SAI / 249 Bypass - guide

[noone]

There are a few threads on this, but thought I'd put something together to explain.

Going to need to do this with borrowed photos, etc.

------------------------------------------------

What is it? Removal of the Secondry Air system on the Polo GTI (may suit other vehicles).

Why: The pump / combi valve is prone to failiure and the Vac system is not required (IMO) after the SAI is removed:
The Vac system includes N249 control which allows the ECU to modify the boost slightly
The 249 also regulates the VAC to the diverter valve, for tuned Polos, some have found more consistant boost or better diverter action (noise) from bypassing.

Downside: As I understand (so not necessarily correct) The SAI system is designed to reduce emissions by heating up the CAT faster

What is required:

For my car (should suit Polo 9N3's as a whole, but don't quote me on that) best results have been experinced with the following parts:
2 x IE Oval shaped Resistor Plug (http://www.intengineering.com/integrated-engineering-sai-evap-delete-resistor-oval-plug.html)
1 x IE Resistor (http://www.intengineering.com/1-8t-sai-pump-resistor.html) (they cost very little I'd get 2, just in case)
IE SAI blanking plate (http://www.intengineering.com/1-8t-sai-blockoff-plate.html) There are a few places to get these

As postage is significant, group buys are prob the best way to go.

-------------------------------

Asside from the above, you are likely to need a few bits and peices that can be locally sourced or may be in your stock of car crap;
- Top up of G12++ coolant as some is lost in the process (volume TBC based on Jmac's help of how not to loose a lot)
- 1 meter of vac line (as its cheap, get more). I think 3mm or 4mm is what suits, you can cut off 1cm from your existing vac lines and take it in to a auto store to see what is suitable. You are better off with forcing on something to small rather than larger, looser fitting piping.
- A few decent small cable ties
- Basic Hex / security bit set and tools (I have a mini ratchet set I use frequently).

Overview;
So again, I have to apologise for borrowing someone elses photo for this. If I've used a photo of yours and you don't want me to, please let me know and I'll take it down.

Once the engine cover is off, your engine looks something like this;
http://www.vwwatercooled.com.au/forums/images/imported/2012/09/Guide1-1.jpg
1 The SAI Sensor electrical socket - use one resistor plug
2 The VAC resoervoir system, junk and bracket (held on with 3 bolts, small socket set to remove)
3 N249 system and electrical connection - bypass this
4 Diverter Valve - connect vac line to manifold
5 Combi Valve - this is to be removed when the bolts attaching it to the engine are removed

A few reference photos from when i did this originally (threw codes, so put it back)

the removed parts:
http://www.vwwatercooled.com.au/forums/images/imported/2010/09/removed-1.jpg

Small blanking plate I cut from plastic and taped over the stock airbox hole
http://www.vwwatercooled.com.au/forums/images/imported/2010/09/airbox-1.jpg

Procedure:

Remove the vac lines:
- From the intake manifold to the VAC / 249 System
- From the N249 to the dverter
- From the vac system to the combi valve

- Run a new vac line direct from the manifold to the diverter. you should also have another line from the mani to the FPR still.

Disconnect the 2 electrical connections (Vac at #1, N249 at #3).

Remove the 3 bolts that mount the SAI system onto the top of the engine block.

The SAI system should lift loose, ready for storage / bin.
Use the 2 oval resistors in the SAI and N249 electrical plugs.

Thats part 1 done.

Part 2 I'll try and get some more photos for.

Disconnect the 2 flex hoses that run to the combi valve and Airbox.
Plug the airbox hole (I cut a circle from thick plastic and used tape and a cable tie to keep in place)
The SAI pump is located in front of the intake mainfold. The bracket that the dipstick clips into holds the SAI pump in place.

Disconnect the SAI pump electrical plug and tock airbox pipe / PD160.

The pump is held in by 3 bolts, one where the dipstick mounts and 2 through the top of the mainfold. they form a triangle.

Remove these 3 bolts, whilst supporting the pump. The bolt nearest the dipstick mounts a seperate bracket on, mind you don't drop this.

The pump should lift out towards the battery.

