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

RebelTDI

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I put my 2010 Golf up on ramps and checked the hose to the intercooler, as shown by DHall. I had maybe 2 Tbsp of greenish water which I drained and mopped up with paper towels. It was a relief to not see much water, but there was a little. BTW, getting the under cover back on was not my favorite job. I do understand the Panzer plate rationale now, though. The plastic looks flimsy. Thanks for the photo, DHall.
 

tcp_ip_dude

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I checked my Intercooler tube today on my '10 Jetta with 15K miles, there was some lite residue there, but only enough to coat my finger and a paper towel. Pictures made with phone didn't turn out, so I have nothing to post, but there was definitely no standing liquid/goo, just light residue.
 

Ski in NC

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Ok. I can accept the fact that at 25 degrees the air would be cold enough to freeze water, but at 25 degrees it takes longer for water to freeze than it does at 15, 10, -10 etc. There's also constant airflow through the intercooler and the intake tract, which should be moving air fast enough through the intercooler to prevent any water vapor from sitting on the intercooler long enough to freeze.

I would still say it would take almost unheard of humidity for this to happen. And my $64K question is - Why didn't we see this on the older TDIs?
My bet is that the newer cars run higher boost at cruise conditions, in part due to the lower revs. Higher pressure in intercooler brings the condensation temperature up. We need someone with a new car to go for a ride with vcds or scangauge to see what boost is.

Also, if egr is introduced pre turbo compressor suction (it does right???) that will increase relative humidity of the intake flow.

Frosting will occur without regard to air velocity. Like that lighthouse in Ohio.
 

IndigoBlueWagon

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Older cars may not be as thermally efficient, and they certainly don't have as effective intercoolers. They also have smaller piping that may accelerate airflow.
 

El Dobro

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They serve only to generate 'swirl' in the combustion chamber for increased mixing of fuel. Review "Flap Valve" section of the VW Document "Self Study Program #826803 2.0 Liter TDI Common Rail BIN5 ULEV Engine" if you doubt me or please cite references to the contrary.
I'm still looking for your reference where the flap valves serve "only" to generate swirl in the combustion chamber and do not do what I stated.
 

n1das

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So it seems to me like about 1200 rpm (just above idle coincidentally) would make enough airflow to lift out the big drops, and @ 2000 rpm it should be like a 40mph wind tunnel inside the intercooler and water should have very little if any chance to "collect". And if you ever rev your engine to 3-4k RPM (like daily, right!!!) that should really blow through collected water, unless there are some seriously poor flow geometries in the system.

Icing from condensation on the other hand, I can see that. Ice melting after shutting down and sitting warm, making puddles down low, and then slugs of water ingested straight in on startup - I can definitely see that.

My $0.02 - thanks for reading. Typing is therapeutic and I'm a little riled up :eek:
What is your driving style like? Do you drive "softly" or do you drive it like you stole it?

What transmission does your CR TDI have? 6M or DSG? If a 6M, what RPMs do you shift at when accelerating normally and when wanting max accel?

I'm thinking regular hard runs at WOT up to 4k RPM in each gear are needed as preventive maintenance. Long highway on-ramps especially uphill ramps are good places to do this.

I've noticed with my 2010 JSW TDI is the exhaust is a lot more "steamy" during warmup compared to my 05 PD JWagen and 02 Golf (sold it in September). I suspect the source of the uber-moist air in the intercooler is exhaust via the low pressure EGR circuit when that circuit is active. It mixes with the coating of oil in the intercooler to form the peanut butter looking goop in there.

In older TDIs, the engine only had a high pressure EGR circuit, downstream of the intercooler. The CR TDIs have a high pressure AND a low pressure EGR circuit. IIRC, the low pressure EGR is introduced into the intake ahead of the intercooler. :eek: I suspect the intake will never clog up with goop but the intercooler probably will! :(

Add "drain and clean intercooler" to the preventive maintenance list! :(
 
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dieselpower2010

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My bet is that the newer cars run higher boost at cruise conditions, in part due to the lower revs. Higher pressure in intercooler brings the condensation temperature up. We need someone with a new car to go for a ride with vcds or scangauge to see what boost is.

Also, if egr is introduced pre turbo compressor suction (it does right???) that will increase relative humidity of the intake flow.

