A PO at some point in history removed the air pump from my car.

But what do I do to the remains? What hoses to remove and blank off?

What I have now is 18, and everything behind it. (21, 23 e.g.). 16, 7 and 1 are all gone.

I would like to rip out any non-functional items, but also make sure I create no air leaks.

MM

 

Take all away and replace both 32's with plug is option one.

Option two is to leave 27 and everything beyond that, remove 24 and everything before that. 25 is one way valve that prevent exhaust entering into pump. It opens when pump produces larger pressure than engine. Block hole on 25 to prevent stuff going in or take 25 away and block entry hole to 27.

 

where does 22 go?

 

I think 22 goes to the port set on the back of the throttle body. Just plug it.

I removed all of it except for the pump itself. That is gutted and simply serves to tension the fan belt.

The correct replacement plugs for 32 are the same plugs as used for the port on front of the heads. I tried to source and then fab one locally before realizing it could be purchased by P/N from your friendly Porsche authorized dealer or re-seller: 900 219 004 02 for the plug and 900 123 018 30 for the sealing ring.

 

The problem with leaving the pump on is that there's some drag from it. You can get #7a from Jim sometimes but it's not cheap. You can also get a 21" belt and just go direct from the crank pulley to the fan, which is what many of us have done on pre-S4 cars. Unlike other cars, this belt only drives the fan, and not the water pump, so there's little drag to concern yourself about a tensioner. Loosen the fan mounting casting from the engine block to install the short belt.

Block off the vacuum line at #21, and cap the fitting at 31 and it's all good. I made a plug fit into the end-fitting of #28 to make the termination.

 

I forgot #22. Plug it as others have stated. It's possible to minimize pump drag by taking some of the internals out. Replacing bearings and blocking input and output holes at same time makes sure pump will work as belt tensioner for years. Probably longer than #7a as bearings are further apart in #7.

 

Brian,

With the vanes removed it's not taking any more power than the tensioner would. Spins easily. I've chosen not to use the short belt. It'll be too tight or too loose (with my luck!) and what I've got is working well.

 

26 looks like a T-piece. Plugging 32 would leave an opening to where 25 normally goes. Or?

But plugging the "north" 32 would make it possible to delete teh second 32. Or?

And 23 goes where? The main air filter?

 

Yep, 23 goes to the air box as an exhaust for excess air. I've plugged that but think it was unneccessary. It keeps hot air from being sucked in. Likely not a big deal.

 

I had a Gates 20" I think on there. It fit perfectly.

Re: gutted pump. Even with little drag there is the issue of the pump bearings. We're splitting hairs here, but if you aren't using the pump, I would bypass the pulley. Eventually you will be replacing those bearings, Or maybe not. and IIRC, unless you remove the tensioner it is a bitch getting the pump in/out.

 

16mm oil drain plugs work too.

...

Note that CIS engines without O2 sensor have the air injection into the head, which exits at the exhaust valve. This is meant to oxidise any unburnt gas.

L-Jet uses the same port on the head, but it is drilled into the intake port instead, for the cold-start idle speedup. Air injection goes to the rear of the cats (except 80, with no air pump).

 

I did the same thing as GlenL. I gutted the pump and reinstalled it as a tensioner. I did not plug or block any thing and have not noticed any problems as of yet. PO removed the cat.

 

On my S4 I removed everything; plugged the hole in the air filter housing and the vac line to the diverter.

All the pump, diverter, hoses, cats etc etc is on the shelf................I should weigh it all one day to realise the improved HP gain!

 

It's certainly easier with the S4 since you don't have the rad cooling fan to drive. I did exactly this with my S4.

On my '86 car I found that the shaft bearings were shot on the AIR pump. The rebuild wasn't worth the time or effort or $$$ since the short belt was so easy and effective.

YMMV

 

I suggest you remove everything and use the correct plugs in the heads, that's what I have done. The air filter canister was VERY awkward to remove, there is no way that thing is going back on my car...