Drilling a drain hole in the intercooler plumbing

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
How would the car behave if you're stuck in traffic in a huge puddle of water? I assume the engine will suck up some (lots) of water through this hole ? Hard to hide after the engine is hydro locked and you're sitting at the dealer.
If you did stop in foot deep water, there is the possibility that some will find its way in. However, since there is not vacuum in that pipe, it will not be sucked in.

To see how much, you could drill a .05", (or slightly less than a 1/16" hole, 1/16 is .0625") in a plastic cup or drinking glass and hold that 6" down into some water and see how quickly it comes in. Me, I will not drive my VW through water, I spent too much money on it to risk water getting into wheel bearings, the transaxle, etc.
 
Last edited:

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
The question is not if the turbo creates a vacuum. The question is if the moving air moving past the hole creates a venturi effect that would draw outside air/junk into the system.


I'd put money down that even a slash cut tube insert facing downstream wouldn't be able to create vacuum even in a transient operating condition in this application. The turbo spools too early, and makes too much boost for the velocity in the pipe.
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
Yesterday I drove for about 3.5 hours, high speed, in town, multiple park for a while and restarts. I would pull the tube off and inspect everything, but this is the weather I'm dealing with. I have a tiny, unheated, un-electrified garage, that is currently blocked by a large snow drift. Yesterday it was below 0 all day, like -2, -4, right now it's about 12 degrees, with 47mph wind gusts blowing the snow all over. Yay. Right now the car is stuck in my yard, I'll have to shovel a little snow later.
 

hotpocketdeath

Veteran Member
Joined
Mar 18, 2010
Location
Suwanee, GA
TDI
2010 Golf TDI
I wanted to chime in with my experience with the question of if the car pulls a vacuum at any point and the answer is yes, it does, but only a very small amount.

I have noticed with Torque, that while idling, the intake could be running at a negative .1 to .2 psi. So even though it is a very low vacuum, it would be enough to draw in air through any openings in the intake system after the turbo. That's enough alone for me to discourage drilling any holes in the intake unless you can seal them up before running the engine.
 

afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
I wanted to chime in with my experience with the question of if the car pulls a vacuum at any point and the answer is yes, it does, but only a very small amount.

I have noticed with Torque, that while idling, the intake could be running at a negative .1 to .2 psi. So even though it is a very low vacuum, it would be enough to draw in air through any openings in the intake system after the turbo. That's enough alone for me to discourage drilling any holes in the intake unless you can seal them up before running the engine.
only thing coming out of my hole at idle is a stream of air, today we woke up to 38 degrees I took a 50 mile ride and my hole was dry, no cel or stored codes, at the moment I'm rebuilding an engine when I'm finished I plan on hooking up a boost/vacuum gauge to my hole, then we can see what the hole does under stress
 
Last edited:

hotpocketdeath

Veteran Member
Joined
Mar 18, 2010
Location
Suwanee, GA
TDI
2010 Golf TDI
only thing coming out of my hole at idle is a stream of air, today we woke up to 38 degrees I took a 50 mile ride and my hole was dry, no cel or stored codes, at the moment I'm rebuilding an engine when I'm finished I plan on hooking up a boost/vacuum gauge to my hole, then we can see what the hole does under stress
In the voice of Archer "PHRASING"

Sorry, couldn't resist
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
I have noticed with Torque, that while idling, the intake could be running at a negative .1 to .2 psi. So even though it is a very low vacuum, it would be enough to draw in air through any openings in the intake system after the turbo.
What the hell is "Torque"? How are you measuring this?
 

msantram

Veteran Member
Joined
Jan 2, 2013
Location
PA & NYC
TDI
2011 SportWagen TDI DSG (Buyback 2018.01.30)
^ Torque is a monitoring app for Android. no real iOS equivalent.
 

Ol'Rattler

Top Post Dawg
Joined
Jul 3, 2007
Location
PNA
TDI
2006 BRM Jetta
Whoever took my thread and put it here, thanks, now I'm considering quitting this forum. No one wants to sift through 100+ pages of this, you've basically taken my info and thrown it away. You want to do something right? Take out 99% of this worthless thread and distill it down to something worthwhile. Otherwise, leave my threads alone.
Seriously, get a grip. This is a FREE public forum. Some of the post you will get will completely save your bacon while others will be completely useless. It's up to you to filter out the nonsense.

I have had my posting privileges here suspended at least once for responding in a derogatory and insulting manner to some really asinine posts............

The only downside I see to drilling a a drain hole is that it might whistle and/or clog over time. Keep us inform on how your idea works.
 
