Drilling a drain hole in the intercooler plumbing

SundanceGS

Well-known member
Joined
Feb 12, 2013
Location
Woodbridge, VA
TDI
2010 Jetta TDI Cup Edition (bought back), 2015 Porsche Cayenne Diesel (Totaled), 2013 Audi Q7 TDI (current)
If drilling a small hole solves the problem then I am interested

Hello all,

I've had multiple issues even after getting the cold weather intercooler installed. I'm tired of wondering whether my car will start after I drive it in cold, humid weather so I may give this drill idea a shot... It would really be interesting if this solves the hard start issues.

Can anyone tell me the purpose behind drilling the hole in the plastic as opposed to the rubber hose portion? It seems that the rubber hose may be cheaper/easier to replace if things go awry, but I don't know if that's where the water collects or not.
 

JASONP

Top Post Dawg
Joined
Feb 24, 2008
Location
Guelph
TDI
2015 Golf TDI Comfortline 6spd
Hello all,

I've had multiple issues even after getting the cold weather intercooler installed. I'm tired of wondering whether my car will start after I drive it in cold, humid weather so I may give this drill idea a shot... It would really be interesting if this solves the hard start issues.

Can anyone tell me the purpose behind drilling the hole in the plastic as opposed to the rubber hose portion? It seems that the rubber hose may be cheaper/easier to replace if things go awry, but I don't know if that's where the water collects or not.
If it doesn't work you can put a self tapping SS screw in place to seal it back up, rubber wouldn't hold a screw as well .

Sent from my SM-G900W8 using Tapatalk
 

afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
my hole took me to see Reba last night

Drove. Alone. Tickets and food, free. 410 miles round trip, just got home. Going and returning speeds oscillated, for the majority of the trip, between 80 and 105 mph. Weather too mild to condense water, hi 60's, lo 70's. No cell's or stored codes. Car performed great. Drill baby drill!
 

elitegunslinger

Veteran Member
Joined
Apr 26, 2010
Location
Barnegat NJ
TDI
2010 Golf TDI :D
I'll probably get flamed for this but I've got to ask:

It seems a little insane to poke a hole in a pressurized system and not plug it back up because it's too difficult to get under a car and remove a plastic belly pan. Each oil change I drain out each pipe and barely get anything out of them, mostly oil if anything but that is expected.

I understand the hole is small but there's got to be a down side to creating a boost leak.
 

Aztraveler

Veteran Member
Joined
Jul 14, 2012
Location
Charlotte, NC
TDI
Sold 2014 Jetta back to VW in 2016. In Oct 2020 Bought 2015 Passat TDI SE CPO
That has been part of the discussion. Consensus seems to be, is the hole so small, boost loss in negligible.

Several of us are subscribed to this thread, eagerly awaiting reports like the one from afarfalla in the post before yours, elitegunslinger.

SundanceGS, Another solution mentioned for sealing the drilled hole in the plastic, was JB Weld. Again not a good solution for sealing a hole in the rubber hose.
 

SundanceGS

Well-known member
Joined
Feb 12, 2013
Location
Woodbridge, VA
TDI
2010 Jetta TDI Cup Edition (bought back), 2015 Porsche Cayenne Diesel (Totaled), 2013 Audi Q7 TDI (current)
That has been part of the discussion. Consensus seems to be, is the hole so small, boost loss in negligible.

Several of us are subscribed to this thread, eagerly awaiting reports like the one from afarfalla in the post before yours, elitegunslinger.

SundanceGS, Another solution mentioned for sealing the drilled hole in the plastic, was JB Weld. Again not a good solution for sealing a hole in the rubber hose.
Yes, I can see the logic in that and it makes sense. Thanks to you guys for pointing it out. Looks like I will drill into the plastic if I decide to go this route.

As far as plugging the hole and simply draining it every oil change, I thought about that as well, but I'm not sure that would be effective... At least not in my case. I believe that my car can condense/freeze enough water to cause me an issue pretty quickly (within 20 or so miles) when the weather conditions are right.

Of course, I could always just put the car up on the ramps, take off the bottom cover, and drain when I know the weather conditions are likely to cause the problem, but it's no fun to do that when it's 20 degrees out. And that would get old quickly... Plus, I'd feel pretty foolish doing that at my workplace's relatively warm underground garage whenever I make the 35 mile commute in cold, humid weather.