Frosting will occur without regard to air velocity. Like that lighthouse in Ohio.
If you are ok with it being a boost gauge reading my boost gauge is tapped on my intake and on the average road at 70mph with cruise set i boost about 5-8psi which holds about 2000rpm.
 
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GraniteRooster

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What is your driving style like? Do you drive "softly" or do you drive it like you stole it?

What transmission does your CR TDI have? 6M or DSG? If a 6M, what RPMs do you shift at when accelerating normally and when wanting max accel?
Thats a good thought, but not driving style related. Mine is a 6spd, its gets an italian tuneup a couple times each way on my 100 miles across NH. Bedford and Hookset tolls (traffic conditions permitting), long uphill on-ramp from RT89S in Concord to RT93S, likewise hills on RT 89, and I live on top of a hill that I regularly use to clean her out before I shut her down (after which I have a couple miles of slight downhill & neighboorhood cruising to let it cool off after WOT before shutdown.) At WOT I shift just past peak HP @ 4200-4400rpm, more regular driving I shift 3-3.5k even if not WOT just to keep the airflow up.

You simply can't work it any harder that I do without driving like a jerk on the highway or exceeding reasonable speed limits. The day my car choked and went LIMP, I left Hudson at 5pm in a freezing rain & snowstorm, and was in the left-hand lane all the way up Rt 3 through Nashua, and past Manchester in heavy PM rush hour traffic. As you know, that stretch gets bumper to bumper, Speed 70-75, and no opportunities to pass or "surge WOT" for short periods to try to melt ice. That tactic wouldn't work anyway, because 10 sec of WOT and you are past the speed limit, and 10 sec of turbo heat is not going to melt much ice if any accumulated in the intake from cruising at typical throttle openings. Then, you back off the throttle, and heat goes away and you are building ice. Aim a hairdryer at an ice cube for 10 seconds and let me know how much ice is left. My intake had about a dozen ice cubes worth of ice in it.

The days before LIMP, (Sunday the 13th & Monday the 13th) it was 54 degrees out in Nashua, so it is safe to assume my car blew itself out completely on my drive home Monday. That means whatever it choked on the next day accumulated in that 24 hour period, and most likely in the evening during my 30 minute stretch between Nashua and Manchester in heavy traffic.

Since I was in the left lane going as fast as traffic allows (and is reasonable, safe, and reasonably legal), I was maintaining the highest possible boost and temperature headed into the IC, and it still froze up under routine highway driving conditions.

No, this is not a driving style problem, this is a routine operation problem. After all, long runs on the highway are supposed to be what these cars do best.
 
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nhdoc

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Thats a good thought, but not driving style related. Mine is a 6spd, its gets an italian tuneup a couple times each way on my 100 miles across NH. Bedford and Hookset tolls (traffic conditions permitting), long uphill on-ramp from RT89S in Concord to RT93S, likewise hills on RT 89, and I live on top of a hill that I regularly use to clean her out before I shut her down (after which I have a couple miles of slight downhill & neighboorhood cruising to let it cool off after WOT before shutdown.) At WOT I shift just past peak HP @ 4200-4400rpm, more regular driving I shift 3-3.5k even if not WOT just to keep the airflow up.

You simply can't work it any harder that I do without driving like a jerk on the highway or exceeding reasonable speed limits. The day my car choked and went LIMP, I left Hudson at 5pm in a freezing rain & snowstorm, and was in the left-hand lane all the way up Rt 3 through Nashua, and past Manchester in heavy PM rush hour traffic. As you know, that stretch gets bumper to bumper, Speed 70-75, and no opportunities to pass or "surge WOT" for short periods to try to melt ice. That tactic wouldn't work anyway, because 10 sec of WOT and you are past the speed limit, and 10 sec of turbo heat is not going to melt much ice if any accumulated in the intake from cruising at typical throttle openings. Then, you back off the throttle, and heat goes away and you are building ice. Aim a hairdryer at an ice cube for 10 seconds and let me know how much ice is left. My intake had about a dozen ice cubes worth of ice in it.

The day before LIMP, (Monday the 13th) it was 45 or 50 degrees out in Nashua, so it is safe to assume my car blew itself out completely on my drive home Monday. That means whatever it choked on the next day accumulated in that 24 hour period, and most likely in the evening during my 30 minute stretch between Nashua and Manchester in heavy traffic.