Last edited:

afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
Seriously, get a grip. This is a FREE public forum. Some of the post you will get will completely save your bacon while others will be completely useless. It's up to you to filter out the nonsense.

I have had my posting privileges here suspended at least once for responding in a derogatory and insulting manner to some really asinine posts............

The only downside I see to drilling a a drain hole is that it might whistle and/or clog over time. Keep us inform on how your idea works.

no audible whistle at 75mph, nothing at idle, just puffs of air
 

afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
one thing I did do

I tapered the hole on the inside of the pipe so water and sludge would run to the hole and not pool up around it. The inside of my pipe is clean, no sludge, but car only has 13k miles on it. May take some time to get definitive results, for now I will leave the bottom cover off, this Sunday I plan on a 120 mile frwy trip (75 plus MPH), any problems should show up then since forecast is for a cold spell, 45 degrees or less
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
Seriously, get a grip. This is a FREE public forum. Some of the post you will get will completely save your bacon while others will be completely useless. It's up to you to filter out the nonsense.

I have had my posting privileges here suspended at least once for responding in a derogatory and insulting manner to some really asinine posts............

The only downside I see to drilling a a drain hole is that it might whistle and/or clog over time. Keep us inform on how your idea works.

I was responding with annoyance over my thread being hacked up and put into the giant frozen intercooler thread. When I got this thread reinstated, I responded with appreciation.
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
I tapered the hole on the inside of the pipe so water and sludge would run to the hole and not pool up around it. The inside of my pipe is clean, no sludge, but car only has 13k miles on it. May take some time to get definitive results, for now I will leave the bottom cover off, this Sunday I plan on a 120 mile frwy trip (75 plus MPH), any problems should show up then since forecast is for a cold spell, 45 degrees or less

Just to mention, I'm sure you already know this and this doesn't apply to your freeway trip, but to anyone who doesn't know, the bottom cover seals the engine compartment for a specific purpose. The purpose is to channel airflow out around the exhaust/dfp/etc. That's why the cooling fans come on during a regen. If you leave the bottom cover off, the air won't make it out behind the motor, it'll just go down and out behind the radiator, allowing the exhaust components to get hotter and add more heat to that part of the engine compartment.
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
As far as the torque app (I hate smartphones, instagram, twitter, facebook, all that crap, but I love youtube) I don't know where or how the VW is reading pressure in the intake tract. It is possible that reading may not 100% reflect the pressure in that pipe. I don't know.
 

afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
I'm going with the hole

Today I tried to recreate the conditions that brought about the hydro-lock I experienced a couple of weeks ago...temp 38 degrees, a little colder than before, I drove 70 frwy miles, parked the car and checked the hole, no water beads. The car sat for several hours, started it up checked the hole, no water beads. Drove 30 miles shut it off, restarted after 10 minutes, no water beads. No cel. No stored codes. In my case I believe any water that condenses in my intercooler system is pushed out the hole as I drive and the hole is small enough not to compromise the electronics or software. Car is in my garage, hole is dry believe I will put it all back together and call it a day
 

hotpocketdeath

Veteran Member
Joined
Mar 18, 2010
Location
Suwanee, GA
TDI
2010 Golf TDI
As far as the torque app (I hate smartphones, instagram, twitter, facebook, all that crap, but I love youtube) I don't know where or how the VW is reading pressure in the intake tract. It is possible that reading may not 100% reflect the pressure in that pipe. I don't know.
Torque reads the information directly from the ECU. It's using the same sensors that the car uses for running the engine.

The information comes from the Absolute Manifold Pressure, which is essentially a comparison between the pressure inside the intake to a vacuum. So without the engine running, the AMP would be the same as the outside air pressure, which is around 14.7psi at sea level, less as you go up in altitude.

I worked out a formula within torque that subtracts barometric pressure from the AMP, which basically tells you how much boost your car is making no matter what altitude the car is running at.

Granted you are correct in that the sensors may not be 100% accurate, but seeing the gauge go into the negative has been observed by more than just myself. But as I mentioned before, it is only a very small vacuum.
 

STRANGETDI

Veteran Member
Joined
Sep 20, 2001
Location
East Hampton, CT
TDI
2013 Audi A3 S-Line Premium Plus Quattro - APR Stage II
Does any one have the part number for the hose that we would drill into? Would want an extra just in case.
 

JasonG

Veteran Member
Joined
Nov 20, 2011
Location
Warwick N.Y.
TDI
1994, 2003 JSW (sold), 2012 Jetta
Drilled my hole this afternoon.
Used the size down from a 3/32", I think it was a 5/64" but it was illegible.
Black and brown oily goo dribbled out.
At idle the drip stopped, probably due to a slight engine vacuum.
A few light revs, well, made a mess :( but better to get it out right?

