2003 E500 fuel pressure issue
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Joined: Feb 2016
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From: SF Bay Area
2003 E500
2003 E500 fuel pressure issue
96k miles. So a couple of months ago my car would randomly not start, then finally died while driving. I checked power at the sending unit with a test light, and it lit up. I ordered a new fuel pump (vdo brand) and it started right up, well I drove it about 300-500 miles and it died again. I figured it was a faulty fuel pump from the factory, I ordered a genuine MB pump installed it, still no fuel pressure. I hooked up the original pump and the vdo pump to a 12volt source, both run. wtf? I replaced the fuel pump relay, still no pressure. Any ideas of what this could be?
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'99 and '05 E55 AMG
Go to the "fuel injection" section at Pelican Parts.
http://www.pelicanparts.com/techarti...Index-W211.htm
http://www.pelicanparts.com/techarti...Index-W211.htm
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Thanks for the post bbirdwell. OP - if you have any questions about any of the articles you can scroll to the bottom and leave a comment in the comment box where one of our techs will get back to you. If you need parts help, I'm just a PM away. Good luck!
Thread Starter
Newbie
Joined: Feb 2016
Posts: 5
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From: SF Bay Area
2003 E500
Thanks for the replies. Pelican is where I got my parts from and my tech info in the first place, I went back and re-read everything then saw more and more talk of DME problems. Sinking money sign feeling set in, so I checked voltage directly at the pump, zero. Now I checked all the electrical connections, I found that the connector at the fuel sender side was a bit spread apart, I smushed it back to the proper size, plugged it back in, turned ignition to #2, 60psi.... and it runs
Still doesn't explain why the original pump runs off a 12v supply..
Still doesn't explain why the original pump runs off a 12v supply..
Thread Starter
Newbie
Joined: Feb 2016
Posts: 5
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From: SF Bay Area
2003 E500
Car has been acting up again it would start and just chug then die, but a few hours later it would start up and run perfectly. Now it won't start at all, fuel pressure is 0. I swapped in a pump that would run off of 12volts, still nothing. I ordered a whole new fuel sending unit, I hooked up a working pump to it plugged it into the connector (sending unit and working old pump out of the fuel tank) pump runs.... Install everything pump does not run. I hook up a battery source directly to the pins on the sending unit, pump does not run... Is it possible the pump is bad but will run without resistance (air) but once its submerged it can't?
