DIY: Intake Manifold Spacers + SAI Delete + Throttle Body Heater Bypass

B6 A4
#1

This thread will detail my install process and tips for installing the JHM intake manifold spacers. For those that don’t know, the intake manifold spacers act as a barrier between the intake manifold and the help reduce intake manifold heat-soak. Testing has shown a difference of up to 40F.

The Secondary Air Injection system is some silly emissions system that is unnecessary. It will only ever be used to inject additional air into the exhaust system during cold startups. It is safe to delete and JHM can modify your ECU to ignore the codes that will be produced when the system is blocked off. This is completely optional, but I’d recommend to go ahead and do it if you have the appropriate tune.

The throttle body has two small coolant hoses connected to it to allow coolant to flow through it. The purpose is to give additional heat to the throttle body, which is really only useful in cold climates. In warm climates we need to keep as much heat out of the throttle body as possible. Originally I didn’t plan to do this mod, but when I broke off one of the coolant stems at the main coolant pipe it presented the opportunity. An audi mechanic I know said that I might have trouble with idling if I bypassed the TB heater hoses, but I haven’t had a single problem since I did this mod.

Tools needed:
Phillips screwdriver
Flathead screwdriver
Ratchet
10mm socket
Metric hex sockets(I’ll post exact sizes later)
Wobble socket extensions(might be able to get by with regular socket extensions)
Vice grips or hex key needed to remove one of the SAI pipe bolts
Long needle nosed plyers(most valuable tool on this job - because f*** Audi’s hose clamps)
Channel locks(optional - I found it was the easiest way to take off the hose clamps on the air duct accordion tube)
Pry bar(optional)

Supplies needed:
3/4" electric pvc cap(for SAI cap-off)
silicone adhesive/sealant(for SAI cap-off)
2 packs of vacuum tube caps from autozone(for throttle body heater bypass)
2 small hose clamps(for throttle body heater bypass)
2 large hose clamps(optional, but it’s a great idea to replace the hose clamps on the air duct accordion tube)

Disconnect the ground cable from the battery(safety first lol)

Remove your engine covers

Remove air duct

Remove air filter housing

Remove MAF tube and accordion hose

Now is a good time to seal off your air filter housing aka Zingo’s mod if you haven’t done it yet.

Disconnect vacuum hoses, electrical connector, free up crankcase accordion vent hose, and remove screws from solenoid valve retaining plate. It’s a good idea to take a picture of what it looks like before hand so you know how to reconnect everything. BE GENTLE with that accordion hose, it was very brittle on my car with about 70k miles and snapped very easily.

Disconnect highlighted vacuum hose and electrical connector:

Time to pull out the fuel rail and injectors! Bentley manual says to disconnect the electrical harness connectors at the fuel injectors first. I actually found it much easier to pull the fuel rail up first.
Remove the 4 hex head bolts securing the fuel rail.
(If you have a 2002-2003 car)Disconnect the fuel pressure regulator, which is kind of at the back/right corner of the fuel rail.
Use a pry bar or something similar and slowly/gently apply upward pressure to the middle of the fuel rail on one side until the fuel injectors pop out. Repeat on other side.
Now you have plenty of room to disconnect the wiring harness clips.
Once disconnected, flip it over to the left side of the engine bay and cover the fuel injectors with clean rags.

http://i.imgur.com/E0Kzu.jpg

Clean the fuel injectors up before reinstallation.

Above throttle body, disconnect electrical connection to throttle valve control module(1), and vacuum hoses 2 and 3.

Disconnect resonator hose(1) from air duct. Back out the screw(4) securing the air duct to the throttle body and remove air duct. If equipped, disconnect the vacuum hose(3) from air duct.

http://i.imgur.com/M5HYz.png

Now is a good time to go ahead and cap off that resonator connector on the air duct if you haven’t already done it.

Remove the two screws securing the oil dipstick tube(1 and 3) If you plan to remove the SAI pipe, disconnect the plastic accordion hose from the end of the SAI pipe.

http://i.imgur.com/EDf1s.png

Remove the two bolts securing the SAI pipe. The left bolt in the picture has tought clearance. I grabbed my hex socket with a pair of vice grips. You might want to use a hex key.

http://i.imgur.com/2ltwb.png

Remove bolts securing the SAI pipe(1 and 2). Remove bolts securing the resonator(3,4,5) and remove resonator. Don’t reinstall the resonator if you plan on sealing the air duct.

http://i.imgur.com/SCVp2.png

You can go ahead and remove the SAI pipe if you choose to. You’ll want to disconnect the left cylinder head vent tube for clearance and then pry the SAI pipe out of the hose it connects to.

http://i.imgur.com/DD2UF.jpg

Wiggle the SAI pipe out however you figure. I pulled it towards the front of the car and turned it some kind of way. Should look like this when you’re done:

http://i.imgur.com/DBdq7.jpg

Get that 3/4" electric pvc cap(I got mine from Lowes), smear a bit of silicone adhesive sealant around the inside and smash it on that rubber tube. Should look like this when you’re done:

http://i.imgur.com/RAzn6.jpg

This might be different on some cars depending on model year, but on my 2005 BGN motor I had two coolant hoses and two vacuum hoses connecting to the throttle body. The vacuum hoses are fairly easy to disconnect from the throttle body side using long needle nose plyers. Use your long needle nose plyers and make sure the hose clamps on the coolant hoses are fully open before attempting to disconnect them. The stems that extend from the main coolant pipe might be weakened and can snap with little force.

Inspect the spaces around your intake manifold for dirt and grime and vacuum or blow out any that exists. You don’t want that stuff getting into your intake ports.

Remove the 12 bolts securing the intake manifold to the cylinder head and remove intake manifold.

http://i.imgur.com/KQkyr.png

Plug the intake ports with clean rags or rubber gloves while you finish up your other work, sealing the air box/air duct.