With these ,20°f nights and 40°f days, I've had a gurgle or two.
Very happy for this simple solution.

I was working with 2micron briefly on his drain valve.
The downsides were his work, while top notch, was high end swedged stainless.
Adding a 12v ball valve to that made things just way too expensive. 12v ball valves are not common so they draw a premium price. 24v balls are easy,12v solenoids are common but won't work in a drain/freeze application.
 

Slurry Pumper

Veteran Member
Joined
Sep 13, 2012
Location
Allentown PA
TDI
2010 Jetta Sedan
I have never experienced this problem on my car. When I had my DPF deleted, the dude asked if I wanted an EGR delete as well, and I said sure, does this have any effect on the fluid build up in my intercooler? Or am I drunk again this morning already?
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
Torque reads the information directly from the ECU. It's using the same sensors that the car uses for running the engine.

The information comes from the Absolute Manifold Pressure, which is essentially a comparison between the pressure inside the intake to a vacuum. So without the engine running, the AMP would be the same as the outside air pressure, which is around 14.7psi at sea level, less as you go up in altitude.

I worked out a formula within torque that subtracts barometric pressure from the AMP, which basically tells you how much boost your car is making no matter what altitude the car is running at.

Granted you are correct in that the sensors may not be 100% accurate, but seeing the gauge go into the negative has been observed by more than just myself. But as I mentioned before, it is only a very small vacuum.
Yeah, I know what a MAP sensor is. MAP, not AMP. Instead of working out a formula, try this. Engine off, look at the reading. That will be your reference point, atmospheric. Then engine on, look at the reading.

What I was getting at is where that sensor is, somewhere in the intake manifold, may not 100% reflect the pressure in that charge air pipe.
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
I have never experienced this problem on my car. When I had my DPF deleted, the dude asked if I wanted an EGR delete as well, and I said sure, does this have any effect on the fluid build up in my intercooler? Or am I drunk again this morning already?
I can't answer your question about whether or not you're drunk, but day drinking is winning. I don't why everyone else goes out at night. Like a bunch of sun hating vampire weirdos. Maybe because they are ashamed of what they do, and prefer to keep it in the dark?

Anyway, back to the tech info, you're not going to have much water buildup at all without the low pressure EGR. The only water vapor you'll get in the intercooler is from blowby, via your crankcase ventilation system. If you want to read how the EGR works, here's a link, I think the mk6 info starts about halfway down the page or so. http://www.myturbodiesel.com/wiki/egr-system-faq-for-vw-and-audi-tdi/
 
Last edited:

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
Drilled my hole this afternoon.
Used the size down from a 3/32", I think it was a 5/64" but it was illegible.
I really want to emphasize, drill these holes SMALL, you guys! Like smaller than 1/16". That way it'll lessen the chances of anything going wrong and anyone blaming me!!
 

hotpocketdeath

Veteran Member
Joined
Mar 18, 2010
Location
Suwanee, GA
TDI
2010 Golf TDI
Yeah, I know what a MAP sensor is. MAP, not AMP. Instead of working out a formula, try this. Engine off, look at the reading. That will be your reference point, atmospheric. Then engine on, look at the reading.

What I was getting at is where that sensor is, somewhere in the intake manifold, may not 100% reflect the pressure in that charge air pipe.
Yes you are right, MAP, typo.

And I don't think you quite understood what I was saying, the formula I worked out for Torque is doing exactly what you are suggesting, except in real-time. The formula is specifically for the Torque app so that it can work out what the correct boost is based on what the car is reporting. This is what it looks like: PID70 (((D*256)+E)/32)-([ff1270]*.1). [ff1270] is the sensor that measures barometric pressure.

I understand that not all sensors are 100% accurate, but as I said, I'm not the only one who has observed a negative boost in this area. When you have multiple people reporting the same information, you can safely assume the information is correct.
 
Last edited:

Ppolaris1010

Well-known member
Joined
Jan 2, 2015
Location
Ct
TDI
2013 jetta sportwagen
I drilled mine Friday and drove it all weekend no issues took a look today and no water. Devices to make a little filter for it. Only thing that worries me is all the oil more than expected took pics but can't figure out how to post them.probably going to try to glue a barb on it and put a shut off for summer
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
I really want to emphasize, drill these holes SMALL, you guys! Like smaller than 1/16". That way it'll lessen the chances of anything going wrong and anyone blaming me!!
Oh, we're gonna blame you! And I don't even own one of these prissy buckets.

Disclaimer: I've been night drinking.
 
Top