BEW/PD Owners check your lift pump

It is not normal to be able to hear the pump with the engine running.

Check that your hoses are hooked up the right way. Arrow pointing out for fuel supply to the engine, black hose. Arrow pointing in, return from the engine, blue connector.

Thanks Dan.............I'll check that.

When the key is cycled to on the pump will run until pressure is built up then stop. Once you start the car the pump then will run as needed to supply fuel. Can't help you with the sounds like its cavitating. That being said it has to be pulling air from some where.

Fuel lines look correct...........I agree, the system must be getting air from some where.

When the car is idling it sounds like it has a tire leaking air? Very easy to hear from inside/outside the car.

Thoughts? Pull the pump? Anything inside that I can look for that might be wrong?

Thanks

Jamie

Video of Noise

Hello Everyone,
I took a quick video with my phone of the noise.......its not great, but I hope you can get the idea of the noise.

http://www.youtube.com/watch?v=fF_i5aCylEc

The brushes may seat and the noise abate, after a few hours run time. I know of one person that this happened to.

Otherwise, not much to offer.

Thanks Dan for the feedback

I'll let it go and see what happens

Has anyone had a replacement (VDO) lift pump fail? They seem to last really well. I have about 110,000 miles on mine (original failed at 46,000 miles and actually was replaced under the VW new car warranty. Free tow to VW too. Took them a week due to lack of a new pump). I carry a replacement and wonder if I should change it out.

--Nate

I have yet to see one fail.

PDJetta said:

Has anyone had a replacement (VDO) lift pump fail? They seem to last really well. I have about 110,000 miles on mine (original failed at 46,000 miles and actually was replaced under the VW new car warranty. Free tow to VW too. Took them a week due to lack of a new pump). I carry a replacement and wonder if I should change it out.

--Nate

Click to expand...

Sell it and that spare relay 109 rattling around in your glove box.

It is common to hear it "cavitate" when you turn the key. Should be minimal though.

Mine squishes a little when the tank is near empty, but with a full tank I can't hear a thing. Mine is the white (I think) replacement.

Hi: I have a 2004 Jetta TDI with 345,000 kms. The lift pump failed May 16, 2012 causing the car to quit driving down the road and unable to re-start. Obtained a new pump from TDI Club recommended supplier (which saved me lots of $$) and had local VW Dealer install (also did diagnosis). The new pump just failed again (13 mths 60,000kms later ) - this time on the highway where the car lost power a few times before totally stopping - made it to an exit luckily. Had it towed to the VW dealer who again diagnosed the pump as the problem. This time they insisted that it would need a new gasket at $25. - before looking at the old one. The first change there was no gasket sold to me. Here is my question: would the fact that a new gasket was not installed at the last repair have contributed to the early failure on this pump? Alternatively, am I being gouged for a potentially unnecessary gasket this time?

- Dave

I have never had to replace the seal/gasket. No leaks on probably 20 changes.
But, it would be quite reasonable to replace it, especially if you had to re-do the job if it leaked.

This is the first failure of the new style pump I have heard of, and in a surprisingly short time.

DanG144 said:

This is the first failure of the new style pump I have heard of, and in a surprisingly short time.

Click to expand...

Note that the dealer diagnosed this failure. I would be suspicious of their diagnosis.

There is an arrow on the top of the pump that should be pointing straight back (not the arrows by the inlet and outlet tube - an arrow by itself.

http://forums.tdiclub.com/showthread.php?t=225672 see post #5.

If that is correct then it could be a slight resistance change in your level sender from the last one. There is about a 6 liter correction that you can do with VCDS.

'B' vs 'non-B' pump

My experience from 2012 is that my original ('B' suffix) pump started being noisy all the time, although the car still ran fine. (2002 VW Golf Tdi 1.9 PD engine)

I tried and failed to locate a 'B' suffix pump, so got a used 'non-B' pump for about £40, which has been working fine ever since.

I was initially concerned that the new design of pump would result in an undriveable car when the lift pump failed, but in fact I have found it is not quite that simple - at least with my car. The car will indeed not run with the new pump UNLESS the tank is more than about 1/3 full. If the fuel is above the required level then the fuel seems to be pulled through just fine. I'm not sure why this should be, but it does suggest that if the new pump fails and the fuel level drops to a point where fuel cannot be drawn up by the tandem pump(?) then adding a couple of gallons of fuel to the tank should get it going again.