I think the thing that makes this potential drilling solution so attractive is that it might work with no additional actions needed from me (which is the type of engineering control I desire as as opposed to an administrative one that only works when/if I take a specific action at a specific time).
 
Last edited:

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
It seems a little insane to poke a hole in a pressurized system and not plug it back up because it's too difficult to get under a car and remove a plastic belly pan. Each oil change I drain out each pipe and barely get anything out of them, mostly oil if anything but that is expected.

I understand the hole is small but there's got to be a down side to creating a boost leak.

I'm quoting myself for the third time in this thread here, all you guys talking about valves and resealing the hole, please read this, let us know what you think.


Anyway, I really want to emphasize one thing here that has been brought up repeatedly. I do NOT want a valve on that pipe. The reason why the people who've said things along the lines of "it's okay as long as you plug it back up", is psychological, not based on engineering. They think because the hole "isn't supposed to be there" that a valve is better, without looking at how the idea of the hole actually works. With a valve, you're not going to know when to open it. You won't know when water is accumulating, or when ice that is going to melt later is forming. You might never open it at the right time, you might open it when the water is still ice, and think there's nothing there. You might forget to open it. You might have to open all the time, way too often.

With the hole, it drains any time water is there. Whether you're driving, whether the car it parked, whether you're there or not. Therefore the hole is a much better idea. Human effort and error factor is out of the equation.
 

Aztraveler

Veteran Member
Joined
Jul 14, 2012
Location
Charlotte, NC
TDI
Sold 2014 Jetta back to VW in 2016. In Oct 2020 Bought 2015 Passat TDI SE CPO
I agree just a hole. Simple. No valve. To me a valve can cause problems. Valve freezes up and is damaged. You may be worse off than before.

If the hole freezes up, it will thaw once it warms up and the water will drain.

If you find the hole causes issues. Epoxy it closed.

Sent from my SCH-I605 using Tapatalk
 

SundanceGS

Well-known member
Joined
Feb 12, 2013
Location
Woodbridge, VA
TDI
2010 Jetta TDI Cup Edition (bought back), 2015 Porsche Cayenne Diesel (Totaled), 2013 Audi Q7 TDI (current)
I agree just a hole. Simple. No valve. To me a valve can cause problems. Valve freezes up and is damaged. You may be worse off than before.

If the hole freezes up, it will thaw once it warms up and the water will drain.

If you find the hole causes issues. Epoxy it closed.

Sent from my SCH-I605 using Tapatalk
I agree as well. Unless there's a button on the dash that reads "Dump intercooler crap out" and a valve opens when I press it, and then properly closes, I'd rather have a drilled hole that provides the solution even when I'm asleep at the wheel (so to speak).
 

SundanceGS

Well-known member
Joined
Feb 12, 2013
Location
Woodbridge, VA
TDI
2010 Jetta TDI Cup Edition (bought back), 2015 Porsche Cayenne Diesel (Totaled), 2013 Audi Q7 TDI (current)
You know, it struck me after I just wrote my last post, if this issue was occurring to my wife's Honda Accord I would not stop raving about getting rid of the hunk of junk and swearing to never buy a Honda product again.

Interesting that I am spending so much time trying to figure out a solution for my VW and my raving has, so far, been pretty minimal. I guess that illustrates how much I love this car and how much I think her Accord is a soul-less appliance. There is no joy in driving that thing...

She said she'll drive it until it dies and then we can maybe get a GTI or a TDI with a non-icing intercooler. Dang, I wasn't thrilled to hear the "until it dies" part. We'll probably be on the Mark X Golf by that time... If I'm lucky.
 

ATR

Top Post Dawg
Joined
Jun 18, 2005
Location
Baltimore
TDI
2011 Golf TDI 6MT
You know, it struck me after I just wrote my last post, if this issue was occurring to my wife's Honda Accord I would not stop raving about getting rid of the hunk of junk and swearing to never buy a Honda product again.
Interesting that I am spending so much time trying to figure out a solution for my VW and my raving has, so far, been pretty minimal. I guess that illustrates how much I love this car and how much I think her Accord is a soul-less appliance. There is no joy in driving that thing...
She said she'll drive it until it dies and then we can maybe get a GTI or a TDI with a non-icing intercooler. Dang, I wasn't thrilled to hear the "until it dies" part. We'll probably be on the Mark X Golf by that time... If I'm lucky.
Funny you should say that... My last car was a bit rare.
2006 Honda Accord EXL ("L" for leather) with a 5 speed manual gearbox. I wouldn't quite call it a appliance. It certainly had more Road feel with a sporty ride then a similar Toyota camry (now THAT is a true rolling appliance).

