Hard Start / No Start - Is your intercooler frozen? Check Here!

[GraniteRooster]

Now I really want to know more, maybe the new IC has a vacuum operated valve, that is where all of the magic is!!! That would make the most sense, basically taking the IC out of the equation when the temperature is low, what a great idea. Now can someone please confirm this? maybe the self study document from VW has more info?

To take the IC out of the equation, VW would need to provide an alternate flow path for the intake air. This could be perhaps built into the body of a new IC, or installed as a bypass hose. Unless the new equipment package has these features, I would not see evidence that it is an IC bypass valve.

Now for the love of all things diesel - can anyone explain to me why this forum has a sticky for a tire light NON-issue, but there is no sticky for this TSB??

 

[eddif]

What are the symptoms of water in the intake system (?) :

1..Water in the hose.
2..No start when water is enough to thaw and re-freeze and block the air flow.
3..Enough frost while driving to stop the air flow?
4..A minor un-noticed hydrolock that just bends a rod / rods a minor amount (just enough to cock a piston and cause high cylinder wear). Cocked pistons and rings cause uneven cylinder wear and thus would probably drive up the Fe in UOA reports.
5..A more severe hydrolock that causes a locked engine at start. This may can cause a leaking head gasket or rod bent enough to cause a miss, coolant in the oil, or other problem.
6..Just enough moisture left in the cylinders to cause rust at times.
7..Other things?

Can a lot of symptoms of the cars actually be caused by the water / goo?

Who else has a different list or more possible results of the moisture / water ingestion?

eddif

 

[bhtooefr]

Yes, that makes more logical sense, although it's not what the person said.

Actually, it is what the person said, rephrased, and read using actual logic, rather than sky-is-falling paranoia.

 

[MayorDJQ]

Let me know when you have more than speculation.

Until one of us gets a job on the executive board of VWoA, all we'll have is theory and speculation.

In the 10+ years of TDIClub, speculation has lead to a lot of discovery.

 

[nicklockard]

To take the IC out of the equation, VW would need to provide an alternate flow path for the intake air. This could be perhaps built into the body of a new IC, or installed as a bypass hose. Unless the new equipment package has these features, I would not see evidence that it is an IC bypass valve.

It isn't necessary to completely bypass the intercooler. An internal flap which directs most of the air mass toward a straight-through path through the IC will speed up the air velocity through that section. The faster the air travels through the IC, the less it's cooled because heat transfer depends on: material and residence time (inverse to velocity). Faster air = lower residence time in IC = less cooling = warmer output = moisture stays in (supersaturated state) dissolved suspension rather than condensing out.

Now for the love of all things diesel - can anyone explain to me why this forum has a sticky for a tire light NON-issue, but there is no sticky for this TSB??

LOL.

 

[GraniteRooster]

It isn't necessary to completely bypass the intercooler. An internal flap which directs most of the air mass toward a straight-through path through the IC will speed up the air velocity through that section. The faster the air travels through the IC, the less it's cooled because heat transfer depends on: material and residence time (inverse to velocity). Faster air = lower residence time in IC = less cooling = warmer output = moisture stays in (supersaturated state) dissolved suspension rather than condensing out.

The above is true, and basically follows my comment about being integral to the body of the IC. Most IC's dont have geometry like you suggest built in the inlet section that would allow a flap such directional control over the flow path. It would be best to direct it to a tube sections with with no fins, to minimize surface area.

 

[nicklockard]

Sorry, to clarify: an internal (to the inlet tube) flap is what I meant. There are no sections without fins, AFAIK.

 

[kenford]

I tried posting the TSB paperwork I have and it did not work. I can email it to someone if they would like.

 

[soulflyer]

I've got 5000km with the new kit and could not notice any change in mpg or other behavior...
And just to reiterate, I had to tell the dealer about the TSB, but once the service manager read it he said its a 'no-brainer' and i had it installed within 48 hrs.

 

[GraniteRooster]

I read back through the last few pages and first hand descriptions of hardware, and can't reconcile a couple of things:

I dropped my JSW off yesterday for the kit installation and asked to see the parts. I was particularly interested in the new elbow with the fitting in it. As best I could tell there appears to be a brass-colored sensor with tiny holes protruding in the airstream with three vacuum line connections on the outside.

This sounds like a Pitot tube, used for fluid velocity measurement.

FWIW, I had a chance to look at the installed kit...the only thing I can see is that the new elbow with the sensor is installed right before intake plenum... The three vacuum lines make their way up to other vacuum lines in various sensors on the air just entering the turbo.

The elbow before the plenum is a reasonable place for a Pitot tube - measure flow velocity through a known tube area and combined with MAP sensor you now have true intake mass flow measurement. So if VW knew mass flow - what would they do with that info to affect IC icing?

