Please help. Is it my fuel pump?

S

SplintertheSprinter

New member
Hi everyone. I love my 2003 sprinter 3500. This is my first sprinter and it was getting 21 miles per gallon on the highway. It's a dually, has lots of rust LOL but it ran like a champ. Now after driving to the diner for breakfast on Monday morning it wouldn't restart. I had it towed home on a flatbed, then it started after unloading it off of the truck LOL. I had a filter previously purchased so I changed it now it won't restart again. I primed from the filter to the low pressure pump and removed all of the air bubbles but I believe the tank pump is faulty? Can someone please help me? This is my first diesel also. I did remove the line from the tank to the filter and turned over the key and nothing came out so I am assuming the pump is bad in the tank. This is also my first thread and for him ever LOL so I hope it works getting some good advice thank you
 
sailquik

sailquik

Well-known member
SpintertheSprinter.
You have a 2003 Sprinter with the OM-612 engine....right?
There is no pump in the fuel tank.
That was added in 2004 when they changed to the OM-647 engine.
You need to really seal up all your fuel lines.
The pump on the top front of the engine has to draw fuel through all to lines from the fuel tank.
Any sort of tiny vacuum leak, and all the fuel drains back to the fuel tank and you won't
be able to start the engine.
When you removed the fuel line to the fuel tank, you made absolutely sure that there would be
no fuel in the line. It all ran back into the tank.
There is no check valve between the fuel filter and the tank, and no pump in the tank, so any
tiny vacuum leak between the LP pump on the top front of the engine and the fuel pickup
in the fuel tank and the pump cannot prime itself.
Hope this helps,
Roger
 
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SplintertheSprinter

New member
Thank you so much sailquik. I did prime the fuel lines from the filter to the low pressure pump using a temporary hose and pushed all of the air out of the outlet on the low pressure pump. There are no visible bubbles in the clear lines. I then reattached the supply hose from the tank to the filter and tried to start it. Shouldn't the engine start by using what fuel is in the lines and the filter? What is odd is I called my local auto parts stores and they both look up 2003 Dodge sprinter 3500 2.7 CDI as having a fuel tank pump? Isn't it odd that putting the sprinter on a flatbed allowed it to start back up? But I did notice that it was surging a little. Also I crawled underneath and noticed there is a round section on the bottom of the fuel tank which is a clue that there is a cylindrical fuel pump inside?
 
blfmtriv

blfmtriv

living in the Top End NT
gday splinter

mate i have been in the exact same boat, searching and search for the illusive tank pump, i even had a fuse allocated, dropped the tank and opened it, no pump, that round piece on the tank bottom is where the sender unit sits, i replaced all hoses and clamps, replaced filter with a non WIF sensor, now runs like a champion,:thumbup:
 
S

SplintertheSprinter

New member
Lol thank you for the info blfmtriv. I'm still puzzled why the auto parts stores list a tank fuel pump for that model sprinter? I think tomorrow I will try to pump manually fuel from the tank then plug the hose with my thumb and quickly place it on the filter because as I said earlier I don't have any air bubbles in the supply lines to the low pressure pump. I need to get the "Splinter" up and running as quickly as possible I need it for my job. of course I checked the 15 amp fuse and it was good so I'm completely scratching my head as to why it didn't start with the fuel from the filter alone?
 
Ciprian

Ciprian

Spark Plugs not allowed!
You've been told a couple of times that you do not have an in tank fuel pump. You still insist that you do. Take the fuel tank off and convince yourself.

Sent from my SM-G900P using Tapatalk
 
sailquik

sailquik

Well-known member
SplinterTheSprinter,
OK, Are you located in the USA?
If you are, then there is no pump.
Do you have the OM-612 2.7 liter inline 5 cylinder engine (found in all 2001-2003 Freightliner and
Dodge Sprinter vans in the USA).
How about you click on "sailquik" at the left here, above the avatar photo, and then click "send email to
sailquik".
Send me your VIN # and a valid return email address and I will pull the parts diagram for your Sprinter's
fuel system.
I'll also send you back the OEM Build Data Card for your Sprinter listing all of the options that went into
assembling your Sprinter.
Roger
 
S

SplintertheSprinter

New member
Hi Roger, thank you for the help. As I said in my first post I am a total rookie when it comes to diesels and this is my first sprinter LOL. Yes it is in the USA and unfortunately I'm at work now finally after three days LOL. I had to get my Chevy express running again because the sprinter is off the road now. Downsizing stinks LOL. As soon as I get home I will email you the Vin #. Thank you everyone for your advice. I will definitely pay forward in the future.
 
MercedesGenIn

MercedesGenIn

Mercedes-Benz Resource
Hi there, could be split o ring on fuel rail pressure regulator if u have no joy with other things
Don't discount that it may be failed cam or crank sensor as synchronisation error here would prevent starting.

