TheSamba.com :: View topic - What is this part and is it needed and which way does it go?

Tue Nov 11, 2025 5:55 pm

Hi all,
As part of me fighting some idle issues and taking apart things that connect to the throttle body I am wondering that part 27 is in the attached image. It appears to be a sensor but in trying to google the part, I couldn't find it. GoWesty also doesn't have it(according to the schematic parts list). I cleaned it with carb cleaner as it looked pretty basic. Does anyone know what it is and if it's available or is it needed or not? Finally...if it's needed and just ok to carb clean(if not available)....do you know which way it attaches to the boot? Is it long barb-side into the boot or long barb side into the hose from the breather tower? Thanks in advance...

Tue Nov 11, 2025 6:27 pm

It's a heating element and also a restrictor for the crankcase vent to the intake. If you are in a warm climate, you could probably due without it. But, you may still need some sort of restrictor.

Hans

Wed Nov 12, 2025 8:21 am

Early vans (e.g. my '84) didn't have that part, just a simple hose.

I added a restriction to mine (no heating element) to improve idling behavior.

A simple plumbing part drilled with a suitable aperture (5mm?) was all it took.

Wed Nov 12, 2025 8:29 am

From a prior post on a similar thread...

Ahwahnee wrote: I did have a idle issue at one time -- it would tend to 'hunt' or 'surge' at idle. I did many things, diagnostic, adjusting and parts swapping in search of a smooth idle and better mileage so I cannot say for 100% sure which changes smoothed the idle but I think I know what had the biggest effect.

On the 84 the hose from the breather tower to the S-Boot is just a plain hose. At some point VW added a device midway in that hose that (I think) had a heating element to prevent icing and also a restriction to reduce flow.

I duplicated the restriction by inserting a plug into the hose with a 5mm diameter opening drilled thru it.

The plug (hole not yet drilled):

The UPC label from Ace Hardware:

The threaded end of the plug I inserted into the exit fitting on the breather tower, then slipped the hose over it.

Of course, if 85s came with a restriction already in place (I have no idea) then this is not going to help you.

The clue that suggested to me that reducing the flow there might help was that when the idle was surging, removing the oil filler cap would greatly improve it.

Wed Nov 12, 2025 10:52 am

Thanks all for the input! I cleaned up mine and will just leave it in as it sounds like it helps idle.

Wed Nov 12, 2025 11:40 am

Ahwahnee, that’s great!

Have a fast idle issue, now that I fixed a vacuum leak I found last week.

I was considering something very similar… but a short, nested group of spare 1- to 2-inch-long hoses, siliconed together, that I could add or remove to get the best running. Goal is the siliconed cluster having zero chance of getting sucked in (!), maybe with a long and thin screw going right into the breather-to-intake hose.

Never tried this but am confident this will help control idle (have no stabilizer installed right now…). I suspect too much unmetered air.

Wed Nov 12, 2025 4:58 pm

I went ahead and pulled my throttle body after fussing with other stuff and found the inside of the body had quite a bit of "rubbing" on it from the butterfly. I'm sure that must be it as nothing else worked so I ordered a new one. My van has been running like a top since I originally went through it so I don't feel so bad spending for that part. Ran fine until it got colder so guessing the cold air must cause the TB/butterfly to "stick" a little or let more air through until things warm up quite a bit.