try that first.
Thanks for your time.
Does anyone have any idea what might be going on? I have rudimentary mechanical knowledge so if this sounds like it can be simply fixed by cleaning out some sort of hose or something I'd be willing to try that first.
Thanks for your time.
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Joined: Aug 2007
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From: USR, NJ, United States of Americaland
1994 C124 E320 Coupe - 1975 W116 280S
That's called idle surging.
Most likely a vacuum leak cuz the engine idle is dependent on vacuum. Also could be MAF (Mass-airflow) sensor or AFM sensor (Air flow meter) or a bad idle control valve.
Most likely a vacuum leak cuz the engine idle is dependent on vacuum. Also could be MAF (Mass-airflow) sensor or AFM sensor (Air flow meter) or a bad idle control valve.
