300E Won't Start
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Newbie
Joined: Apr 2005
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300E Won't Start
I've read all I can find but still can't find the answer. My 300E has fuel and good spark but won't run...is the OVP still suspect. Here is the problem:
Vehicle wont start. 1992 300E 180K Check engine light on for past 50K. Car is a dailey runner about 50-100 per day no problems...Car sat overnight, would not start in AM (mild temp), tinkered around in the engine compartment, pulled air cleaner, nothing much. 30 minutes later car started fine. I kept it running and drove home (40 minutes) no problems. I shut it off and restarted in my garage 2 times with no problems. Came out 1 hour later, it started but ran as if it were missing a cylinder, turned it off. Later that day, tried to restart...nothing. It turns over but no go. I replaced plug wires cap and rotor. Great spark to plugs witnessed. Removed fuel lead to 2 jets at motor, lots of fuel available to engine. I can't figure why it won't start. Good spark with good fuel suppply but no fire. Ignition Control Module? Can you think of anything I can try myself?
Vehicle wont start. 1992 300E 180K Check engine light on for past 50K. Car is a dailey runner about 50-100 per day no problems...Car sat overnight, would not start in AM (mild temp), tinkered around in the engine compartment, pulled air cleaner, nothing much. 30 minutes later car started fine. I kept it running and drove home (40 minutes) no problems. I shut it off and restarted in my garage 2 times with no problems. Came out 1 hour later, it started but ran as if it were missing a cylinder, turned it off. Later that day, tried to restart...nothing. It turns over but no go. I replaced plug wires cap and rotor. Great spark to plugs witnessed. Removed fuel lead to 2 jets at motor, lots of fuel available to engine. I can't figure why it won't start. Good spark with good fuel suppply but no fire. Ignition Control Module? Can you think of anything I can try myself?
Newbie
Joined: Jun 2009
Posts: 1
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MB 300E W124
May the engine has too much fuel ,open the air fillter lid and then press the air flow sensor disk until full open and turn the throtle valve to max open and use the flash light to see the bottom of the inlet manifold ,if it flood with fuel , may be engine got some leak in any injector. You can get easier engine start by start with full throttle . 
Senior Member
Joined: Apr 2008
Posts: 405
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From: Forethill, Ca Northcal
85 euro w124 300d non turbo black on black......coming soon hx35 turbo intercooler
(while cold and wont start) Open flap with ur finger and spray starter fluid in it. Start car while pressing on gas peddle (might take a few sprays) when starts rev engine let go of gas pedal. if it dies Then spray starter fluid and repeat steps. When car starts rev engine until it warms up(dont let go of gas) It will take awhile. when warm let foot off gas if it idle that means ur idle valve is not working replace it. while idling kick on ur ac ur elect fan should turn on. If it doesnt then replace ur temp sensor.
Also I would get a new ovp relay anyways
Ovp relay controls idle and starts
temp sensor controls idle to computer
cold start valve controls ur starts
I had same symptoms and replaced all these
30 for ovp
idle valve and cold start got at junk yard
30 for temp sensor
Also I would get a new ovp relay anyways
Ovp relay controls idle and starts
temp sensor controls idle to computer
cold start valve controls ur starts
I had same symptoms and replaced all these
30 for ovp
idle valve and cold start got at junk yard
30 for temp sensor
