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  #1  
Old 01-21-2014, 10:11 AM
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Duty cycle goes from 50% to 1.4% constant ...Help

560 SL
I purchased a used Fuel Distributor from EBAY,installed it,pressed the air plate before connecting the injector lines and fuel flows from the ports .
Connected all injector lines and started the car. It started OK with a some shaking and keeping about 750 rpms.And it was responsive when accelerator applied, it would rev nicely.

As soon as it reached the normal working temperature ,I pressed on the gas again and it bogs down and it dies.If I press it very slowly eventually it would rev but with trouble.

What is happening here? Any suggestions?
Is the FD bad ?



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Old 01-22-2014, 08:45 AM
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Any ideas?
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Old 01-22-2014, 11:44 AM
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Too rich mixture, I think.
I think, checking fuel volume to each cylinder & fuel pressures (system and lower chamber pressure) will be help on the first step.


Did you buy distributor with EHA as a whole kit?


Last edited by Dr. Sternschnuppe; 01-22-2014 at 02:27 PM.
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Old 01-22-2014, 10:11 PM
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The fuel pressure is in specs - upper and lower chamber.
The EHA came with the FD but was leaking and I replaced it with a new one.
The new EHA should come with factory settings, right.

It will run if you feather the gas pedal but if you step on it suddenly, the car
would bog down for 1-2 sec and then accelerate as it should.


Could it be a major vacuum leak that causes the rich mixture?
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Old 01-23-2014, 01:57 AM
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Quote:
Originally Posted by ioang26 View Post
Could it be a major vacuum leak that causes the rich mixture?
Yep.
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Old 01-23-2014, 09:11 AM
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Lower part of the air intake- round seals and gaskets?
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Old 01-23-2014, 12:05 PM
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Hm, I have reflected about it at leisure....
Vacuum leaks => more air => poor mixture. Isn't it?

Could you checking the fuel quantity to each cylinder per minute?
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Old 01-23-2014, 12:11 PM
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Question

Quote:
Originally Posted by ioang26 View Post
The fuel pressure is in specs - upper and lower chamber.
The EHA came with the FD but was leaking and I replaced it with a new one.
The new EHA should come with factory settings, right.
And with new EHA (factory settings) the differential pressure still is 0.4 bar (0.5 on cold [+20*C] engine)?
System pressure is 6.2 - 6.4?
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Old 01-23-2014, 12:21 PM
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And did you have checked or replaced the coolant temp. sensor?
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Old 01-23-2014, 12:45 PM
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The new EHA keeps the 0.4 bar differential pressure ,system pressure 6.3 bar.
I have not checked the temp sensor or replaced .
How do I check the quantity fuel per cylinder per min?
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  #11  
Old 02-17-2016, 01:14 PM
gmp gmp is offline
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I have the exact same isssue(Duty cycle goes from 50% to 1.4% constant), I'm going through much of the same CIS restoration you did due to my 89' 560sl having sat for a few years prior to me purchasing it.

Any info on how you resolved this issue would be a huge help!

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