Had the fix for this issue installed on my Jetta yesterday. Took almost 7 hours. No noticeable differences in the way the car runs. Time will tell. Looking at a copy of the TSB install instructions have a better idea of what the new elbow is.
The piece coming out of the side is a temperature switch with 2 nipples, one for a ventilation hose to the air cleaner, another to a vacuum source and the larger fitting for a hose to the charge air cooler regulator flap.

This description is nothing at all like B25's - mysterious

I went to the VW dealer today to schedule my kit install and they had not done one yet. They had a kit on the shelf they just received, but would not open the "sealed box" until the service appt . So I did not get to see parts, and am no closer to understanding this

Kenford perhaps you could email me your TSB info? PM sent - thanks

 

[MayorDJQ]

This sounds like a Pitot tube, used for fluid velocity measurement.

The elbow before the plenum is a reasonable place for a Pitot tube - measure flow velocity through a known tube area and combined with MAP sensor you now have true intake mass flow measurement. So if VW knew mass flow - what would they do with that info to affect IC icing?

This description is nothing at all like B25's - mysterious

Isn't a Pitot tube basically measuring changes in atmospheric pressure....i.e. vacuum or boost?

I think you're getting off track. Maybe VW is looking at measuring something other than airflow in the air intake system.....but what else is there to measure?

 

[nicklockard]

Isn't a Pitot tube basically measuring changes in atmospheric pressure....i.e. vacuum or boost?

I think you're getting off track. Maybe VW is looking at measuring something other than airflow in the air intake system.....but what else is there to measure?

Absolute humidity, or mass airflow.

 

[40X40]

I think that all the 'kit' does is:

When certain conditions are met, exhaust gas (that is 'WET') is prevented from passing through the intercooler. (That is, EGR is turned OFF(but not all the time).)

What do you guys think?

Bill

 

[eddif]

I think that all the 'kit' does is:

When certain conditions are met, exhaust gas (that is 'WET') is prevented from passing through the intercooler. (That is, EGR is turned OFF(but not all the time).)

What do you guys think?

Bill

I tend to agree that is one possible use of the new kit. In the case of the old air-cooled VW carburetor icing, one of the major times of icing was when the engine was stone cold (do not freak that the air-cooled is mentioned).

The engine is so complex there may be other present or possible future uses for the kit. Other hardware parts may also be added to use the information given by the added sensors and parts in the present kit. I would hope there are spare logic circuits in the existing computer for more added features.

eddif

 

[oxford_guy]

Actually, it is what the person said, rephrased, and read using actual logic, rather than sky-is-falling paranoia.

No, it's not what the person said.

What was actually said:
"If you've had your car towed to the dealer on more than one occasion because of this, i can't imagine they wouldn't install the kit."

Your version:
"If owners have had their car towed more than once, there should be no problem at all getting it, but that probably isn't necessary, as long as the issue is documented."

Those are two very different statements. The italicized part of your statement is nowhere to be found in the original, and it's contradictory given the first part of the sentence ("towed more than once"). Also "There should be no problem at all" is overstated. Adding things that aren't there isn't logic, nor is taking issue with problematic statements paranoia.

 

[tcp_ip_dude]

[snip]

The engine is so complex there may be other present or possible future uses for the kit. Other hardware parts may also be added to use the information given by the added sensors and parts in the present kit. I would hope there are spare logic circuits in the existing computer for more added features.

eddif

These are micro-processor based systems, added functionality is accomplished via software updates. The days of old analog based logic circuits are long gone.

 

[Maine12]

So is the factory installing the updated intercoolers in the new 2011's or would you have to wait for the 2012 model?

 

[740GLE]

I just did my 40K service and noticed quite a bit of oily drippings on the driver side piping, I cracked it open nothing other than a film or so of oil. The fitting did seam loose as others have noted. The passenger’s side was a bit different. As I cracked it open, relatively clear (slightly gray) water came out, probably 1 table spoon total, easily dripped right out. Inside was the same green sludge I noticed back at my 20K service. I cleaned everything back up, and we’ll see what happens this winter.
The real kicker is, I just put 500 miles on it this past weekend, temp ranges from 70-90, humidity levels were pretty decent. Drove aggressive with a rack and bike on the roof. This morning 65 degrees and 80+% humidity, drove into work 50 miles, picked up 3 of my coworkers (full sized adults) and did 70-75 on the highway. I wasn’t babying it accelerated swiftly, shifted at 3K at each stop for a coworker, and still there was water in the IC. How aggressive do you have to be, when going 50 miles on the highway at 75 carrying 800# of manflesh for nothing to accumulate?

 

[bhtooefr]

I'm actually not convinced that the trick is being aggressive, to trick it with driving style.

I think the trick MAY be, long trips, and baby it, with occasional WOT blasts shifting at 4k+ to get the soot out. The idea there is, the low-pressure EGR kicks in when the high-pressure EGR is ineffective - under high load. But, that's just speculation, and that technique can be bad on other things.

 

[MayorDJQ]

Why would the HP-EGR be ineffective at high RPMs?

