Car won't start? Check your Anti Shudder Valve

bhtooefr

TDIClub Enthusiast, ToofTek Inventor
Joined
Oct 16, 2005
Location
Newark, OH
TDI
None
Jason, can you edit your post to say...

1998-2003 New Beetle and 1999.5-2003 Golf and Jetta TDIs
;)

smat2hews, you're correct, BTW. The 1998 and 1999.0 New Beetle are the same as the 1999.5-2003 NB, Golf, and Jetta. :)
 

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
I wish I'd read this before I did an engine swap. Let me warn those who do engine swaps... I've seen this happen another time since I did it on mine...

When you are lifting the engine (or dropping it, whichever...) in place, you might as well remove the anti-shudder valve before attempting to install the engine. What happens is the engine will rock back and hit the firewall, and guess what? The anti-shudder vavle is the first thing to go... the three plastic tabs that hold the vacuum pot in place snap off with extreme ease.

Unless you are looking right at it, you won't notice anything is wrong. Then, when you go to start the car, you get the dreaded start/die problem. Without the plastic fingers holding the vacuum pot in place, the air sucking by the anti-shudder valve closes the valve and kills the engine. Then, without the suction of the engine, the valve opens up, allowing just enough airflow to start the engine again.

But no fear, faithful readers. A zip tie locked the dashpot back into place and the engine fired off like a champ!
 

2footbraker

Veteran Member
Joined
Sep 6, 2005
Location
Ontario, Canada
TDI
06 Jetta, 01 Golf
This sounds exactly what has happened to me a couple times. But I have a 2006 Jetta and can't find the ASV anywhere. Anybody have any idea where it is on A5's? This car only has 5000km on it. Why would the ASV be sticking already, if that is what it is?
 

joshgb

Veteran Member
Joined
Jun 18, 2005
Location
Cachagua, California
TDI
04 Jetta wagon black
2footbraker: I had the same problem on my 04 PD Jetta and I'll tell you how I fixed it...maybe someone else can tell you exactly what I did, because it was an exercise in mild panic and bad reading.
Went to start the car this afternoon and it turned heartily but would not fire. I was in a big hurry, so I ran inside fired up the laptop and hastily scanned the how-to for the asv valve, not noticing the pre-pd caveat. I ran back outside, didn't see the asv where I expected to but saw it (what I think was it) oriented the other direction ( perpindicular to the firewall rather than parallel to it) underneath the big rubber hose between the intercooler and the turbo. It didn't look closed, but was hard to see, so I gently pushed it in and out a couple of times. The engine fired right up.
 

2footbraker

Veteran Member
Joined
Sep 6, 2005
Location
Ontario, Canada
TDI
06 Jetta, 01 Golf
Thanks, I will have to look for that when I get the car back. The dealer said the intake flap valve was stuck, which from what I can gather on here, is the A5 equivalent to the pre-PD anti-shudder valve. They replaced it under warranty.

Josh, did your ASV have a rod going into it or was it moved my an electric motor? What part do you move to open/close it? There are no pics on here which show where this valve is on the A5 engine.
 

joshgb

Veteran Member
Joined
Jun 18, 2005
Location
Cachagua, California
TDI
04 Jetta wagon black
Well, again let me be perfectly clear that I am flying blind about this as I have not seen any pics either and haven't had time to really figure out what is going on.(If I have some time tomorrow, maybe I'll endeavour to take a pic and post it.).
On the other hand, I had the very same problem again this afernoon after I posted and fixed it quickly the very same way.

From what I can tell, the place where the asv would have been on a pre-pd has been indeed replaced by a motor (metal housing on the turbo inlet with an electrical pug coming in). But underneath the motor (directly under the turbo housing inlet) there is what looks like the asv (going by the pics at the beginning of Compu 85s how-to) but oriented the other direction. As far as I can tell, it is mechanical...hard to see under there, but there is definitely a mechanical rod protruding from the "asv looking thing" and I don't see any electrical component to it. The rod is what I moved back and forth, pretty much as Compu 85 describes for the pre pd.
Just speculation but I am wondering if perhaps the asv was not exactly replaced on the pd but was augmented with a motorized side to control the functions that Compu 85 refers to, leaving the mechanical asv to control simple on and off.
Again, not precisely sure about any of this yet but it got me down the road and back.
 