Use the bare resistor in the end of the pump's electrical connection (I again used electrical tape and a cable tie to secure).

The last part is removing the Combi valve, this bit requires good access to the side of the engine, removing the flex pipes for the pump has helped with access / visibility.

In order to access the 3 bolts at the bottom of the combi, a coolant pipe (well, 3 that join at the side of the block) needs to be removed. If you remove the coolant pipes, you loose a large amount of coolant. I'm hoping to be able to clamp the 3 pipes around this and not loose all my fluids.

[Mr Blobby]

Very interested in this, and there are no disadvantages other than not warming the cat up as quickly?
Just wondering what do you guys here use to check your engine codes? Because on the other thread about the SAI delete some of you were saying how you logged your boost and things like that, I can borrow my friends VAG reader for codes but thats all it does and i want to do more than just read codes...

[noone]

The big disadvantage IMO is possibly throwing a code. I dont like having a CEL warning on my dash. This solution seems to work.

Once a few other bits arrive (need allan key style bits for easier access), I'll finish it off.

[dubstar]

Can you just remove the SAI and Combi Valve? Leaving the N249 in place?

[VWindahouse]

The big disadvantage IMO is possibly throwing a code. I dont like having a CEL warning on my dash. This solution seems to work.

Once a few other bits arrive (need allan key style bits for easier access), I'll finish it off.

Hey mate in regards to the CEL, I remember now what I did to erase the issue once and for all. I threw a code at about 500kms after the delete because I stupidly bought 1 oval and 1 square resistor so had to go to Jaycar to get one of the bare resistors (like the one IE sell for the SAI pump) to go on while I waited for a another round one.

He didn't have a 330 ohm resister so he piggybacked 2 smaller ones which gave a total resistance of about 400 ohms from memory (or maybe a little less) anyway it seems 330 is too little and will through a code. But a bit more resistance does the trick and I have not had a CEL for over 15,000kms :eek:

[VWindahouse]

PS great write up!

[s4mmie]

If you want to get rid of the vac reservoir and N249 to free up a little space in between doing the full delete you can.
All I've got on top now is the N112 still connected, waiting on INA for my flipping resistors! :facepalm:

[Redliner]

Thanks noone.
The pics help heaps.:raiseroof:

[Catfish]

I took a different approach - removed the combi valve and blocked off the top of the tower. A bit easier and no coolant loss.

http://www.vwwatercooled.com.au/forums/images/imported/2012/09/4a15c048-1.jpg

http://www.vwwatercooled.com.au/forums/images/imported/2012/09/d43ef885-1.jpg

[noone]

Looks good too, thanks.

[Mr Blobby]

Thanks for this guide, I didnt even know you could get rid of all this crap, it makes the engine look so much better and easier to work on :)
Which one is the N112? Is it the one as number 6 in the diagramme?

[Stuwey]

For my car (should suit Polo 9N3's as a whole, but don't quote me on that) best results have been experinced with the following parts:
2 x IE Oval shaped Resistor Plug (http://www.intengineering.com/integrated-engineering-sai-evap-delete-resistor-oval-plug.html)
1 x IE Resistor (http://www.intengineering.com/1-8t-sai-pump-resistor.html) (they cost very little I'd get 2, just in case)
IE SAI blanking plate (http://www.intengineering.com/1-8t-sai-blockoff-plate.html) There are a few places to get these


Their site says

"Which resistors do I need?

For a 1.8T:

N80 valve (EVAP purge valve) - oval style

N112 valve (SAI combi valve) - rectangle style

N75, N249, VVT - rectangle style"

? Does that not mean

1x Integrated Engineering EVAP Delete Resistor (Oval plug) (http://www.intengineering.com/integrated-engineering-sai-evap-delete-resistor-oval-plug.html)

and then

2x Integrated Engineering SAI/EVAP Delete Resistor (Rectangle plug) (http://www.intengineering.com/integrated-engineering-sai-evap-delete-resistor-rectangle-plug.html)

??

