Car won't start? Check your Anti Shudder Valve

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
Springfield VA
TDI
1999.5 Jetta GLX TDI
Car suddenly won't start? Check your Anti Shudder Valve

In the chat room, there have been a couple of guests whose cars would not start because the anti shudder / intake changeover valve was stuck closed. I'm writing this so that people not familiar with the shudder valve can see if it is stuck from looking at it.


On the passenger side of the engine, looking on the side next to the firewall you'll see this:



The black plastic arm to the left of the round silver thing is what operates the shudder valve. This is a throttle plate which closes completely, preventing air from getting into the engine. It closes when you turn the key off to make shutdown smoother, and as a backup way to kill the engine. If it should get stuck closed, the engine will not start, as it can't get air.



In this picture, I'm holding the valve closed with my finger. Notice how the metal bit is pointing straight up now, and you can't see the top of the diaphragm on the dashpot anymore?


Here are some closer pictures:

Open (engine can start):



Closed (engine can't start):



Again, notice how the metal bit is pointing up now?

If the valve is stuck, try pulling up where you see me pushing down. It should spring back to the open position.

If you take the rubber elbow off from the intake and look in, you will probably see lots of black goop:



Don't scrape this out when the intake is attached to the engine as some could fall in, and get stuck inside, and bend a valve. That will ruin your day. Refer to the intake manifold cleaning procedures found elsewhere on the forums. This picture also shows the valve open... it's the flat round bit with the layer of gunk on top.

This info only applies to the ALH engine found in 1998-2003 Beetles, and 1999.5-2003 Golfs and Jettas. The A3/B4 (96-99) cars don't have this valve, and on the 04+ (PD) cars, it's moved by an electric motor, and actually closes some while the engine is running to draw in more EGR. It's theorized that this flap getting stuck or remaining closed is what causes the hesitation on the 2.0 PD engines found in the 04 and 05 Passats.

If you have checked this, and the valve is open, and the car also stalls sometimes when your driving, consider checking your Relay 109, which supplies power to the engine computer and is known to fail. If the glow plug light does not come on then go out when you turn on the ignition, this relay has likely failed.

Hope someone finds it useful! :)

-Jason
 
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ColoradoRich

Member
Joined
Feb 2, 2005
Location
Colorado Springs, CO
TDI
Golf, 2001, silver
Wow! This was a BIG help! Thank you Compu 85

Well, last night my Tdi died and I had to have it towed to my local repair shop (about 12 miles). I thought I might have a battery problem but later thought it might be a fuel filter problem. THEN ... this morning I did a search on this forum and found this link. I went to the repair shop (which, fortunately was still closed) and pulled the "anti shudder valve," which was stuck in the "in" position.
It started immediately! Whew! I had visions of having to have it towed again to a local stealership.
Thank you so much for taking the time to post those pictures to SEE what you are talking about. Our language has it's limits with describing auto parts and locations.
Coloradorich
Tdi Golf, 2001, 160,000 miles.
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
Great pictures. Many times people will say that their car won't start when warm and this is very often the problem, correct?

Or they say their car won't restart after shut down.

Planning on linking this in the How-to section?
 

KansasTDI

Veteran Member
Joined
Oct 21, 2005
Location
Overland Park, KS
TDI
2003 Black Jetta Sedan, 5M SOLD NEW 2003 VW Beetle TDI 5M 95000 miles
This happened to me this morning.
Car would try to start for brief second and then just cranking the engine.
I appreciate the help from all of the board members.
 

bhtooefr

TDIClub Enthusiast, ToofTek Inventor
Joined
Oct 16, 2005
Location
Newark, OH
TDI
None
Link it in the how to section, and I'm nominating this thread for sticky status.
 

LarryLymb

Veteran Member
Joined
Apr 13, 2002
Location
Lehigh Acres, FL
TDI
Jetta TDI Wagon 2003 Mojave Beige, 5 speed
I have noticed a couple of similar starting problems. One, sometimes if I immediately try to start the car before the computer has had time to run thru its start up procedures, the car won't start. And two, sometimes if I insert the key upsidedown (with the key holder slot towards the top) the immobilizer icon lights up on the dash and the engine will start but immediately die. Anyone else notice either of these symptoms?
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
12' RAM 2500 QC,LB. 2019 Cherokee 2.0T
You can cure the problem temporarily so you don't have to unstick it by cutting the vacuum line to it. The long term cure is to clean the intake and EGR.
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
Springfield VA
TDI
1999.5 Jetta GLX TDI
Don't try to pull the vaccuum line off the dashpot, you will break the nipple off, like I did, and end up rebastardizing it on. (see the glue in the pictures?)

Oh, and I allready put a link to this in the how-to section... but its on page 2...

-J
 
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jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
12' RAM 2500 QC,LB. 2019 Cherokee 2.0T
That's why I said to CUT it! Couple it together or use a new line once you carefully cut it off the nipple when it's OUT of the car.
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
Springfield VA
TDI
1999.5 Jetta GLX TDI
Exactly! Just wanted make the point doubly clear... "Oh, he says to remove the line... I bet I can just pull it off... "
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
12' RAM 2500 QC,LB. 2019 Cherokee 2.0T
You just know someone is going to be like "you said to pull it!" Waaahhh!!!! Numbskulls!
 

ronenb

New member
Joined
Feb 11, 2006
TDI wont rev-up

I have a 1998 Beetle TDI 5 speed and have a problem with the car reving up past 1200-1300 rpm's. If I let the car the car idle for 12/hr to 45 mins. it runs fine. However, the next moring the car won't rev up again and can't get to even speeds of over 20 MPH. If I try to rev up the car higher than 1200 the motor stutter and smokes black smoke very bad, but when I release the gas peddal the car resumes to idle perfectly. Since developing this problem I have tried replacing the fuel filter, air filter, fuel shut off valve with not results. Please help.

