purpose of long spring on throttle body linkage???

[ourv12]

On a 2.1 waterboxer I dont see the purpose of this long spring on the throttle body linkage.The throttle body has its own coil return spring which is more than sufficient to close the throttle. This long spring is attached to its own rotating bracket on the throttle linkage which seems to serve no purpose. Anybody know what its there for?

[tencentlife]

Take it off and you'll have your answer.

The mystery is why the coil spring and two-part pivoting assembly is there. It all serves no purpose I can decipher. But the long spring? That's what gets the throttle closed. Try running without it and see.

[ourv12]

If you hold the throttle body in your hand (off of the engine) and open and close the throttle by hand the coil spring closes the throttle not the long spring.The long spring attaches to the manifold and a seperate pivoting bracket which does nothing. Why is it there?

[Dogpilot]

I have always wondered myself. I think it is an evolutionary relic on the car, some kind of vistigial fuel sytem device, or a final fail safe, should spring 'A' break. Of couse if your from Kansas, it was put there in the flood.
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Geology with a Syncro rocks!
86 Syncro Westy AKA "The Bughunter"
98 Disco I
08 Range Rover SC
08 VW Rabbit S
1951 O-1G

[tencentlife]

[McVanagon]

Maybe the small spring is for the throttle, and the longer one is for the pedal and cable.

Together they happily work as a team to make sure when your foot says "no more" that the motor gets no more and you don't drive through the back of your garage.

How's that?
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'69 Mike
'85 GL
'87 Wolfsburg Hardtop

[Yellow Rabbit]

Is the spring the same on auto and manual transmission vehicles? Isn't there a kick down linkage somehow hooked to the throttle on an auto. Maybe the spring is different for that system.

I also like the theory that the extra long throttle cable needs extra spring force.

[Wildthings]

This would be a wild guess, but maybe it has something to do with allowing the throttle to open in case of a backfire. Some of the earlier VW products had problems in this area. That said I have always assumed that it was some king of relic maybe from an early cruise control?

[Terry Kay]

The spring is the same for a automatic or stick.

It's adds more pull to yank the cable back.

The coil spring on the throttle body isn't enough , especially when the cable of throttle linkage suffer's from pertrolis negletcus.

It's just a back up for the coil spring wound around the throttle shaft.
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T.K.

[slunk33]

I was trying to find a use for this spring as well. My spring looks like it has seen better days. There was hardly any resistance, and the spring did nothing to pull back that little lever on the top of my throttle body.

I have been having a surging issue since I purchased Clark last Thursday. My first thought was a vacuum leak, I check the engine compartment and noticed the purple vacuum hose was unplugged from the throttle body. I plugged it in, but my idle did not change. I began reading my Bentley and tried many of the fixes in there as well as many of the fixes on here. When I tried for find a use for this spring, the only evidence I could find of it were drawings of it on top of the throttle body in the section concerning adjusting the TBS. The lever the spring pulls on was pointing towards the front of the engine compartment, whereas in the pictures in Bentley, the lever is pointing left. I attempted to adjust the throttle body switch, but my idle only got worse, and I thought I figured it out when I did not hear the switch "click" when I depressed the throttle off idle. After I adjusted it to where I could hear it "click," my idle got terrible. Clark just stumbles when he is cold and will even die. I attempt to give him gas and he just sputters. I can't tell if its a too lean or too rich problem. After he warms up, he performs fine.

Anyway, I decided to look at this spring again. I discovered it was worn out. I cut back a couple of the rings to give it more tension. The lever now pulls the throttle cable taunt against the throttle body. I'm thinking my adjustments to the TBS were in vain, because the van was not at a true idle position. I am excited to get home tonight after work and adjust the TBS again to see if I can smooth out Clark's cold idle. I did notice the accelerator pedal was more solid, gave the van a newer feeling. I will post what I find out tonight. Anyone else have this type of issue with that spring and not being able to adjust the TBS correctly?
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Current VW's:
'70 Standard Beetle Convertible, '89 Vanagon Wolfsburg (Bluestar) "Gonzo", Peg-Perego Magica

Former VW's:
'72 Bus, '75 Bus, '78 Sunroof Bus, '87 Vanagon GL, '00 Jetta TDI (Gas companies don't miss her, but I do), '04 Passat Wagon

[slunk33]

Hurray!!! I have fixed the idle!! The problem I was having was with that damn long spring... My throttle body could not click back to idle after applying fuel. Like I said in my previous post, I cut the spring down to give it more resistance. Well, after having to take the throttle body off to properly adjust the idle stop screw. I reassembled, and readjusted the throttle body switch. This is when I realized the switch was not switching back to idle after I opened the throttle. I made the spring tighter, but I think I will need to replace it altogether. Off to the Home Depot today...

After I got a smooth idle, I adjusted it down and at that time the oxygen sensor kicked in and messed up my idle. I turned off the van, disconnected the sensor and was able to completely adjust my idle. I will leave the oxygen sensor disconnected until I get a replacement.
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Current VW's:
'70 Standard Beetle Convertible, '89 Vanagon Wolfsburg (Bluestar) "Gonzo", Peg-Perego Magica

Former VW's:
'72 Bus, '75 Bus, '78 Sunroof Bus, '87 Vanagon GL, '00 Jetta TDI (Gas companies don't miss her, but I do), '04 Passat Wagon

[brooklynvanagon]

maybe it's to even out the wear... so that the bearing doesn't wear only in one direction.

[piruvan]

I'm missing that long spring altogether. Does anyone sell it? Find one at a junkyard maybe? Or substitute with any spring that'll work? Been running without it and my idle has been OK but a little slow to come down at stops.
I've also got a worn throttle body and broken TPS switch. It's a wonder my van idles at all.

Yeah, I need to fix up the old TB.
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'89 Vanagon GL "Whitestar" Wolfsburg edition. 4-speed, 2.1L
'06 Accord EX-L 5-speed

[Captain Pike]

Imagine how many times that spring has flexed
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LEARN TO SELF RESCUE
59 Panel bus, 1966 Single cab. 73' 181. 73 Westy. 91' H6 Vanagon 3.3L.
....Bad Sneakers....

[Ahwahnee]

I would think a generic spring could be substituted but would sure help of you had an examle to compare to what's available.

As I recall, in racing circles thottle returns are not allowed to rely on justone spring. Okay, not too many of us racing our Vans but redundancy may be part of the thinking.

[tencentlife]

The national FLAPS sell long springs in their generic parts sections that are easily adapted to work here. A fresh spring is a good way to go, the OEM spring does get tired after all the years of stretching, but you can also get more life out of the existing spring by shortening the wire extension a bit, try about 3/8" at a time.
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[SteelB12]

Might anyone have the length of this spring handy. I have noticed that my van is lacking it.
Just to be sure, we are talking about the spring that is attached on the engine itself. It is the spring between B and D in this photo from Ben's site
http://www.benplace.com/fi_hoses/100_0002.jpg

I figure my local ACE might have something. They always have hardware I can use on my bikes.

Thanks
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1987 Westy

[Wildthings]