Fuel Rail alert for type 647 engines

[abittenbinder]

Here's a posting I also put on the "other" group site. A Sprinter owner was complaining that his dealer had relaced his Fuel rail (parts and labor-$1000). He didn't know why the rail needed to be replaced-here's why. The yellow zinc plated, steel
fuel rail is a distribution, storage, and damping component for the high
pressure fuel injection system. Both the type 612 and type 647('04 and
newer) engines have a fuel rail and both designs have a fuel temp
sensor at one end and a fuel pressure solenoid valve at the other end. The 612
engines now enjoy a big advantage-their fuel pressure solenoid is
replaceable(and not very expensive). The higher pressure 647 injection
system has had problems with field service replacement of it's unique(to 647) fuel
pressure solenoids. These were very sensitive to correct installation
torque and sequence of torque and the resulting torque is critical to
its operating duty cycle. DC has discontinued that solenoid(part# 5138007AA) as a spare
part and now offers the fuel rail COMPLETE only-as a service replacement.
You can purchase the temp sensor but the fuel pressure solenoid is
discontinued. Rail part# is 5137290AA about $730 retail. Again, this
is concerns the type 647 engine fuel rail only. Doktor Andy

[Altered Sprinter]

Another great link from the master himself, Thanks for your input Andy
Richard:thumbup:

[abittenbinder]

A quick correction-the sensor at front of fuel rails is not the fuel temp sensor-it is obviously the fuel pressure sensor-which monitors the rail pressure. Ireally need to stop posting late nights. BTW, the fuel rail-fuel pressure solenoid info is not covered by a TSB and it does not appear in the service manual. Service manuals are written prior to model introduction and by nature contain lots of outdated info. This info appears in parts dept. bulletins. Doktor Andy

[kkanuck]

Thanks for the heads up Andy, very much appreciated.


Can you describe the symptoms of a bad fuel rail on a 04 158 with 15K miles?

What makes me think I may be having an issue, is at 70 miles per hour, which is around 2600-2700 rpms, if I press down on the gas pedal slightly, going on a flat surface, or have a slight load on the motor due to weight of cargo, or a small hill on the road, I hear a load howl / humming noise. It seems like this speed and RPM seem to be the sweet spot to recreate this noise consistently. Sometimes it is pretty loud and annoying with the more load on motor, the more noise.

I am under warranty so I want to make sure if I qualify for any repair of this issue, I have it performed while under warranty. I have another 16 months and 18K m iles on my warranty, so there is no rush per se.

Many Thanks for any input on this.


cheers,


Tibor

[abittenbinder]

Thanks for the heads up Andy, very much appreciated.
Can you describe the symptoms of a bad fuel rail on a 04 158 with 15K miles?
What makes me think I may be having an issue, is at 70 miles per hour, which is around 2600-2700 rpms, if I press down on the gas pedal slightly, going on a flat surface, or have a slight load on the motor due to weight of cargo, or a small hill on the road, I hear a load howl / humming noise.
Many Thanks for any input on this.
cheers,Tibor

Lets clarify the term "bad fuel rail". If, for instance, a technician determines that a fuel rail is contaminated -that contamination likely involves the fuel pressure solenoid. If the engine is a late 647 such as yours- the rail would be replaced. If it were an earlier 612-the rail could be disassembled(remove pressure sensor and solenoid) cleaned and the solenoid and possibly pressure sensor replaced without discarding the rail.
Or, if for example, the solenoid was malfunctioning- the entire rail would be replaced on a 647 engine. Symtoms of a malfunctioning fuel pressure solenoid can vary but because combustion anomalies would likely result- one would expect symptoms of abnormal diesel knock and/or rough engine operation. Doktor Andy

[kkanuck]

Can you describe the symptoms of a bad fuel rail?

What makes me think I MAY be having an issue, is....

At 70 miles per hour, which is around 2600-2700 rpms, if I press down on the gas pedal slightly, going on a flat surface, or have a slight load on the motor due to weight of cargo, or a small hill on the road....... I hear a load howl / humming noise.

It seems like this speed and RPM seem to be the sweet spot to recreate this noise consistently. Sometimes it is pretty loud and annoying with the more load on motor, the more noise.

ANY IDEA WHAT THIS COULD BE?

Thanks for any tips,


Cheers,

Tibor

[talkinghorse43]

Might be what you're hearing is what I also hear with my '02. Others seem to have heard it too - go to yahoo sprintervan and look at the thread beginning with msg 26957. I don't know what the noise is due to, but I suspect something to do with the turbo or exhaust. Anyway, I cruise at a speed (70 mph indicated) just below the noise because I've found that cruising with the noise results in significantly reduced mileage.

[kkanuck]

Thanks Talking horse, I will look up that message thread.

Have you ever had a tech look at it or complain about it to a dealer?

[talkinghorse43]

Never complained about it, in fact, I kinda like it. But, my ears have never been very sensitive. Plus, it doesn't sound or feel like something that would cause damage (not mechanical in origin).

[Altered Sprinter]

Hi Guys
Andy has posted some great information for us but to avoid duplicate threads, it may pay to follow this link Turbo Resonator Problem - Sprinter-Forum.com (http://sprinter-source.com/forum/showthread.php?t=796)
As to not resolving the issue so much, but as to the reason why?
Richard