Thank you in advance,
Ron

ronenb@aol.com
 

lance71137

Well-known member
Joined
Jul 14, 2003
TDI
Jetta,03,Blue
Can some one please give me a link to the "how to" section that Jason is talking about.
Thanks,

Lance
 

lance71137

Well-known member
Joined
Jul 14, 2003
TDI
Jetta,03,Blue
Is there a procedure or "how to" on how to clean a clogged EGR? So far I have seen how to identify a stuck EGR, and a "How to" on a Mod to avoid clogging in the future. But I have not seen a "how to" on how to clean if it happens again

Thanks,

Lance
 

Blauwagon

Well-known member
Joined
Jan 26, 2003
Location
Goffstown NH
TDI
JettaWagon,2004,Blau
great pics, I use the anti shuuuuder valve to stall the engine when working under the hood
 

soupaman305

Well-known member
Joined
Jul 20, 2005
TDI
2000 Golf IV GLS TDI White
cleaning the EGR and the intake is def worth it. i cleaned my EGR and the exhaust supply line today and it was nasty! just make sure to follow this step, Remove two #6 cap screws from the exhaust supply line leading from the exhaust cooler to the EGR. Don’t loose the thin metal gasket.
i lost the metal gasket.. i got lucky though because it went all the way to the bottom on the skid plate and i was able to get it with just jacking up my car. great thread!
 

nosparkplugs

New member
Joined
Jun 29, 2004
TDI
'03 Tornado Red Golf GL TDI
good info and pics. happened to me this weekend so came here to see if there were other reports. I guess the problem isn't that uncommon. 2003 golf never had a problem before. symptoms as stated above. car cranks, hits on a cylinder or two and then nothing. cranking sounded unusual. higher pitched as if constricted... (hmmmm, why's that? I wondered). messed aroung two hours troubleshooting fuel supply. just before the air supply side got tore into, was cranking engine and when I stopped I heard click-click CLICK PUFFF (the anti-shudder fart) and knew instantly what the problem had been and that the car would now start. it did. felt SO stupid for not thinking about that earlier.
 

soupaman305

Well-known member
Joined
Jul 20, 2005
TDI
2000 Golf IV GLS TDI White
on a 2003 eh? how many miles does your car have on it? i'm wondering how long or miles it actaully takes to clog up the egr. i have 60k on mine and it was definatly time to clean it out but i'm wondering when someone should start to think about cleaning it out. i dont mean this question as a thread hijack but i think it may be relavent to the topic.
 

Bob_Fout

Oil Wanker
Joined
Sep 5, 2004
Location
Indiana
TDI
2003 Jetta - Alaska Green (sold) / 2015 GTI 2.0T
soupaman305 said:
on a 2003 eh? how many miles does your car have on it? i'm wondering how long or miles it actaully takes to clog up the egr. i have 60k on mine and it was definatly time to clean it out but i'm wondering when someone should start to think about cleaning it out. i dont mean this question as a thread hijack but i think it may be relavent to the topic.
There's no set miles or age that determines when it's clogged...the factors include... driving conditions (short trips or lots of highway miles), driving style (always shifting at 2000 RPM and/or pussyfooting it) and fuel (maybe?)
 

rk9721

Member
Joined
Dec 3, 2003
Location
NY, USA
TDI
JETTA, 2002, BLUE
thanks guys, my car had the same problem last night and looked at the anti shudder valver, pulled a little and the car started right up.
 

bozonechad

Member
Joined
Dec 27, 2005
Location
Montana
TDI
2003 Jetta Wagon GLS TDI
Thanks

Thanks for the pics. My valve got stuck yesterday and I was boggled on why my car would not start. I watch the small bubble in the fuel line go in and out as someone else turned it over. This forum rocks!
 

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
I had a variation of this problem when I did an engine replacement. On installation, the engine bumped the firewall and broke clips that hold the plastic body of the anti-shudder valve in it's metal frame. Since the valve is spring-loaded in the open position, it allowed enough air by the butterfly to allow the engine to kick, but then the valve sucked into the closed position immediately, killing the engine.

I'm not going to say how long it took to find that, but you only get burned by that problem ONCE. :-/ A ziptie holds it in place nicely.
 

air870

Active member
Joined
Mar 11, 2006
Location
bombay
TDI
octavia I
could anyone tell me if my non starting prob is caused by my glow plug light coming on and flashing . its started only after chipping my car . the engine doesnt crank sometimes when warm.i will be trying the valve thing as suggested and the procedure suggested on the glow plug check thread.
 

paramedick

TDIClub Enthusiast, Vendor
Joined
Jul 29, 2001
Location
Versailles, Kentucky
TDI
2015 Audi Q5 TDI, 2000 New Beetle
glow plug light coming on and flashing does not mean a problem with the glowplug system. It means the computer detects a "critical" error.
 

air870

Active member
Joined
Mar 11, 2006
Location
bombay
TDI
octavia I
found the fault. showed up in the scan. turned out to be impropper info supplied to jeff by me on the engine type.
 
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