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Unpredictable starting

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Old Dec 9, 2006 | 07:43 PM
  #1  
gartracescort's Avatar
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Joined: Nov 2006
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From: UK, midlands
S500L, 1995
Unpredictable starting

Always spins over fine, but won't always catch first or sometimes second time? Had a new engine loom and rebuilt throttle body. Runs perfect when it starts. No difference hot or cold, wet or dry.

Help please.
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Old Dec 11, 2006 | 01:39 PM
  #2  
Rod Spohn's Avatar
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From: Mesa, AZ
2011 E350 Bluetec, 1996 S320 & 2006 E320 CDI Sold to my son & 2017 GMC 2500 Diesel Pick up
Question

What do yuou mean just spins? Turns over but doesn't start or spin like the starter is not engaging?
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Old Dec 12, 2006 | 08:03 AM
  #3  
gartracescort's Avatar
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From: UK, midlands
S500L, 1995
starter motor engages and spins the engine, but engine does not run first time. This seems to be a spark issue.
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Old Dec 12, 2006 | 10:57 AM
  #4  
Rod Spohn's Avatar
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Joined: Apr 2004
Posts: 393
Likes: 2
From: Mesa, AZ
2011 E350 Bluetec, 1996 S320 & 2006 E320 CDI Sold to my son & 2017 GMC 2500 Diesel Pick up
Originally Posted by gartracescort
starter motor engages and spins the engine, but engine does not run first time. This seems to be a spark issue.
Well I hope this will help you not go through the hastle I did with this problem. The Machanic replaced a couple of sensors befor someone on this site jumped in with the answer. So I'll pass it along. Change out the fuel pressure regulator. ($98.21 @ Autohaus) Its very easy for you to do yourself. Its on the front right side , top by the fuel rail. ( front right looking at engine from front) The only way I was told you can check it before replasement is to pull the Vac line and smell/look for gas. Its a Vac line and shouldn't has gas in it - not even a drop. It was so easy I kick myself for not asking this forum first before spending probably $600 at the shop.
Good luck

Drive on
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