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Detachable

Member
Joined
May 16, 2006
Same here: 04 Golf. It seems to like to do it after a short ride and restart. I got it going again by pushing on the metal flange of the valve, not the rod. I've been posting here http://forums.tdiclub.com/showthread.php?t=149101
trying to get info on what to do about it. I mean I only have 40k, so gunked up, it should not be, yet, it must be sticking, because that is what works. I guess that would be covered under warranty though, but I'm the 3rd owner so...dunno.
 

UnderPressure

New member
Joined
Sep 24, 2005
Location
Sauk Prairie, WI - USA
TDI
His: '98 NB TDI, Hers: '00 Jetta TDI
My ASV stuck yesterday AM before work. I tried to fire it off twice, but it just wouldn't light. Instead of being late for work, I just drove the wife's TDI for the day.

When I got home from work, the first thing I checked on the NB was the ASV...sure enough it was *almost* completely closed. The same thing happened to another TDI I used to own, but when it stuck on that engine - it cranked over as if it had no compression at all. This engine at least tried to run, but couldn't due to the nearly choked off intake.

Lesson learned: I should have checked the ASV right away and honestly believe it ought to be one of the first things you check if your car won't start.

Matt
 

ycuklordz

New member
Joined
Sep 3, 2005
TDI
Passat,2002,blue
Hello ppl,
I own a 2002 2.5l V6 TDI,The other day it cut out and from what i remember reading about this valve on my old 1.9 TDI i figured the same thing happened to my V6 although an entirely different engine,it cut out and wouldnt restart a few moments after firing it up,i believe the V6 has this valve positioned at the rear centre right near the turbo and it has a metal adjustable arm.
I got someone to crank the engine while i levered against the arm and it fired eventually and i aint had any bother yet but will either clean it out myself or get a garage to do it
Just curious if this actually is whats at fault ?
Anyone got any good pics or a good idea about the 2.5L ?
 

joshgb

Veteran Member
Joined
Jun 18, 2005
Location
Cachagua, California
TDI
04 Jetta wagon black
Addendum to my last message: my problem turned out to have nothing to do with the ASV (fuel system instead) so I'm afraid my experience was just blind luck....
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
I don't recall many anti-shudder valve problems lately so that means there will probably be a bunch of them soon. Maybe this will put this post near the top of the hit list for a bit.
 

John_M

Member
Joined
Jun 10, 2005
Location
Connecticut
TDI
2002 Golf, silver
I had this happen today!

Thanks for the thread, I was sure it was the fuel system gelling. Checked the sender and it looked fine, so checked the boards again. Luckily I found this!
Sure enough, I popped the hood and there was the metal "flag" sticking up! Now if it would just warm up outside so I could take the darn thing out to clean it...
 

pmadden

New member
Joined
Oct 16, 2005
Location
Colorado, United States
TDI
Golf 1999 Black
saved me, too

Thanks for this post. It saved me a tow & potentially expensive repair runaround. I had the stuck-valve problem three or four times in the course of a few days a couple months back, and then never again since.
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
It'll get worse again in the winter. Might consider getting it cleaned.
 

Sheepfarmer

Well-known member
Joined
Sep 19, 2007
Location
Virginia
TDI
2003 Beetle
Thanks soooooooooo much!!!!! You just saved me a $200 tow bill. But I am not sure I understand how to actually fix the problem. As a woman, it is a challenge to get mechanical information from technicians.
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
La Conner, WA
TDI
... None :S
If your valve has stuck shut, simply moving it back and forth a few times may free it up. However, this usually points to the larger problem of a plugged intake. It's probably due for a cleaning, which requires unbolting it from the engine.

-J
 

SpamJ

Veteran Member
Joined
Sep 6, 2001
Location
Cable, MN
TDI
Jetta Wagon 2002 Silver
Bump from another forum Vet,
This problem reared its head on my wagon with 123K.

So who has the cheapest replacement intakes?
 