If you choose to bypass the throttle body heater:
Get those vacuum hose caps and cap off the two small stems extending from the main coolant pipe. I would use hose clamps on these since there will be some pressure exerted upon them and we don’t want coolant going everywhere. See picture below, blue highlight is where one of the stems used to be until I snapped it. Go ahead and cap off the coolant hose stems on the throttle body side too. You don’t need any additional security, but I zip tied them anyway since I like zip ties.

http://i.imgur.com/XxtVx.jpg

Before reassembly, take time to inspect your intake ports for carbon buildup or any debris that might have fallen in. I had a thin coat of oil around the top half of the intake ports and I was able to clean it off using my fingers. Also go ahead and clean up your intake manifold and fuel injectors.

Go ahead and put your spacers and gaskets on. The gaskets go under the spacers. Other than that they can only fit one way - make sure the bolt holes all match the holes in the spacers/gaskets. The spacers/gaskets will move around a bit when you put the intake manifold back on. I use a 1/4" ratchet extension to insert through the IM bolt holes and maneuver the spacers/gaskets until they were lined up proper.

Put everything back together. Intake manifold bolts get 10Nm or 7.5 lbs. Tighten in a diagonal pattern in stages. I did 7Nm on the first pass then 10Nm on the second pass.

Congrats! You now have a more efficient motor!

Let me know if you have any questions.

#2

Oh yeah, some pics of my airbox/air duct mod. This was my first time using plastidip, and I used the spray. Looks junky, but good enough for me.


http://i.imgur.com/bd8eB.jpg


http://i.imgur.com/ZKr0E.jpg

#3

very nice writeup, solid work

#4

X2, great write up!

#5

Great write up Komesh, I might have to squeeze this in when I get my spacers in next week. How long of a job would you say it is?

And you still up for those beers in a few weeks?

#6

It might add 30-60 minutes to the job since it’s pretty much a “while you’re in there” thing. The stuff you need to take off to remove the intake manifold makes the coolant pipes and SAI pipe accessible.

Definitely up for the beers. Let’s exchange contact info via pm at some point.

#7

Alright good deal, just wanted to make sure I’ll have enough time. Get the spacers Wednesday, birthday is on Thursday, leaving for Fixxfest Friday. So busy busy lol

What are the benefits from deleting such lines and capping them?

#8

SAI you are getting an unnecessary emissions component out of the engine bay. A little bird also mentioned that SAI removal might be required if JHM throws a supercharger kit our way.

For the throttle body heater bypass you are preventing engine coolant from flowing through the throttle body, thus keeping it cooler.

#9

Alright cool, great info. I will probably tackle this as I’ll be there anyway.

I can’t access anyone’s profile so I can’t send a pm, maybe you can send one to me? Lol

#10

you used the 2.7tt/2.8 30v spacers from 034?

http://www.google.com/url?sa=t&rct=j&q=jhm%2030v%20intake%20manifold%20spacers&source=web&cd=1&ved=0CCYQFjAA&url=http%3A%2F%2Fjhmotorsports.com%2Fshop%2Fcatalog%2Fintake-manifold-spacer-034-motorsport-5mm-thickphenolic-30v-p-92.html&ei=Sy67TuqsCuLq0gGT4qHfCQ&usg=AFQjCNFMjuz6gGfFTcAV8QHgjKA6d1wnNA

did you leave the little white plastic guides in the head for the intake manifold?

#11

They are the intake spacers from JHM.

#12

Updated with intake manifold bolt torque and tightening instruction at bottom of first post:

Intake manifold bolts get 10Nm or 7.5 lbs. Tighten in a diagonal pattern in stages. I did 7Nm on the first pass then 10Nm on the second pass.

#13

^ just curious, do you actually have a torque wench that does NM that low? The only ones I’ve ever seen are quite expensive, but wouldn’t mind having something for doing certain jobs like VCG etc.

Also, maybe it’s b/c I’m familiar with the S4 engine bay more. . . but it almost looks like more crap you’ve got to move out of the way to do this then on the S4 (The one thing on the S4 is you kind need to put it into service position for more room up front, i.e. move the lock carrier forward 2-3 inches. I’ve done it without doing that, but my hands paid for it and probably didn’t save any time). Great post, I’ve done this enough on my car that I don’t even look at the directions anymore lol. . sad.

#14

Yeah I picked up a few of the high dollar snapon digital torque wrenches. I use them so often for my e30 track car project it ends up saving me a lot of time. The 3/8" drive goes from 5-100 ft-lbs and the 1/2" drive goes 25-250 ft-lbs. I’m pretty sure harbor freight has torque wrenches that go that low. I know for sure that craftsman does.

Since the intake resonator is permanently removed now this job will be a good bit easier/quicker in the future.

#15

Unless I choice read, I didnt see anything about draining anything at all? If that is the case that would be awesome, but if no, did you have to drain anything to get the job done?
I’m looking at doing this tomorrow as my spacers will be in

#16

You will have some coolant leaking out when you disconnect the throttle body warming coolant lines. I would be ready with the vacuum caps and quickly plug em after you disconnect. According to JHM they lost about a cup of coolant without plugging the line.

I’ll update the original post.

#17

Alright good deal, just got a notification that my spacers are in so maybe I will get on that today if my car is done

#18

Can someone please confirm if the tune is needed to do the SAI delete? Mine just crapped on me so I’d like to remove it.

#19

You might already have it if you have the JHM tune. If not they are going to need to update it for you… the Sai system can’t be tricked

#20

No, I don’t have the tune yet. I’m just considering the cost of a new secondary injection pump if thats the case, could just be a hose. But I figured 400$ or whatever they cost new I might as well buy the tune and delete it.