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Discussion Starter #1 (Edited)
This car has been a source of endless troubles. A few weeks ago, the car engine started stopping when the car came to a stop. Sometimes it would be a struggle where the rpms would try to sustain but fail, and other times just dies like I have turned the key to shut it off. After shutoff, the instrument cluster goes into its state of when I turn the key to position 2. I have noticed that sometimes, the red battery light comes on while the engine struggles and then dies. The car also sometimes hesistates when I apply the throttle. I have replaced the cps and maf. The engine runs well when it doesn't hesitate or stop. The car is able to restart immediately after. Could trying the throttle reset procedure help? Thanks.
 

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You may have a fuel delivery problem. Do a fuel pressure test , you may have to do it until the engine hesitates or dies. So you will have to leave the gauge hooked up and when it stalls see what the fuel pressure reads. You will have to zip tie it somewhere safe or as witek suggested rig it up to go up to the windshield so you can watch it while driving. Engine running it should be around 50-55psi. Engine off after 30 minutes it should sit around 36psi. Your battery light is probably only coming on because your ign is on and engine revs become very low just before stalling.


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Discussion Starter #3
You may have a fuel delivery problem. Do a fuel pressure test , you may have to do it until the engine hesitates or dies. So you will have to leave the gauge hooked up and when it stalls see what the fuel pressure reads. You will have to zip tie it somewhere safe or as witek suggested rig it up to go up to the windshield so you can watch it while driving. Engine running it should be around 50-55psi. Engine off after 30 minutes it should sit around 36psi. Your battery light is probably only coming on because your ign is on and engine revs become very low just before stalling.


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I may have forgotten a major key point which is that the car can start normally immediately after the shutdown. Does your theory still apply? Sorry :(
 

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Can you get the car scanned for codes. It might help us pin point the problem a little easier.


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Discussion Starter #5
Can you get the car scanned for codes. It might help us pin point the problem a little easier.


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I have scanned with a obd 2 with no codes coming up. Do you mean to use something like the Star system to do this? There is also no cel.
 

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I would still follow Matt's plan to check the fuel pressure.
No pressure or dropping pressure will not throw a code that a regular ODBII scan tool will read and rarely a code the MB Star can read.
 

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I have scanned with a obd 2 with no codes coming up. Do you mean to use something like the Star system to do this? There is also no cel.


Without any codes it's a start that won't cost much. Getting it scanned with a pro level scanner if the fuel pressure checks out would be money well spent. Money better spent would be getting a decent scanner if you plan on keeping the car. They pay for themselves very quickly.


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Discussion Starter #8
I have looked into getting the equipment needed to get the pressure of the fuel line. Another thing has happened to the Ml320. The car has now consistently refused to hold idle. Even with the pedal to the floor, it runs like a pig and is shuddering like crazy. Could this be confirmation that the fuel supply has gone bad? Still have not thrown a cel.
 

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Starting to sound like it. We are only guessing without a bit of proper diagnosis though. Let us know how the fuel pressure test goes.


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Discussion Starter #11
Hello, sorry for the giant hiatus on replying to this thread. The pressure tester came in and the fuel system held pressure fine. The current symptoms now is no CEL (I have checked if it's iluminated at pos. 2), and the car dies 2 or 3 seconds after I start it. Now it dies like it's being shutoff with no struggle at all. Starts are strong and completely normal and the car will rev up to however high it can reach before I lose control of the engine with my throttle and the revs drop down to 0.
 

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Are you saying the CEL is not on in position 2 or it is on in position 2. Important since if it's not on in position 2 the bulb is probably burnt out or worse (someone removed it).
 
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