 

[740GLE]

Also there was no soot in the IC, it was all oily goop with a light greenish tint, with residual watter sitting on top. Maybe the soot turns this color after sitting there for a while.

BTW my Exhaust flapper valve moved freely, very clean action, so i'm happy with that.

 

[bhtooefr]

Why would the HP-EGR be ineffective at high RPMs?

High load, not high RPMs.

Under high load, you'll get a reduction in boost, and potentially boost pushing the exhaust gases back through the turbo, with the HP-EGR opened. This is why, under load, the HP-EGR is closed on older TDIs, and why driving it like you stole it is a valid way to avoid intake clogging on those.

 

[GraniteRooster]

New IC Kit

I read back through the last few pages and first hand descriptions of hardware, and can't reconcile a couple of things:

This sounds like a Pitot tube, used for fluid velocity measurement.

The elbow before the plenum is a reasonable place for a Pitot tube - measure flow velocity through a known tube area and combined with MAP sensor you now have true intake mass flow measurement. So if VW knew mass flow - what would they do with that info to affect IC icing?

This description is nothing at all like B25's - mysterious

I think have reconciled my previous questions. My car is having its new IC kit installed this AM. The parts kit has:

1) New IC with vacuum operated flap valve on the inlet end

2) New elbow with sensor - round brass plug about 3/8", dia that sticks through the elbow wall into the airstream about 3/8-1/2". Body of sensor has (3) air lines labeled "ATM", "VAC" and "OUT". I did not see three tiny holes drilled in the plug, nor is it shaped correctly for a Pitot tube. Seems like a temp probe/actuator to me - no visible sensor orifices machined into the brass, no electrical connections.

3) hoses to connect 1) and 2) above with each other and the rest of the car.

The IC has a vacuum operated flap on the inlet that you can hear metal-on-metal "clank" when it closes against internal passages in the casting of the aluminum casting of the IC inlet diffuser.

Based on these observations, my guess is the brass plug is a temperature sensor/actuator, that actuates a mixing valve and blends "VAC" and "ATM" as required to produce "OUT" that is then fed to the IC flap regulator to control position and cooling airflow through the IC based on temperature. You cant see the flap inside the IC from the outside, but from the location of the actuator and the nature of the "clank" - I guess that the plate blocks off about the the upper 2/3-3/4 of the IC when closed, and leaves the bottom 1/4-1/3 open and free flowing.

I apologize that I did not take pictures - perhaps I will take some once installed to show final installation, and maybe someone else can take pics of the hardware before their kit is installed.

 

[740GLE]

Tulley doing this?

 

[GraniteRooster]

Tulley doing this?

2nd one they've done

 

[GraniteRooster]

Here's an idea - temperature controlled IC louvers that open and shut to block off IC. Maybe not practical as an OEM retrofit - but a neat idea to think about.

OK - so it seems VW liked my basic concept enough to use it and adapt to the TDI. You're welcome VW!! Thanks for reading Fred's TDI. Now about my consulting fee and the remainder of my TDI payments...

My uncles 1937 Rolls Royce's has bimetalic louvers infront of the radiator that act as the thermostat. When the engine bay heats up enough you can see the louvers rotate to let air in, pretty amazing IMO. Not sure if this could work here, but interesting none the less.

Interesting that VW essentially chose an updated, modern version of this approach. Pretty clean fix IMO. Good lesson in applying the principles learned and honed by those generations before us.

 

[740GLE]

Sounds like what your discribing is the internal geometry of the IC changing depending on what the ECU says. A little different than blocking off the IC, but still interesting solution.

I wonder if we can do some IAT year round before and after and see if it'll change on the hot days.

 

[El Dobro]

What we need is someone to check the hose around 1000-1500mi. and see if there's anything built up in there.

 

[nicklockard]

Sounds like what your discribing is the internal geometry of the IC changing depending on what the ECU says. A little different than blocking off the IC, but still interesting solution.

I wonder if we can do some IAT year round before and after and see if it'll change on the hot days.

It sounds like it's purely mechanically controlled based on pressure differentials at certain temperatures. Somebody went and reviewed their first year engineering thermodynamics/psychrometrics Good on you V-dub

And, there's a good chance this will increase winter fuel economy a healthy 2mpg at least, and more for winter city driving. I predict a nice bump in overall city fuel economy for those with this kit.

Now let's just hope the flapper valves don't seize on goop which is also likely to happen to some.

2 predictions! Count 'em

 

[nicklockard]

OK - so it seems VW liked my basic concept enough to use it and adapt to the TDI. You're welcome VW!! Thanks for reading Fred's TDI. Now about my consulting fee and the remainder of my TDI payments...



Interesting that VW essentially chose an updated, modern version of this approach. Pretty clean fix IMO. Good lesson in applying the principles learned and honed by those generations before us.

*Ahem*

Far closer to MY idea (post #905 and #907)



VW, please send me my new Tdi with lifetime HPFP warranty as payment for this consultation. Thanks