Main reason I traded it for my current 2011 golf tdi is the massive amount of leg & head room. Seriously, I have more headroom on my car then I do in most others without a sunroof and that's with a sunroof in my golf!

You're right on point that if my Honda gave me any of the issues that I too would have sworn off Honda. While they do make a nice car they recently killed off double wishbone front suspension that helped them have a sport sedan feel. For that reason Mazda gets my vote for anyone looking for a car that is easy to take care of yet still has a good road feel. Sadly after looking at Mazda for my next car I ditched the idea after I visited the dealership. I found a severe lack of headroom even though they didn't have a sunroof installed :eek:

For those looking for a bit more in a car vw will get a nod. Seriously, the Golf tdi is a baby audi! :cool:
 

JasonG

Veteran Member
Joined
Nov 20, 2011
Location
Warwick N.Y.
TDI
1994, 2003 JSW (sold), 2012 Jetta
New thread needed: Dealing with sludge on belly tray.

Seriously y'all, it's getting nasty down there.
I can't believe we've been sucking this stuff through our engines!
 

SundanceGS

Well-known member
Joined
Feb 12, 2013
Location
Woodbridge, VA
TDI
2010 Jetta TDI Cup Edition (bought back), 2015 Porsche Cayenne Diesel (Totaled), 2013 Audi Q7 TDI (current)
Seriously y'all, it's getting nasty down there.
I can't believe we've been sucking this stuff through our engines!
Have you been having icing that then thaws and drips through the hole onto the belly pan? Or is the accumulation the result of crap generated by just normal driving in above freezing temps?
 

path23dv

Veteran Member
Joined
Feb 24, 2009
Location
New Jersey
TDI
2009 Jetta
SundanceGS,

My experience has been that I could accumulate enough water/ice in two weeks to cause a no start condition.

I had a frozen inter cooler in:

December 2009(towed to dealer, removed ice, dealer opened a report with VW)
December 2010(I cleared the ice myself)
November 2013(I cleared the ice, took it to the dealer, I asked for intercooler kit. VW would only pay for parts since I had 70K+ miles. Labor was quoted at $800. I did not have the kit installed)
December 2013(at this point I left ramps in my driveway and drove up after work. At least I could easily clear it if it happened again)
Twice in January 2014

Sold the car in April 2014.
 

SundanceGS

Well-known member
Joined
Feb 12, 2013
Location
Woodbridge, VA
TDI
2010 Jetta TDI Cup Edition (bought back), 2015 Porsche Cayenne Diesel (Totaled), 2013 Audi Q7 TDI (current)
SundanceGS,

My experience has been that I could accumulate enough water/ice in two weeks to cause a no start condition.

I had a frozen inter cooler in:

December 2009(towed to dealer, removed ice, dealer opened a report with VW)
December 2010(I cleared the ice myself)
November 2013(I cleared the ice, took it to the dealer, I asked for intercooler kit. VW would only pay for parts since I had 70K+ miles. Labor was quoted at $800. I did not have the kit installed)
December 2013(at this point I left ramps in my driveway and drove up after work. At least I could easily clear it if it happened again)
Twice in January 2014

Sold the car in April 2014.
Hi Path,

Sounds a lot like the experiences I've had... even down to the part where I would also park on the ramps when I got home at night just in case the car wouldn't start in the morning. My Cup Edition is lower than the regular Jetta and there's no way I can fit underneath unless it's up on the ramps. I did have one instance that it wouldn't start while up on the ramps... I couldn't believe how much water came out when I crawled under and loosened the hose.

Is the icing the reason you sold your car?