I'm lost. Again.:facepalm:

[VWindahouse]

Polo's need 2 x Integrated Engineering EVAP Delete Resistor (Oval plug)

1 x 1.8t SAI Pump Resistor (http://www.intengineering.com/1-8t-sai-pump-resistor.html)

1 x Blanking plate

Plus read what I said earlier regarding CEL's

Cheers.

[Catfish]

Which one is the N112? Is it the one as number 6 in the diagramme?

It's at 1 in the first photo.

[noone]

Well, CEL came on today... have to scan it, but I'm guessing its the incorrect flow message.

Cant figure why, but the cars that seem to have success with this are not running APR?

Wonder if it would be easy for Guy to code it out...

[clicht]

Well, CEL came on today... have to scan it, but I'm guessing its the incorrect flow message.

Cant figure why, but the cars that seem to have success with this are not running APR?

Wonder if it would be easy for Guy to code it out...

haha, it had to happen....
Mine came on about 4 weeks ago
Let me know if Guy contacts you.

[s4mmie]

I've been thinking this too.. surely Guy could code it out.
I think Revo/Unitronic(?) code it out of theirs...

[Catfish]

Well, CEL came on today...

Same here. Could it be the 300 ohm SAI pump resistor from IE (the bare one) is inadequate, as suggested above? Should we try a 10W x 350 or 400 ohms (both on ebay) and see what happens.

Whatya think?

[leitch]

I am now running two resistors in series from Jaycar totalling about 650ohm from memories and haven't had the CEL return. I think the one specced by IE is just not enough by itself.

[noone]

Given the code is for flow, I assume it's to do with that...

[Paulbag]

Great tutorial!

Any other vacuums which can be removed?

[s4mmie]

Would disconnecting and capping the SAI, combi valve, n249 and n112 but leaving them in place be ok? I figure it would be the same as resistoring them out, they're just still there.. I've done this and the missers just threw a CEL this morning. I haven't had a chance to read it yet but I presume it should just be for the incorrect flow?

[noone]

yeah, I've not found a solution on my car. Throws a cell.

If anyone has thrown this cell and can do a scan (Vag-com), ot would be valuable to send through to Guy (then they can investigate coding out).

I've been meaning to do this, but have recently changed to Win 7 64bit machine and it does not like me anymore...

The only reliable solution I know of is coding out, others are hit / miss depending on tune, etc.

[h100vw]

Would disconnecting and capping the SAI, combi valve, n249 and n112 but leaving them in place be ok? I figure it would be the same as resistoring them out, they're just still there.. I've done this and the missers just threw a CEL this morning. I haven't had a chance to read it yet but I presume it should just be for the incorrect flow?

Did that on the S3 Sam, although I pulled the air pump off for better access to the oil filter. The 249 is out of circuit and the 112 is linked out. You can have a look at the weekend if you like.

Gavin

[clicht]

When I changed my battery, it cleared the CEL...been a while, and no CEL haha

[s4mmie]

Thanks Gav, i'll have a peek.

I was giving it a bit of thought.. how is the flow measured? The problem comes from 'insufficient flow' detected. What's detecting it?
I'm not great with electrical but I assume the pump draws a specific amount when pumping air through.. is it the electrical draw that's measured? I don't think that's how it works as I still have the pump pumping away and it still throws a code..

The only other thing I can think is that the ECU is hard programmed to expect more air on cold-starts.. in that case no combination of resistors will fix that. Saying that, others are fine, no CEL's. Bah!

[s4mmie]

Anyone had any trouble bleeding the air from the coolant once it's topped up? I've just finished the deleting the combi valve and I can't get any got air from my heater... seems like it hasn't bled properly. Is there a bleeding point other than the coolant ball?

[h100vw]

Anyone had any trouble bleeding the air from the coolant once it's topped up? I've just finished the deleting the combi valve and I can't get any got air from my heater... seems like it hasn't bled properly. Is there a bleeding point other than the coolant ball?

That Polo I just got was the same, You need to drive it a little I reckon. Then let it cool before topping up.

I just revved the engine in the garage and topped up an hour later but I think a drive would be better.

Gavin

[s4mmie]

Yep all good now. Thanks Gav. I thought as much, but you never can trust these Germans... ;)
Zere ist bleeda screwz vich are hidden in many locations und must be undone or zee hole zing go boom!