Since I was in the left lane going as fast as traffic allows (and is reasonable, safe, and reasonably legal), I was maintaining the highest possible boost and temperature headed into the IC, and it still froze up under routine highway driving conditions.

No, this is not a driving style problem, this is a routine operation problem. After all, long runs on the highway are supposed to be what these cars do best.
I would not assume the stuff had formed in one day. If you look at the photos of what people clean out of that pipe it is not only water but oily slimy goop. Chances are that stuff was in there, accumulating at the low spot and as long as it didn't get so much in it that it blocked the flow it would probably not cause an issue. Then, when the conditions were ripe for additional condensation it pushed it over the level needed to choke off the pipe...at least that is the theory I would operate under. Look at this photo again:

http://forums.tdiclub.com/showpost.php?p=3221958&postcount=50

I'd actually like to know exactly what this stuff is. If this a byproduct of EGR being mixed with fresh intake air? What else could form this oily goop? Was yours oily like this or just pure water?
 
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nhdoc

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I am going to look in my IC at my 20,000 mile maintenance and if there is enough in there i think i am going to have it sent into a lab for analysis. To me it looks like emulsified oil.
I'd also be curious to know if those in warmer climates get anything at all in their IC pipe? Maybe theirs is just oil while ours in the northeast gets mixed with condensed water to form that snot.
 

Ski in NC

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I'd also be curious to know if those in warmer climates get anything at all in their IC pipe? Maybe theirs is just oil while ours in the northeast gets mixed with condensed water to form that snot.
Condensation is probably forming even in the southern cars. The trick in colder weather is the freezing. If the water stays liquid, it will blow through with the airflow with no harm. If it freezes, it accumulates.
 

El Dobro

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If/when the TSB from VW appears, I'd really like to know what they come up with.
 

GraniteRooster

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I think the oily goop is in there as a baseline, and if you have alot of humidity & condensation you get the emulsified goop that also tends to collect. Then, under the right conditions you add icing and subsequent melt and you have a bunch of water sitting on top of the goopy emulsion blocking everything.

I did not see my goop - the dealer gave me the impression is was a mix more on the watery side (water and ice), and bit of goopy emulsion mixed in. I should have asked to see it.
 

nhdoc

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I honestly don't think ANY liquid water being sucked into a diesel engine is a good thing. Diesel engines in general are much more susceptible to hydro-lock due to their high compression so a slug of water trying to push through right at high boost/rpms would be enough to cause me concerns.
 

Jack Frost

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I have just scanned the entire thread so I hope that my following comments include everything that has been said. Here are my 2 cents.

There are only two ways that I can imagine water can ending up in the intercooler:


  1. If a the car is operated when the humidity of the air is saturated (or nearly so) and then shut down followed by a drop in air temperature. Condensation will form inside the air cooler and the entire air intake system.
  2. Moisture is been injected into the intercooler either in the liquid form or if in the vapour form, at a dew point higher than the ambient air. After shut down, condensation will form.
In first case, the amount of water should not be enough to cause a problem. A teaspoon perhaps. The second case asks what is injecting water into the intercooler. I looked in the Bentley manual and cannot see any connection between the EGR and the intercooler.:confused:

In any case, the fact that air pressure inside the air intake systems is pressurized by the turbocharger I can't see as an issue as the resultant heating lowers the relative humidity and would be drying out any form of liquid water regardless of the outside humidity, or form of precipiation such as rain or snow.
 

Ski in NC

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Raising pressure by half an atmosphere (7psi boost) raises the temp, but when cooled back to near ambient in intercooler, the resultant mixture will have much higher relative humidity. Increase pressure and keep all else equal raises rh.
 

nhdoc

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Lots of strange things can happen when air is compressed, heated, expanded and cooled. It's really not a simple equation and I can certainly see conditions where ice can actually form on the inside of the entire intake system, like it can on an airplane's intake, and can choke off the flow of air just as carb icing does. Ask a pilot if this happens under many conditions that "common sense" would think impossible. I sense the volume of water being seen in the ICs is a result not of pure "condensation" but really of intake icing which melts and refreezes at the low point in the IC.
 

dieselpower2010

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Is this right? Seems awfully high for a stock car.
It did seem high to me also cause everyone i talked to before i put in the gauge said i would top out at 15psi with a spike of 17psi. But as soon as the gauge went in i took it out and i regularly go WOT and i get usually 24psi spike with about 23psi sustained. And i can promise i am completely stock.
 