I have high hopes that my drilled hole will make things better... if not, I've determined the best alternative is to ask my dad to give me back my other car that he's using and to take this one instead. He lives in Tucson, AZ so I seriously doubt he'll have any icing issues. It's more likely the intercooler will melt than ice up, I think. :)

On a positive note, my car that he's using is a BMW 335d. Wow, that thing is a beast... though I must admit that I would miss the 6 speed manual on my TDI.
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
Sold the car in April 2014.
I bet it has to be a little frustrating to realize you sold the car over the cost of a $2 drill bit. Hopefully you got a car you like better than the VW.

I think my next car is going to be older, not newer. I don't need to be caught up in this money money money image status thing, I just want good, simple engineering. Like an older infiniti G35.
 

path23dv

Veteran Member
Joined
Feb 24, 2009
Location
New Jersey
TDI
2009 Jetta
Not frustrating at all! $11K+ in the bank and I'm driving my old, boring but reliable 2007 Camry. No worries this winter. Life is good.
 

afarfalla

Veteran Member
Joined
Nov 6, 2006
Location
sugar land tx
TDI
05 Passat sedan and 05 wagen
played with my hole today...was I surprised

https://www.flickr.com/photos/37674324@N07/sets/72157649977366159/ now read post 154. no boost at idle, at 2500 rpm's just under 4. Slurry did find its was to a drain hole on the left to coat the underside of the pan. Signs of oil and water with white components in mixture, this all happened after my 400 mile drive, remember the weather was hi 60's low 70's, did not expect this result?? So glad I drilled!
 
Last edited:

DubFamily

Veteran Member
Joined
May 30, 2012
Location
Swan Point, MD
TDI
2014 BMW 328D xDrive
Yeah; glad it works for you. Just no way I am intentionally creating a boost leak in my turbocharged car, sorry.

Still waiting on a better solution, but I do enjoy these posts ;)
 

truman

Top Post Dawg
Joined
May 18, 2000
Location
columbia,MO,usa
TDI
'05 Passat Variant, Still miss the 03JW
Yeah; glad it works for you. Just no way I am intentionally creating a boost leak in my turbocharged car, sorry.

Still waiting on a better solution, but I do enjoy these posts ;)
Which poses the greater risk- waiting for VW to create another Rube Goldberg solution or drilling a small hole, that can be reversed, if you lose sleep over it? Do I hear crickets? Drain hole might be the best mod ever for those who are afflicted by VW's design fax pas. Chance of hydrolock versus chance of what?
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
If the idea is putting the catch can in line with the cooled post DPF EGR, to condense the water vapor out before it gets to the intercooler, that might be a good one. The hole with the oem egr intact still keeps everything cleaner though, because that vapor takes some of the nasty oil from the crankcase blowby out of the hole with it.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
La Conner, WA
TDI
2018 Tesla Model 3: 217,000 miles
You would need a desiccant or some other method of dehumidifying the air. A basic catch can isn't going to remove very much humidity from the air stream (if any). And if you use something with a desiccant, it will need to be recharged (dried out) regularly.

You could put a catch can on the CCV to try and reduce the amount of oil vapor that gets introduced into the charge air system. That should remove some of the sludge that is being blown out of the newly-drilled hole.
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
Which poses the greater risk- waiting for VW to create another Rube Goldberg solution or drilling a small hole, that can be reversed, if you lose sleep over it? Do I hear crickets? Drain hole might be the best mod ever for those who are afflicted by VW's design fax pas. Chance of hydrolock versus chance of what?
People who are resistant to the idea are resistant purely for psychological reasons. Like I wrote before, they think the hole "isn't supposed to be there" and that's that. Well, in my mind, oil and water vapor aren't "supposed" to go through an intercooler, so the tiny hole psychologically appeals to me.
 

2011tdiproject

Veteran Member
Joined
Dec 22, 2013
Location
south dakota
TDI
2011 Golf
You would need a desiccant or some other method of dehumidifying the air. A basic catch can isn't going to remove very much humidity from the air stream (if any). And if you use something with a desiccant, it will need to be recharged (dried out) regularly.

You could put a catch can on the CCV to try and reduce the amount of oil vapor that gets introduced into the charge air system. That should remove some of the sludge that is being blown out of the newly-drilled hole.
A catch can will take out water vapor if it's at a lower temperature than the air going into it, or below the "dew point". You just wouldn't want the water to freeze in the can. So you might have to drill a hole in the bottom of the catch can instead. Lol
 
Top