In the process of removing my broken plastic radiator, I found this tubing line with a open nipple and a small ring of tubing residue surrounding it. The line comes from an electrical module on the left and runs to a brass nipple under the throttle body or the right. It apparently supplies vacuum or air to something since there wasn't any liquid present. When viewing the pic, the nipple is visible just above the thermostat housing neck. The nipple didn't have a hose connected to it so I question its purpose other than leaking air!! Did a previous mechanic forget to connect this to something? I am puzzled and hope someone can provide an answer. Thanks, Gregg

don't know anything about 840's but it looks to be part of the fuel / tank venting system.

That nipple was one of the causes of my Trans Fail Safe trigger. It caused a vacuum leak since the cap was broken (along with the rotten IM gaskets and worn-out PVC valve).

Ironically, I actually think the purpose of the nozzle is used to introduce smoke from a smoke machine to check for vacuum leaks!

Here's an old post with pics that I took:

http://forums.roadfly.com/forums/bmw/bmw-8-series-e31/8614834-1.html

Koizumi,
Just trying to clarify your answer. Do you mean that the nipple should have a cap on it? If that is the case, why the nipple in the first place? Are you suggesting that the nipple isn't connected to anything? My nipple had a small ring of rotten rubber around it. What should I order as a replacement? What is the purpose of the electric module one end of the hose is attached to? Why is the other end fitted to a brass nozzle beneath the throttle body?

To be honest, I don't conclusively know what the purpose of the nipple is. My mechanic & I theorized what the function of the nipple is. It is supposed to have a cap. Mine did, but it was rotten and had a tear in it. I replaced the cap with a random rubber cap from some other car that happened to be laying around at my buddy's shop. It fit perfectly, so it worked out. I have no idea what part# the replacement is. In fact, we could not find it in the ETK at all. I can tell you that when we finished replacing the the IM gaskets, PCV valve and valve covers, we started the car with the nipple cover off... And the car hyperventilated. We put the cap back on the nipple and the car stopped hyperventilating. This was confirmed with a smoke machine test, too. So the capless nipple is indeed a possible breach that does cause a vacuum leak. I would put a cap on it. If anything, it's easy to do, provided that you can find a cap that fits appropriately.

It would be nice to definitively find out what the purpose of the nipple is. It could be that the nipple assembly is part of another engine type; but that the M60/62 just happens to use the same general parts as some other BMW engine? Just a thought. I mention this since the V8 E31 shares some parts from V12. For example, the massive dual intakes are rerouted to one entry point for the V8. But upon close examination, you can see that there is a removable cap that is used for dual intake hook-up with the V12. This is just an example of common parts btwn the V8 & V12 E31.

In the end, there remains very little information about the M60/62 engines in respects to their application to E31. This is unfortunate. Sure, we can scour other BMW platforms that use the M60 & M62 but in the end, it is not entirely the same when it comes to certain specific E31 details. This is why I've always attempted to post pics and procedures online to add information to the public domain.

Cheers

Whale,

I'm at work bro so I can't really check too much ... but is it this one?

http://forums.bimmerforums.com/forum/showthread.php?t=905214

Yo,
Rod

It appears to be... I stupidly posted this info in the wrong thread.


Thanks Rod for reminding us!

Part# 11611727176 $0.75


Number 7 below:


http://img166.imageshack.us/img166/80/capaq8.png (http://imageshack.us)

You guys are great! Item #7 "cap" solves my deliemma. I guess, like many, my cap was just rotted off for some reason. I am curious how that would happen when the rest of my hoses are like new! Like one suggested, to prevent this happening again, I might just eliminate the nipple fitting and replace it with a longer hose from the module to the throttle body.