2009 OM642 No Start
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2009 Freightliner Sprinter
2009 OM642 No Start
Good afternoon! I've been lurking in the forums, but now I'm in need of the collective genius of the group. I've got a 2009 Freightliner Sprinter RV, that will crank but not start. The electric pump puts out the proper pressure, the fuel filter has been changed, and burped. On my Autel Scantool the rail pressure is only 120 psi while cranking. Using a high pressure gauge, I verified my HPFP is putting out 600 bar of pressure. This is my first OM642, and I'm trying to not tear it apart ***** nilly without a proper direction. Any advice or procedures would be greatly appreciated. Thank you!!
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2009 Freightliner Sprinter
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'17 GLS450, '14 GLK250, Grandpa's Roadster
OK, so what that means is the HPFP is capable of 600 bar at cranking speed, but it isn't putting out that much pressure under real operating conditions. I think the first thing to do is confirm the actual pressure is 120 psi, and if it isn't, correct that .
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Joined: Jun 2025
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2009 Freightliner Sprinter
Gotcha, is there a preferred spot to measure the pressure with a gauge? As far as the fuel system, it goes Electric Pump to the filter housing, to the HPFP, then it goes to the rail. There's what looks like a FP Regulator on the driver side fuel rail, at the front. Also, the pressure sensor for the ECU is on the rear of the passenger fuel rail, correct?
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Gotcha, is there a preferred spot to measure the pressure with a gauge? As far as the fuel system, it goes Electric Pump to the filter housing, to the HPFP, then it goes to the rail. There's what looks like a FP Regulator on the driver side fuel rail, at the front. Also, the pressure sensor for the ECU is on the rear of the passenger fuel rail, correct?
Pressure regulator can't be replaced as is calibrated over the rail from factory.
20$ an Openport interface and 40$ for activation of a real diagnosis software ( diagnosis is not faul reader instead it's a step by step conducted tests in decent English with pictures., schematics, etc.....).
For starting 230Bar is enough.
Last edited by trigital; Jun 9, 2025 at 03:13 PM.
