SL/R129: 1993 300 SL Electric or Fuel Problem
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Joined: Sep 2017
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1993 300 SL
1993 300 SL Electric or Fuel Problem
Hi,
Where can I find a good diagnosis procedure for a 129 with a 104 engine (300 SL)? I think I have a fuel delivery problem. The engine will only run on a prime, then stops. Tach does not register while it runs. Pole 14 (MAS) at the diagnostic connector has 0 flashes. Pole 3 (CIS) has one flash. Pole 8 (EZL) flashes 17. I've replaced the crankshaft position sensor, both fuel pumps and fuel filter. Seems the fault may be in the MAS or the EZL. I jumped the terminals at the MAS to verify that the pumps operate. Fuel, however, does not seem to reach the engine.
Any suggestions would be greatly appreciated.
Thanks,
Harry
Where can I find a good diagnosis procedure for a 129 with a 104 engine (300 SL)? I think I have a fuel delivery problem. The engine will only run on a prime, then stops. Tach does not register while it runs. Pole 14 (MAS) at the diagnostic connector has 0 flashes. Pole 3 (CIS) has one flash. Pole 8 (EZL) flashes 17. I've replaced the crankshaft position sensor, both fuel pumps and fuel filter. Seems the fault may be in the MAS or the EZL. I jumped the terminals at the MAS to verify that the pumps operate. Fuel, however, does not seem to reach the engine.
Any suggestions would be greatly appreciated.
Thanks,
Harry
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Joined: Jan 2006
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
I would try to start and rung the engine with all electronic control of the fuel pumps bypassed. You do that by removing the MAS and jumpering together its connector sockets #1 and #2.
Super Member
Joined: Jul 2010
Posts: 598
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From: Eastern Kansas
94 SL 600, 98 993, 89 XJS Conv., 85 Daimlier Princess 16 Hybrid Lincoln 16 Chevy crewcab
Harness status
While I turn these problems over to people with voltmeters not hammers, my first question for a 93-95 year range is what is the condition of the engine wiring harness?