In keeping with this thread I noticed a few other lines..
There's a line that comes from the inlet manifold and splits off into a Y piece. One then goes to the brake booster. The other goes to the TIP with what looks like a one way valve. What's the point of this valve? Can I just run a hose straight to the brake booster and get rid of the Y piece and one way valve in the TIP. I'm trying to get rid of a couple of hard lines messing up the place.

They can be seen here --

http://www.vwwatercooled.com.au/forums/images/imported/2012/10/IMG_0527-1.jpg

http://www.vwwatercooled.com.au/forums/images/imported/2012/10/IMG_0528-1.jpg

[kaanage]

To maintain the brake booster vacuum when the diverter valve is in operation?

Random speculation...

[s4mmie]

Yeah I dunno hey... most emissions delete's I've seen disconnect it and just run a line straight to the booster.

Just thought I'd add that I recently got sick of waiting for my resistors (2 months!) and popped over to Jaycar.
If you go down this route you'll need 1W x 330Ohm for each of the solenoids (N249, N112, etc) and I'd recommend a 10W x 400Ohm or more for the SAI pump.

I just bent the connectors and pushed them into the connectors and taped them up, no need for spade terminals, etc. Cost me all of $2.

Before I put the 470Ohm resistor in the pump I would get a CEL the next day after clearing. 2 days on now and no CEL, touch wood.

[VWindahouse]

In addition to what Sam said I'm up to 20000kms now with no CEL.

This is a cut and paste of mine from another thread regarding this;

Hey mate in regards to the CEL, I remember now what I did to erase the issue once and for all. I threw a code at about 500kms after the delete because I stupidly bought 1 oval and 1 square resistor so had to go to Jaycar to get one of the bare resistors (like the one IE sell for the SAI pump) to go on while I waited for a another round one.

He didn't have a 330 ohm resister so he piggybacked 2 smaller ones which gave a total resistance of about 400 ohms from memory (or maybe a little less) anyway it seems 330 is too little and will through a code. But a bit more resistance does the trick and I have not had a CEL for over 15,000kms

[Jmac]

On top of all that i agree you dont have to wait for the IE ones , granted the valve ones are very tidy. On the SAI pump i find to make it very tidy is to cut the actual plug off the pump ( you are chucking the piece of sh1 away anyway) and tidily solder the resistors onto that plug then simply plug it into the engine bay loom, way better than what ive seen , sorry dont like just sticking male spades into connectors, its untidy for me anyway but most kjnow of my OCD lol. i would rather it look like its meant to be there.
Thats my take , each to their own, its your car. By the way not in any way being negative here just merely giving a tip and my take
Cheers guys
Jmac
ps next one i do ill take a pic, which will be in the next couple of days anyway.

[Paulbag]

Going to delete my PVC system at the weekend. Along with moving some other vacuum pipes, going to be a trial and error process. I'l keep you posted :)

[GTiPilot]

Just went through with the delete today :)

Yet to drive it but will let everyone know how it goes and if I throw a code.

The stuff ontop (#1 & #3) is simple. I tried to put the blanking plate ontop of the vertical shaft rather than loosing coolant - took almost 2 hours fiddling to get the combi valve unbolted only to find the bolt spacing is different (IE Blockoff Plate) and so had to unbold from below anyway!

I found I didn't need to take off the coolant attachment, just loosened the two nuts ever so slightly and could then get in to the upper bolt of the combi valve shaft.

Its all connected back up, still have to do the SAI pump resistor, will probably go down Jmac's recommendation just above and heatshrink it all.

[noone]

Cool. Don't be surprised if it throws a code with resistors.

[DUB80Y]

Hi All

Could someone please clarify, this is a tidy the engine vs a performance mod?

Sorry for the nub question

~graham

[h100vw]

Hi All

Could someone please clarify, this is a tidy the engine vs a performance mod?

Sorry for the nub question

~graham

This is a don't spend $700 on a new air pump mod. However, you will need get a fault code come up if you don't have a tune specifically to cancel it.

The ECU knows it has requested the pump to switch on, but doesn't see the expected change in the exhaust.

