300sl hard to start - Mercedes-Benz Forum
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post #1 of 4 (permalink) Old 07-08-2009, 02:36 PM Thread Starter
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300sl hard to start

newly purchased 1991 300SL with 6 cyclinder, 5 speed is very hard to start for the first time in the morning- not cold weather. Once it warms up, all is ok. But getting it to go the first time really takes alot of cranking. What could be the problem? thanks for your help. Andy

Last edited by ahats; 07-08-2009 at 02:36 PM. Reason: left our info
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post #2 of 4 (permalink) Old 07-08-2009, 03:31 PM
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Welcome to BenzWorld! I'll slide your query down to the R129 section, where you're far more likely to garner a helpful response. You might also consider completing your user profile, many find that information helpful in regard to providing you with the best possible response.

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post #3 of 4 (permalink) Old 07-09-2009, 01:05 AM
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Hi ahats and welcome aboard in our big friendly international family. Please remember to update your profile with your car year and location to hlep us help you in the best and quickest possible way.
You might want to get familiar with the advanced search feature of the forum and with the third blue sticky that's a "R129 all you have to know" guide.
Unfortunately I dont' have an answer for your problem but in a mattter of hours someone more knowledgeable than me will chime in with a possible solution.
Meanwhile how many miles has your car on the clock and how is your battery?

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post #4 of 4 (permalink) Old 07-09-2009, 06:55 AM
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Originally Posted by msbarsi View Post
Meanwhile how many miles has your car on the clock and how is your battery?
Yes, and how much did you pay for your car? I have a 300SL 5-speeder that I might put on eBay, and I would like to have an idea what it might sell for.

Your cold-start problem may be due to a faulty coolant temperature sensor, a faulty Electro-Hydraulic Actuator (EHA) on the fuel distributor, or a faulty Overvoltage Protection Relay (OVP). I would begin by reading codes for the fuel injection and the ignition as explained here: https://www.benzworld.org/forums/r129...pre-94-a.html? If that gets you nowhere, then I would measure: (1) the resistance of the temperature sensor when cold, and (2) the current to the EHA. If you reach that point and need more help you can reply back.
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