engine light- throttle plate closed/stuck

MadGTI

Member
Joined
Jul 2, 2002
Location
Ontario
I'm surprise there is still no after market kit to replace the plastic gears!!!! :(

Mine just went the other day so i'm hoping i can just flip the gears out like Jenettless
 

Darth Scott

Active member
Joined
Apr 8, 2007
Location
Colorado Springs, CO
TDI
2002 JSW TDI
FWIW, my 240D, which has no EGR at all, also has a throttle plate connected mechanically straight to the accelerator pedal. ;)
Now I'm curious... if it's not controlling the EGR, what is that throttle doing? Is that acc pedal also, as I would expect, mechanically connected to the fuel delivery system? Try as I might, the only reason I can think of for this is to bring the engine RPMs down more quickly, meaning the throttle plate restricts intake when the acc pedal is released... is that how it operates?

TIA for expanding my education, I'm really interested in this. :)
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Now I'm curious... if it's not controlling the EGR, what is that throttle doing? Is that acc pedal also, as I would expect, mechanically connected to the fuel delivery system? Try as I might, the only reason I can think of for this is to bring the engine RPMs down more quickly, meaning the throttle plate restricts intake when the acc pedal is released... is that how it operates?

TIA for expanding my education, I'm really interested in this. :)
An MB expert could possibly explain better than I, but it would seem to help with noise too. It also seems to help them run better in the cold, and probably works as a better way for engine braking too. The later cars did away with this setup (and use an entirely different intake as well).

The vacuum-controlled DFI systems MB used to use way back when on their diesels really works more like a carburetor by using the throttle to force a vacuum (low pressure) in the intake which is how the fuel control rod was operated. There was no mechanical linkage from the accelerator pedal to the pump, the pedal just went to the throttle.
 

Greg Roles

Veteran Member
Joined
Mar 19, 2008
Location
Australia
TDI
Euro GT TDI PD 170 2008
I can't comment on what you guys have, but in my Euro model the EGR runs from it's own 3D map. The tuner I am working with found this for MKV TDI's with the EDC16+ ecu. Whilst this is indeed for the valve itself, information from Erwin suggests the flap also runs on it's own 3D map, and it's sole function is to create vacuum prior to the EGR valve to draw in exhaust.



I pulled the plug on my flap, and whilst it threw an error code and the car went into a limp mode and was obviously more "flat" performance wise, this cleared when plugged back in and error code removed via Vag Com.

Whilst unplugged the only difference I noticed apart from lowered performance was a bit of run on when shutting down. Engine braking, the one thing I'd expect a flap to play a part in, was identical. In my minds eye, this thing just pulls in exhaust gas, aids smooth shutdown, and is also used to help DPF regeneration when the car does one, for those like me hobbled with a DPF.

Ultimately I'm about to do away with mine altogether, and run a simple open / close shutdown / runaway flap just to be safe. I'll let you know what happens!
 

2footbraker

Veteran Member
Joined
Sep 6, 2005
Location
Ontario, Canada
TDI
06 Jetta, 01 Golf
Mine had nearly identical performance when unplugged. Aside from the slightly bumpy shutdowns and also exaggerated another boost issue I'm having. But my CEL persisted after plugging it in and need to be cleared with VCDS.
 

muellgre

New member
Joined
May 6, 2011
Location
Iowa
TDI
'06 Jetta
I believe I am having the same problem as the OP and many others in this thread, but want to try to verify this is the part I need because of the cost. I have an '06 Jetta TDI PD and have read a P2112 Throttle Actuator Stuck Closed after the CEL came on. The CEL is off/on depending on the day, but it is on most of the time. I do not hear any noise from the flapper motor as others have and I have noticed no performance or mileage difference (I drive 200 highway miles a day). I removed the tube going into the flapper valve housing and can see the valve and move it by hand (although I can feel the resistance of the gear). I read on this site that the flapper valve should close for a few seconds when the engine is shut off. I had my daughter start the car for a few seconds and shut it off while I was watching the flapper and it never moved. Can anyone verify that this flapper should in fact close after every time the motor is shut off? I don't mind trying to replace this part myself, but I hate to order the part and find out it's the EGR or some other problem. Thanks.

Gregg
 

muellgre

New member
Joined
May 6, 2011
Location
Iowa
TDI
'06 Jetta
I have installed the new ASV valve purchased from ECS tuning, but am still getting the same P2112 error code. First I have to say how easy it was to install this part, only took about 20 minutes and I want to thank all the members who described the process.