All the best Steve
 
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SplintertheSprinter

New member
Hi Steve, thank you for the advice. Maybe that would explain why it started after it was put on a flatbed? Having the engine high in the air could have vented any air out of the line? I'm going to prime the system and replace clamps and check O-rings this weekend I sure do miss driving it LOL the sound of it is awesome so I'm bumming right now not having it on the road
 
C

clydedillman

New member
sailquik said:
SpintertheSprinter.
You have a 2003 Sprinter with the OM-612 engine....right?
There is no pump in the fuel tank.
That was added in 2004 when they changed to the OM-647 engine.
You need to really seal up all your fuel lines.
The pump on the top front of the engine has to draw fuel through all to lines from the fuel tank.
Any sort of tiny vacuum leak, and all the fuel drains back to the fuel tank and you won't
be able to start the engine.
When you removed the fuel line to the fuel tank, you made absolutely sure that there would be
no fuel in the line. It all ran back into the tank.
There is no check valve between the fuel filter and the tank, and no pump in the tank, so any
tiny vacuum leak between the LP pump on the top front of the engine and the fuel pickup
in the fuel tank and the pump cannot prime itself.
Hope this helps,
Roger
Click to expand...
That's good information. The fuel lines on the 2003 are a bitch.all kinds of issues. Best thing is to fill filter and if necessary fill fuel line to the low pressure pump. Make sure you get the water separator on the filter properly sealed. Even experience sprinter mechanics have issues with these filters
 
KingSprinter

KingSprinter

New member
SplintertheSprinter said:
Thank you so much sailquik. I did prime the fuel lines from the filter to the low pressure pump using a temporary hose and pushed all of the air out of the outlet on the low pressure pump. There are no visible bubbles in the clear lines. I then reattached the supply hose from the tank to the filter and tried to start it. Shouldn't the engine start by using what fuel is in the lines and the filter? What is odd is I called my local auto parts stores and they both look up 2003 Dodge sprinter 3500 2.7 CDI as having a fuel tank pump? Isn't it odd that putting the sprinter on a flatbed allowed it to start back up? But I did notice that it was surging a little. Also I crawled underneath and noticed there is a round section on the bottom of the fuel tank which is a clue that there is a cylindrical fuel pump inside?
Click to expand...
Can you supply me with your VIN? I believe you have the 612 engine, its pretty easy to identify it as it is the one that has all the clear plastic lines. I currently have one in the shop with this same concern, it will re-start when it has had a chance to cool down, then after driving will not restart and there is air present in the lines.
It is true, there is a place for the fuel pump fuse. When I first started working on these vans I had one with a similar concern and found out there was indeed, no fuel pump. The fuse was just chillin in the slot.
Anyways, those engines are known for the clear lines cracking and braking, I would try replacing those lines before anything else. There is actually a recall on those that a lot of vans have not had done where you replace the intake manifold due to a freeze plug blowing out. You might check that out, odds are yours has not been completed and you may sweet talk you local MB dealer into replacing all those plastic lines for a discount! BUT!!!! Make sure they replace all three of the plastic lines, and if they give you the "we cant get those parts anymore" its BS, we keep those in stock at my dealer! hope this helps!!!
 
KingSprinter

KingSprinter

New member
KingSprinter said:
Can you supply me with your VIN? I believe you have the 612 engine, its pretty easy to identify it as it is the one that has all the clear plastic lines. I currently have one in the shop with this same concern, it will re-start when it has had a chance to cool down, then after driving will not restart and there is air present in the lines.
It is true, there is a place for the fuel pump fuse. When I first started working on these vans I had one with a similar concern and found out there was indeed, no fuel pump. The fuse was just chillin in the slot.
Anyways, those engines are known for the clear lines cracking and braking, I would try replacing those lines before anything else. There is actually a recall on those that a lot of vans have not had done where you replace the intake manifold due to a freeze plug blowing out. You might check that out, odds are yours has not been completed and you may sweet talk you local MB dealer into replacing all those plastic lines for a discount! BUT!!!! Make sure they replace all three of the plastic lines, and if they give you the "we cant get those parts anymore" its BS, we keep those in stock at my dealer! hope this helps!!!
Click to expand...
Also it is important to note, cranking the engine to "PRIME" the fuel system will burn up your high pressure pump. You need to remove the plastic line that feeds pre-pump, the little pump above the high pressure pump, with fuel before cranking!
 
G

galvinize

Active member
2003 T1N passenger van 201,000 miles

I’ve been through several fuel line issues, and air bubbles in the clear lines was the frequent culprit . But since you don’t have bubbles, you may skip the usual air-leak remedies: (replace the fuel filter, and all the O-rings at the filter).
Have you checked your high pressure pump? I’ve needed to replace mine twice.
 
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autostaretx

autostaretx

Erratic Member
You (or anyone) can also enter your VIN at any of these sites: https://www.datamb.com/ , https://www.lastvin.com/ , http://mbepc.net/f/vin/ http://mb.vin/
to download a free copy of your "datacard", what MB built into *your* printer.

KingSprinter (and member sailquik) can also supply the info, and their lists will also have the sub-assembly serial numbers (extra info sometimes helpful when chasing down bizarre parts)

A 2003 in the US will be an OM612 engine: engine-driven low-pressure suction fuel pump, instead of the electric in-tank pump of the OM647.

--dick
 
sailquik

sailquik

Well-known member
OK, here's the "ultimate test" for 2001-2003 USA Specification Dodge and Freightliner T1N Sprinters with the OM-612 2.7 liter
5 cylinder engine.
Disconnect the fuel line that runs from the fuel tank to the fuel filter.
Turn on the ignition key for a few seconds.
If you don't hear a pulsing noise (the in tank fuel booster pump that is in 2004-2006 USA Spec. T1N Sprinters) then there is no electric fuel pump
in the fuel tank.
Try the same trick on an '04-'06 with the OM-647 2,7 liter 5 cylinder engine and you will have a nice mess as the in tank booster pump pushes
fuel up to the low pressure fuel supply pump on the top front of the engine.
The round area in the floor of the fuel tank is in all Sprinter tanks as that is where the mesh fuel strainer fits over the fuel pick up.
Roger
 
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