Volkswagen TDI PD "quacking" noises - nick62
My 2000 115BHP TDI PD Passat is making what I can only describe as a "quacking" sound!!!

Its coming from the top of the inlet manifold and I thinks its something to do with the EGR valve arrangement thats there. The "quacking" noise sounds like air escaping from one of the diaphragms and happens approximately every second at tickover speed.

The car is running fine, normal MPG and is using no oil.

There is a small air operated valve on the EGR arrangement, this appears to be working normally (operates when engine is turned off for approx 5 seconds and then returns to original position)

There are no signs of leaking or split pipes.

Any of you VW diesel experts have any ideas/suggestions?

Cheers,

Nick
Volkswagen TDI PD - mark
Hi Nick

Has this happen on my TDI PD Passat, I described it as more of a "passing wind" type noise.

VW service receptionist diagnosed it a failed ABS pump without seeing the car but after getting the service manager involved it turned out to be the EGR valve.

Replaced under warranty IIRC would have been around £120 if I was paying.

Looking at where it is under the bonnet its is very accessible and looks a doddle to fit if you try it yourself.

You should also notice the noise every time you lift off on the throttle if it is the EGR.

As always

Mark

Volkswagen TDI PD "quacking" noises - SjB {P}
>>>Volkswagen TDI PD "quacking" noises

That'll be VW's best attempt at the four sprung duck technique! ;-)
Volkswagen TDI PD "quacking" noises - Altea Ego
Ah my 105 TDI PD has just started to make a strange noise on lift off now and again. It sounds almost like a turbo waste gate type noise.



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TourVanMan TM < Ex RF >
Volkswagen TDI PD "quacking" noises - nick62
Mark,

Thanks for your quick reply and I would also agree with your description of the noise!

Is it normal that the performance of the car is not affected though? What could be the worst consequence of leaving it for now, (seems a daft suggestion, but I might be getting rid of the car soon). The noise isn't always there.

Nick
Volkswagen TDI PD "quacking" noises - rtj70
Might not have been quite a quacking noise, but earlier this year my Mondeo TDCi gradually lost power and would not restart. When you tried to restart it was a very stange noise from somewhere on the engine. Towed to a Ford dealer and it was a failed EGR valve. Suppose an EGR does its thing (i.e. exhaust gas recirculation) so a failed one might make the same sound on a VW or a Ford??? Of course mine didn't start and yours still running.

This all makes me wonder about EGR valves. Two have failed on the Mondeo now. Still in warranty and a company vehicle but annoying all the same.
Volkswagen TDI PD "quacking" noises - mark
Hi Nick

Performance was just about normal at round town speeds if anything there was a very minor loss of power/throttle pickup, but almost unoticeable.

At about 90mph on the (autobahn of course) there was a mild hunting/surging but again hardly noticeable plus a little extra smoke visible in rear view mirror.

I would say if you picked one up with this EGR fault as say a pool or hire car you would not be aware anything was wrong so minor was the effect. Only because it was my regular drive and I am very aware of the vehicle ideosynracies did I notice these differences. The noise was more of a give away though.

As always

Mark
Volkswagen TDI PD "quacking" noises - nick62
Right hand up me, because I've done nothing about this......... (I've hardly used the car over the last couple of months), but today on the M6, the car suddenly lost power when accelerating from third to fourth (at about 3,500 rpm) and would not rev beyond 3,000 rpm whatsoever.

I stopped the car and turned-off the engine for about five seconds and re-started and its been fine ever since, (I've covered about another 140 miles since it happened).

Can anyone tell me if this points definitely to an EGR failure please. It's not the MAF as I replaced this at 70K and the symptoms were completely different and there all the time. The cars only got 91K on it now.

Nick
Volkswagen TDI PD "quacking" noises - rtj70
All I can add (because two failed EGR's on a Mondeo TDCi):

1. First time EGR problems symptoms were it would not rev above 2000rpm easily. You could be in first or second with your foot to the floor and it would not accelerate well. And clouds of smoke.

2. When one failed and I ground to a halt (revving oddly and cutout in the end). When you tried to restart you got weird noises from under bonnet. I said before not quacking but not an electronic beep/buzzer. I wish I recorded it now it was so strange. It was closer to a quack than any beep and things on cars normally beep/buzz. Two RAC patrols fouund it odd too - one recovered me to home the other to the garage. The first took the engine cover off and found it baffling to locate the noise. But the EGR had failed.


I think 1. and 2. above were symptonms of an EGR failed in an open an the other in closed positions. No idea which was which.

I believe an EGR causes fault codes which can be picked up.

What I find annoying is an EGR can fail and cause all these problems. But the car does not need one apart from emissions reasons. On the Mondeo people are known to blank it off.

Rob

P.S. Mine went wrong first off with less than 30k and then maybe 38k on the clock!
Volkswagen TDI PD "quacking" noises - rtj70
nick62... just thinking, if you can record the quacking noise and post somewhere then we can listen and give an opinion. Maybe your phone has the ability to record and then you can put that file somewhere.

Other backroomers... where could nick62 put this file?
Volkswagen TDI PD "quacking" noises - Hamsafar
The valve in the OP sounds like an anti shudder valve, when these fail it usually just means the car won't start as no air can get in.

My VW EGR failed (well it's control solenoid) and I only got MAF codes.
I had no power, and lots of smoke.
The ECU looks for reduced MAF throughput to confirm EGR operation.
Didn't have any quacks though.
Volkswagen TDI PD "quacking" noises - jc2
It's much more likely to show smoke or other concerns if it fails "open" .EGR should only operate at part throttle-it should be closed at idle and full-throttle..>> The valve in the OP sounds like an anti shudder valve,
Volkswagen TDI PD "quacking" noises - nick62
it fails "open" .EGR should only operate at part throttle-it should
be closed at idle and full-throttle..>> The valve in the OP
sounds like an anti shudder valve,


What are the symptoms of the anti shudder valve failing? Do you know where this is sited on the PD Passat?

Oddly enough the car does seem to be slightly more "agricultural" in a noise/vibration way, but only at tickover, but I may be mistaken!
Volkswagen TDI PD "quacking" noises - nick62
I think I've sorted-out this problem as I did some work on the car about a month ago and have since travelled 2000+ miles without the "quacking" noise or the loss of power re-occurring!

I removed the EGR valve assembly AND the inlet manifold. The biggest pain were the two M8 nuts holding the EGR link pipe to the actual exhaust manifold as one was badly rusted, but it came loose with some gentle persuasion!

Both the EGR and the manifold were very badly encrusted with the tar like substance that coats these parts over a prolonged period of time/mileage. Most was removed with a plastic scraper and long screwdriver but various solvents (brake cleaner) helped.

The inaccessable areas of the inlet manifold were only cleaned sucessfully as I am fortunate enough to have a large ultrasonic cleaning tank. I suppose overnight soaking in petrol would also help, but this tarry stuff reall is HORRIBLE to deal with. It makes a real mess.

I would recommend anyone who is confident in tackling this to have a go. Its saved me about £150 (the cost of a new EGR).
Volkswagen TDI PD "quacking" noises - Micky
Quacking?
Volkswagen TDI PD "quacking" noises - rtj70
"Quacking?"

Well OP and me agree a weird "quacking type" noise came from the engine of his VW and my Ford TDCi. The RAC guy that came to me never heard such a noise before. I wish I recorded it....

OP Glad the car is back to working okay.
Volkswagen TDI PD "quacking" noises - Sprice
Give it a squirt with some duck oil?
Volkswagen TDI PD "quacking" noises - Micky
Quacking!! I wish my cars quacked. Is it an optional extra?
 

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