After I installed the new part, I left the tube disconnected to observe the flap valve while the engine was started and shut-down a couple of times. Again I did not see the valve move at all. I put the tube back on and decided to take it for a drive to see if the CEL stays off. It came on after about 10 miles of light in town driving. By the way, I did NOT clear the fault with a scan tool, but have discovered that performing the maintenance reset with the trip odometer and minute button turns off the CEL for a while, but it comes back on after a few trips with the car.

Does anyone have any advice on where I should be looking next? I'm still confused by the flap not closing when the engine is shut-down but I have no idea where to go next with this problem. Am I looking at something in the EGR? What is the EGR and it's function? Could the EGR be preventing the flap from closing on engine shut-down? Is it difficult to diagnose and/or replace?
 

slidewayz

Member
Joined
May 19, 2011
Location
Calgary, AB
TDI
06 Jetta TDI
I followed Jenettles? instructions - but without pics of knowing where and when to drill I smashed the plastic gear into 3 pieces - then saw where I needed to drill. Regardless, after gluing it back together - it works still. I have some basic pics, but at least they will help future fixers save themselves the $200-$600 depending on if they DIY or not.
My cost was $0. Time was over an hour all said and done.

I'd like to attach the pics - but don't know how. Can someone help?
 
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eldar2000

Member
Joined
Sep 10, 2011
Location
Indiana
TDI
2006 Jetta
I have the same problem that led me to this forum. The engine light on for code P2112(TAC systems - stuck closed). Thanks for the info everyone! I took the hose off today to see what was going on and the flap was not moving. I tried moving it and it wouldn't. I turned the car on and then shut it off and ran back to see if I can see the flap move/close, but it was not moving even though I could hear the motor working. I tried it again and this time gave the flap a bit of help to see if it will close. It did, but after another try it still would not close. Feels like the gears are stripped. I put hose back on until I have more time to work on it. The light is gone though! :confused:
Can I expect the light to come back on and if it doesn't can I be pretty confident that the flap is not working properly, since it's not closing? I imagine the light comes on when the gear strips and causes the motor/flap to lock in one position, or am I completely off base here? What actually causes the sensor to trip the code?
Also, during my search for a replacement Throttle body, I ran across this:
http://www.ecstuning.com/ES475916/ES475916/ - $47.28 for the ECS model, but $289.44 for the OEM model (http://www.ecstuning.com/Search/03G128063/ES1910133/). I haven't contacted ESC yet to find out if that's really for the same part or if I'm missing something. on the one for $47.28, it says: "This product has been superseded to ES#1910133".
If that works for my 2006 Jetta I will replace it for that price just for a peace of mind! :)
 

eldar2000

Member
Joined
Sep 10, 2011
Location
Indiana
TDI
2006 Jetta
I followed Jenettles? instructions - but without pics of knowing where and when to drill I smashed the plastic gear into 3 pieces - then saw where I needed to drill. Regardless, after gluing it back together - it works still. I have some basic pics, but at least they will help future fixers save themselves the $200-$600 depending on if they DIY or not.
My cost was $0. Time was over an hour all said and done.

I'd like to attach the pics - but don't know how. Can someone help?
Just post your pictures on any of the free places online that let you upload pictures (Picasa Web Albums, Facebook, Google for free picture upload and you'll find ton of hosting services. Once you have the pictures uploaded, use the
icon and paste in the link to the picture(s) you want to post.
I would like to see the pictures, since I plan to do the DIY fix first before buying a replacement part.
 

jonnyquest

New member
Joined
Jan 25, 2018
Location
Florida
TDI
2005.5 Jetta TDI 1.9L PD BRM
parts repair kit available

You can't buy "parts" because very few people are smart enough to figure out which "part" needs replacing. They wouldn't sell enough "parts" to make it worth creating a new stocking number and location.
I have a 2005.5 that gave Emissions Workshop! warning yesterday. Checked the code with OBD scanner and it was 2112. Researching fix and found this thread - thanks to all for the help and these posts.

While researching parts I did actually find a kit with just gears and seal for $42 on amazon called "Rebuild Replacement for Throttle Body Kit Compatible with VDO Siemens 03G128063 4E0145950 059128063 059145950, Part # X8R0170" (brand removed). Not trying to promote any product but thought anyone still reading this 2020 and on might like to know there is a cheaper alternative to replacing entire assembly.
 
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