CTD&TDI

Veteran Member
Joined
Jan 25, 2008
Location
Blanchester,Oh
TDI
2006 Jetta TDI DSG Pkg?
would this cause my tdi to crank for a while before starting? when the motor is cold, starts fine. once the motor warms up, it generally cranks 5-10 seconds before starting. could it be caused by asv stickingclosed?
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
CTD&TDI said:
would this cause my tdi to crank for a while before starting? when the motor is cold, starts fine. once the motor warms up, it generally cranks 5-10 seconds before starting. could it be caused by asv stickingclosed?
Is that an A4 1999 you have? If so check the thread titled something like "Hard start when hot"?
 

Pretzel

Member
Joined
Apr 4, 2003
Location
Texas
TDI
'03 Jetta TDI wagon (Auto)
Shudder valve/EGR

Thank you for the advice; I will plan on cleaning both the EGR and intake off the car. I just passed 65,000, so it can't hurt I guess.
 

Jedda03SGP

Active member
Joined
Jul 3, 2007
Location
Glenshaw PA
TDI
2003 Jetta
Right on the money!

Thanks compu_85, your description and fix of this common problem saved my day. Does the anti shudder valve tend to stick more when the engine only runs for a very short time? I started up the car to move out of the garage, ran no more than 20 seconds, and the valve stuck. This is the first time this happened to me.

I will keep an eye on it, thanks so much.

Steve
 

Jon Linn

Veteran Member
Joined
Jul 16, 2007
Location
Fort Wayne, In
TDI
2002 New Beetle 160,000 miles
Wow, thanks again for the nice write up! Yesterday, my (new to me) New Beetle that i have for 2 weeks chose not to start and so I got it towed to the repair shop thinking it was the starter. Read this thread this morning and drove to the repair shop on the way to work and what do you know, it was the anti-shudder Valve.

From read the only temp. fix until getting the intake and EGR valve cleaned is just poping it out each time to start or maybe by moving the valve back and forth it will losen up a bit. Does cutting the vac. hose like what JasonTDI said work as well? Would I be cutting the hose to the EGR?

thanks again!
 

momdogz

Member
Joined
Dec 30, 2007
Location
Vermont
TDI
Jetta 1999
wish I had looked here earlier when my car did this a month ago! thanks for the great pics; now I can take care of it myself instead of getting it towed.
 

frenchfifer

New member
Joined
Apr 7, 2008
Location
Framingham, MA
TDI
2003 Golf
Thanks for the ASV advice

Hi Folk,

My car wouldn't start this morning - so I went to this source per the advice of many TDI enthusists. This advice was spot on. I'm still under my extended contract, so I'll have the Dealer replace the component.
 

NarfBLAST

Top Post Dawg
Joined
Mar 3, 2002
Location
Waterdown, Ontario, Canada
TDI
2001 Golf 5MT
Jon Linn said:
From read the only temp. fix until getting the intake and EGR valve cleaned is just poping it out each time to start or maybe by moving the valve back and forth it will losen up a bit. Does cutting the vac. hose like what JasonTDI said work as well? Would I be cutting the hose to the EGR?
They are two separate hoses, but, if you "cut" a hose and leave it open that may have an effect on your entire vacuum system. Spend some time tracing hoses and checking the vacuum diagram that is pasted near the front of the engine bay. Instead of cutting the hose for the ASV just disconnected from the T fitting and replace the T fitting with a straight fitting or put a vacuum cap on the end of the T where you removed the line going to the ASV, or leave the hose on the TEE and sick a golf tee or other object in the end to plug it. That way everything else would still work. If you are cleaning the intake you can keep it squeeky clean by also remvoing the vacuum line to the egr and capping/plugging it to prevent a vacuum leak. I've been playing alot with vacuum hoses recently, its fun. I tried running without an ASV but I prefer smooth shutdowns.
 
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whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
narf said:
I tried running without an ASV but I prefer smooth shutdowns.
My Beetle has something wrong witht he ASV and it has never worked in the year that I have been driving it. If I hook it up, it just doesn't start, so I actaully don't know whatmy car would be like with this "smooth shutdown" you speak of.

I should look into that someday. I'll add it to my "GTG things to do for me" list.
 
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