I have some blanks for $20 delivered, which can use the standard bolts. This removes the combi valve tower and goes on the side of the head.

http://www.vwwatercooled.com.au/forums/images/imported/2013/08/IMAG1498_zpse504efcd-1.jpg (http://s40.photobucket.com/user/h100vw/media/polo%20gti/IMAG1498_zpse504efcd.jpg.html)

[Adam]

Reading through the past posts, is the culprit the combi valve? My car is developing the issue but not to the point of throwing codes. I am looking at options to fix/remove it. Unfortunately, GIAC don't do a code to remove it the SAI. I can get the parts from O/S for the pump and combi valve for about 750 at the moment. Either way, it's quite expensive. :(

[noone]

Mine is low ks, happy to sell to keep you moving.

[s4mmie]

Personal opinion, just delete it and run with the code.. I've been looking at the stupid light for over a year now, no dramas. I just check the codes every service to be sure.

[noone]

I did for awhile, hated the light. Always made me wonder if there was something else wrong that I wouldn't know about.

[Adam]

I did for awhile, hated the light.

I am the same. I am a bit OCD with warning lights on the dash. What did you do with yours noone?

[dubstar]

This weekend I added the SAI back onto the car. Got sick of the error light.

I actually went with the Mk4 Golf SAI pump as it can be rebuilt if it fails in the future. I just made up some little rubber spacers and away she went.

I also checked the combi valve using a vacuum pump.

My Seatofthepantsometer says the car is running smoother after the re-fit, but can't verify that.

[h100vw]

I am the same. I am a bit OCD with warning lights on the dash. What did you do with yours noone?

Custom-Code tuned with the no code.

Gavin

[noone]

yep, no codes, no vac or SAI systems, enough torque for me (nice after driving a van for a few days).

[Stuwey]

Thinking of doing the N249 delete soon using the IE plugs, but leaving the SAI until I can get my arse into gear and do the APR program to suit.

From the first post, I'm assuming i'll only need the one plug (circle 3 in the photo), as the SAI plug (circle 1) will remain?

Also, along the intake charge pipe from the turbo, there are a number of outlets. Of these, one small one comes up to a 90 degree bend, and turns along toward the passenger side of the car. What is the electrical black box on this part? It can be seen just above the DV clamp in the first photo.

Still don't have full boost, and i'm just thinking out loud here.



Cheers :)

[dubstar]

I've just removed the delete from my car, so I have the IE plug up for sale, if you want it, PM me.

[h100vw]

Thinking of doing the N249 delete soon using the IE plugs, but leaving the SAI until I can get my arse into gear and do the APR program to suit.

From the first post, I'm assuming i'll only need the one plug (circle 3 in the photo), as the SAI plug (circle 1) will remain?

Also, along the intake charge pipe from the turbo, there are a number of outlets. Of these, one small one comes up to a 90 degree bend, and turns along toward the passenger side of the car. What is the electrical black box on this part? It can be seen just above the DV clamp in the first photo.

Still don't have full boost, and i'm just thinking out loud here.



Cheers :)


N75, electrical plug and 3 pipes

[sambb]

Hopefully this isn't a dumbass question but some of the posts only hint at it... I still only have the standard ECU but want to get rid of as much of this gear as I can - particularly the airpump for better access. From what I understand I will throw a code if I do the air pump ( even with correct resisters fitted) because my ECU still wants to see lean mixtures at the O2 sensor on start up - is that correct? If so, is there any part I can delete with the standard ECU without the CEL coming up?

[h100vw]

Basically, no. It's all got to stay.

I have blanks for the side of the head and Phase 1 or Phase 2 software to take care of the incorrect flow code.

Gavin

[noone]

Seriously, a Polo GTI with stock ECU is such a different car, get the tune, all bypasses, etc for <$800 and 1/2 a days efforts. (Hoping my guestimates are ok Gav). If you want the best from it on a budget, the PD160 intake is overpriced for what it is, but really worth it.

No SAI that's prone to failiure, no Vac stuff on top of the engine, no 249 / 112 fiddling with your boost levels (max please).

