B5.5 Passat TDI BHW cranking but not starting situation

I guess it's my turn for the no start situation.

Turn the key to glow plug position, I can hear the normal tank fuel pump initial noises. Turn the key further to crank, engine cranks over, starter speed sounds and looks normal. Keep cranking will not catch and crank until the stop oil pressure warning comes on.

VCDS does not detect any fault codes. But this is the cranking information I screen printed.




Car was running good two days ago. Parked it all day yesterday.

Last week, I took the front end to service position to replaced the power steering pump, idler/tensioner pulley and A/C tensioner pulley.

Any ideas and procedure to start with? Much appreciated.


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Update: I pulled the fuel line coming from the firewall to the fuel filter and no fuel will not spit out when I turn the key or crank.


I swapped the fuel pump 373 relay with the cooling fan 373 relay. Still no start.

I tested the power. When turning the key I get an initial power of 11 and something volts then zero. When cranking I get 10.5 + something volts.

When the pump is plugged back in, I do hear the initial normal "spoosh" sound. But still no fuel spitting out of the firewall line.

So, I take it I need a new fuel tank lift pump?


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I have been searching online for a lift pump. I've been finding different part numbers. Does anybody have the latest part number for the pump?


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Update 2: I pulled the lift pump out and tested it with 12v power from my battery charger. Shot diesel in the air and all over the driveway. Oops.. I then looped it hose and seemed to work fine.

Installed it temporary back into the tank with the fuel lines connected. With the firewall fuel line unconnected from the fuel filter, I put the battery charger on the pump. It ran but the fuel just trickles out.

Is that fuel line a direct connection or is there other parts along the way that could be faulty? The lines seem buried inside undercarriage panels.

I hope someone answers this, because I feel like I am just talking to myself. lol


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The fuel line from the pump goes directly to the filter. Put a fuel pressure gauge on it and see what you get.

Thanks for the reply.

I'll have to acquire a gauge as I don't have one. What pressure should the pump put out?


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The pump in the tank is very low psi. It's about 10 psi iirc. Since you have jesus clamps holding the hose to the fuel filter housing putting in an inline fuel pressure gauge will be simple. Finding one locally will not be. Newer injection systems are all 45 psi or more and the gauges attach to the rail. The old school mechancial fuel pump carbd vehicles with 5 or so psi are getting rare.


I know this will sound like a dumb question but have you jacked up the car recently or bottomed out or ran over anything that may have damaged the fuel lines running under the car?

PickleRick said:

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I know this will sound like a dumb question but have you jacked up the car recently or bottomed out or ran over anything that may have damaged the fuel lines running under the car?

Click to expand...

It's not a dumb question, I went under there to check for for any damage or crushed lines. Nothing I can see. Someone looking at this thread, who may have the same problem, may not think about any crushed lines. So it's good you mentioned it.





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Update 3: I didn't find a gauge quickly enough to test the pressure. I am pressed for time, so I bit the bullet and purchased a new VDO pump.

Part number 3B0919050B

Installed it, connected my battery charger and fuel shot right out of the firewall hose. Primed it for a bit by connecting my battery charger, then reconnected the electrical plug and the the car started right up. Test drove it and runs well.
Glad it's working now!


One more question. I don't have the proper tool to remove the lock ring. I used a hammer and screwdriver. When I installed the ring, I tapped to tighten the ring until it wouldn't go any further, but I can feel the pump move down a bit when I push the top down.
I don't remember how the original was, but is that normal? Or do I need to tighten down the lock ring more to keep the pump from moving down.



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The pump should not move if the ring is fully tightened

Is this a plastic locking ring and plastic tank?


On fords they like to distort and are hard to install.

I bring a pot of water to boil then drop the lock ring in for a couple min. Goes on smooth after that.

The ring is plastic. I think it's pretty robust and probably will not get easily distorted. Maybe boiling will help with the install.




But I think I'll see if I can fabricate some sort of tool to tighten it down properly. At this point it is not leaking with a full tank of diesel, which I am grateful.



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The plastic ring is 100% stout on my excursion 45 gallon polymer (plastic) tank. Never the less it's a bear to screw on and off. Requires a mallet and punch to drive off.

I didnt leave the pot boiling with the ring inside. I got it to boil, took off heat and walked the pot outside with ring inside until i was set to install.

The should be no walking of the fuel pump assembly where it meets the tank. The o ring or flat washer should be very snug. Even after heating i had to snug it up with the mallet and punch. Getting it started without heat was near impossible

Would a strap wrench work?

PickleRick said:

... Getting it started without heat was near impossible

Click to expand...

The Passat's lock ring is really easy to start it without heat. Tightening with a hammer kind of makes me nervous that I might knock something loose in the new pump.



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zzdiesel said:

Would a strap wrench work?

Click to expand...

I stole that photo with the tool from a random search of a random car. The Passat's is not as exposed as that and a strap wrench probably would be hard to get in there.

Kind of looks like this.. Another photo I found..



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Dont knock...tap. Also parts on the 7.3 to knock loose but it holds well enough on pot holes. Mallet not hammer

Update 4: I purchase this tool from eBay.
https://www.ebay.com/itm/Portable-A...357007?hash=item33e3926fcf:g:OMIAAOSwJ7RYUDRJ

Works really well, BTW.

While tightening up the ring, my perceive notion that fuel pump was moving up and down was incorrect. What was actually happening is when I pressed down on the top of the pump, the top of the plastic fuel tank was flexing and made a rubbing noise. This initially to me looked like the pump was still loose. It was when I re-tighten the ring with the tool while pressing down, the ring made the rubbing noise. It was then I realized the top of the tank was flexing.

So actually I was able to tighten the ring down enough after all with the hammer and screw driver, and it was fine all along.


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