Since replacing that pump I have become interested in maximising fuel efficiency, and I notice that the pump uses a full 3.7A of electrical power, which of course has to be generated by the alternator using diesel. The electrical power needed to run the car with engine running but no lights, wipers, blower motor, etc, is just 7.4A, so half of that electrical base load is down to the lift pump.

In fact I've modded the car so I don't use the alternator, but charge the battery off the mains every night, and that does save about 8% on fuel overall, so my issue is not directly to do with fuel consumption, but more to do with extending my alternator-free driving range. Switching off the lift pump would double my day-time fine-weather driving range. I'd quite like to fit a switch that I can press if needed to prime the fuel lines for starting (although I'm not sure that is even necessary) and then leave in the OFF position for normal driving.

For those ordinary mortals who use alternators, doing without a lift pump should save some fuel, although for me it's about putting less strain on my battery.

For my car the mpg hit if using an alternator is about 0.25mpg per Amp of electrical load, so the lift pump would decrease mpg by about 1mpg. However, a previous poster reported improved mpg when his/her lift pump was not working of around 3mpg, and that, from my experience, is way above the saving one could expect as a result of lower electrical load. I wonder if the improved mpg was down to a higher fuel temperature as a result of the fuel not being circulated back to the tank. If that is the case then even with my alternator-free arrangement I might see improved mpg.

It looks like if I fit such a lift-pump-kill-switch I'll also need to mod the fuel pump to allow pull-through at any fuel level in the tank. Apologies if this has already been linked to here, but can anyone point me in the direction of some instructions on how to perform the mod for the 'non-B' pumps?

A non functioning lift pump may put more stress/overload on the tandem pump.

suspect lift pump

I have an A4 B7 cabriolet 2.0 Tdi S line, over the past couple of months I've had a situation where if I leave the car standing for a couple of days it'll initially start fine but die, then I have to crank the hell out of it, it will eventually start like a dumper truck, then it'll be fine all day, it's like it ran out of fuel, I added a check valve on the fuel line just before the filter to eliminate air leaks in the system around the filter and tandem pump but it made no difference, it's almost like the pump motor sticks after it's been sitting idle for some time, I have a new lift pump on order.

An air leak will still allow it to drain back, through the return line, even with your check valve in the supply line.

You should be able to test your lift pump easily enough?

the idea is the check valve holds the supply line full, it doesn't matter if the return line is empty, even with a small amount of air in the supply line it should start easier than it has been, I think the lift pump may actually be dead, the tandem pump will eventually pull the fuel up but once started the system will be full so it'll start easily, the initial start is on the fuel trapped in the high pressure side, we did a service recently and fitted a new fuel filter and although warm it took some cranking (almost to flat battery which is new) if the lift pump was working it'd prime the filter almost instantly. I'm getting no codes at all. when I say starts easily I mean it's great, I don't think the engine does a single revolution and it's alive.
Just a thought, does the pump have its own fuse?

Yeah, I understand about the check valve, and you have stated it correctly. It keeps the supply line full. But this is only from the tank to the check valve.

The way these systems are built, an air leak in the rest of the system can allow the filter and the entire system (except for your few feet of supply line) to empty back to the tank.

Yes, fuse 28 on the VW Mk IV, not sure of the Audi B7. You should easily hear your lift pump under the rear seat, left side, if it is running.

No whirring sounds just a clunk noise another reason I think it's a jammed or busted motor, anyway low fuel pressure on the engine side of the tandem pump would surely register a fault code?

Nope, it surely will not. No sensor there.

On the VW's anyway.

well the pump is ordered so I'll let you all know how that works out, we have searched for leaks and found nothing

Good thread.
Does anyone have pics and instructions on how to modify the aftermarket one that was written about in this thread so it could operate like the oem lifts ?
Thanks

I no longer suggest doing the modification. It is hard to do the mod in a fashion that is high enough quality to add the "pull through mode" without adding unintended failure modes that actually increase the unreliability.

I will keep a spare handy. Thanks.

hi guys which pump is the best to get? they have on ebay from $68 to $285 in tank fuel pumps for mk4 tdi 2006 Golf

im confused

does all in tank fuel pumps have electronic lift pumps that gives 5 psi pressure ? or only the expensive ones?