You cant spend money in a better way on your Polo, best bang for buck, stupid gains in HP and torque. It will unfortunately have the side effect of encouraging you to get suspension work and sticky tyres.

[sambb]

read a few posts here about using 300 ohm 1 watt resistors for the n112 and n249 solenoids. Just wanted to check that that info is correct. I measured the solenoids at 30 ohms which would suggest nearly a 0.5A draw (more like 6+ watts)? Am I missing something??

thanks

[h100vw]

I think that's right Sam. In fact I thought it might even have been a touch bigger. 380 ohm. I had a look in my cupboard but must have used them all.

Gavin

[sambb]

anyone know why the resistor value has to be so high? Surely the solenoid would have to be almost purely resistive. Don't understand what the other 300+ ohms is needed for when it seems you only need 30 ohms to mimic the solenoid. I'll try to tong the n249 solenoid and see what its really drawing?

[h100vw]

VWVortex.com - Installing resistors after removing SAI pump and n249. (http://forums.vwvortex.com/showthread.php?4675108-Installing-resistors-after-removing-SAI-pump-and-n249&p=62441324&viewfull=1#post62441324)

330ohm 10 watt. That's what I am using Sam, I am sure your theory would hold water but if the resistors are too small you get the code up. I ran 300 and then had to go bigger.
Gavin

[rgvlee]

Does the forge sai block off plate fit? The one they make for the mk4 golf gti?

[h100vw]

It would, I have some though. like the one in the cheapy thread.

Gavin

[sambb]

found this on another VAG site RE the resistors:

"I was contacted directly by ***** from ******. He assured me that the resistors he sells have been tested by many and work well and safely. The resistors used for the various solenoids are 330 Ohm and rated for 1 watt. The measured resistance of the actual solenoids is closer to 30 Ohms or so, but in ***** experience (and his customers), the 330 ohm value is sufficient to satisfy the ECU's circuit tests. The higher resistance also makes for lower current and heat in the resistor, which is good."

"The only application I cannot recommend for a resistor is the SAI pump itself. The pump circuit is relay-driven and as such, it is not metered by the ECU whatsoever. Putting a resistor in place of the pump will serve no purpose other than to waste electricity. The resistor would perform a function of keeping the harness connector clean and insulated, but a little bit of electrical tape would do that as well. "

So there you go. 30 ohm resistors would satisfy the ECU checks but would fry themselves and open circuit unless they were minimum 6w and even then would run very hot if soldered into a loom (as they would pull 0.5A). They use 330+ ohms so that the current/wattage/size of the resistor comes down. I thought the ECU would see such low current (40mA 'ish) as an open circuit, but apparently not.

If anyones 300+ ohm n112/n249 solenoid resistor didn't work, possibly it was because the wattage was too low (even 1 watt sounds borderline) and it couldn't dissipate heat when heat shrunk into a loom and then fried internally and open circuited.



"

[rgvlee]

It would, I have some though. like the one in the cheapy thread.

Gavin

You had some laser cut right? Using the stock gasket? Is it a paper gasket?

[h100vw]

You had some laser cut right? Using the stock gasket? Is it a paper gasket?

Stock gasket, which is thin metal. I reused the original and it doesn't leak.

They are laser cut.

Gavin

[rgvlee]

Stock gasket, which is thin metal. I reused the original and it doesn't leak.

They are laser cut.

Gavin

What's the damage, posted?

[h100vw]

What's the damage, posted?

$22 express, don't forget to ask for the delete when you submit the Flashwire request. :D

Gavin

[Jmac]

Ive done a couple of deletes , pretty much pioneered the orig fault with water in the Sai kicking off hysteria lol. Vw still think that washing your car gets water in, shows how much they know, actually knowing how it works does help a lot lol. Anyway Latest one I did I didn't resistor the pump at all only the valves. Software was written to ignore the fault codes. Ive serviced it since year later and the pump connector is still cabled tied out of the way unconnected to anything. If you choose to resistor it you risk a good chance of a fault code, as it does ask for the pump now and again not only at cold start, governed by what the Ecu asks. That's why there is folk getting codes with resistors.
Ta
Jmac