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GraniteRooster

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Our cars come stock with a pretty advanced turbo - 22-24psi peak sounds right from what I've remember seeing published. I do not have a gauge on mine.

If you read the sum total of rough starts experienced by people in the NE lately, virtually all happened after long runs in cold weather, following by sitting idle in warm above freezing weather. In each case, the above-freezing start was accompanied by rough starting, rough idle, stumbling, and every now and then it seems, hydrolock. All symptoms of trying to draw too much water through the cylinders. This points straight to intake icing, as does my shutdown/LIMP experience on the highway.
 

dzcad90

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Our cars come stock with a pretty advanced turbo - 22-24psi peak sounds right from what I've remember seeing published. I do not have a gauge on mine.

If you read the sum total of rough starts experienced by people in the NE lately, virtually all happened after long runs in cold weather, following by sitting idle in warm above freezing weather. In each case, the above-freezing start was accompanied by rough starting, rough idle, stumbling, and every now and then it seems, hydrolock. All symptoms of trying to draw too much water through the cylinders. This points straight to intake icing, as does my shutdown/LIMP experience on the highway.
Can we please stop using the term "hydrolock" in this context?

Hydrolock refers to a very specific type of engine damage caused by an incompressible liquid being present in the cylinder and causing catastrophic engine damage.
 

GraniteRooster

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Can we please stop using the term "hydrolock" in this context?

Hydrolock refers to a very specific type of engine damage caused by an incompressible liquid being present in the cylinder and causing catastrophic engine damage.
No, we cannot. I am referring to exactly the definition you provide above. A gentleman in Wisconsin is already having his engine replaced by VW due to Hydrolock caused by this issue. Diagnosed by VW dealer as HYDROLOCK. See here:

http://forums.tdiclub.com/showthread.php?t=301481&highlight=hydrolock

It takes less than an ounce of water to hydrolock a cylinder on this engine. If multiple CUPS of water are in the IC during startup - what do you think is going to happen?

When people with rough start symptoms crank their engine and it wont turnover the first time - that engine is struggling against water and or frozen ice. When that gets sucked up into the cylinder - goodbye. When it cranks the second or third time, if you are lucky most of it gets sucked through without doing damage, thus all the stumbling, rough idle, etc. for the first 30-60 seconds. If you are not lucky - you hydrolock. All of us are one bad situation away from a trashed engine.

Anyone who has had multiple nasty rough starts would probably be wise to have their compression checked - I plan to. My car seems to run OK, but a couple of the starts really were not pretty.
 
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mysql

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Highest I've ever seen or heard of (in a Mazda race engine) was ~10:1, which is I guess in par for a regular 4 stroke street gas engine, but the apex seals were replaced after each race.
But try parking an RX/3 in first gear on a hill and leave the e-bake off and see what happens (ask me how I know this) :D
The RX-8 is 10:1 as well.

You cannot hydrolock a rotary. Which is why one of the carbon removal methods commonly used is a gallon of distilled water directly to a vacuum tube behind the throttle body. You will get stumbling as you do this, just keep the revs up. If you suck in too much water, it'll die. Start it up and try again!

Also common to remove the spark plugs, and inject seafoam directly into the engine, and hand crank the engine over to the next rotor face and repeat.
 

dzcad90

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No, we cannot. I am referring to exactly the definition you provide above. A gentleman in Wisconsin is already having his engine replaced by VW due to Hydrolock caused by this issue. Diagnosed by VW dealer as HYDROLOCK. See here:

http://forums.tdiclub.com/showthread.php?t=301481&highlight=hydrolock

It takes less than an ounce of water to hydrolock a cylinder on this engine. If multiple CUPS of water are in the IC during startup - what do you think is going to happen?

When people with rough start symptoms crank their engine and it wont turnover the first time - that engine is struggling against water and or frozen ice. When that gets sucked up into the cylinder - goodbye. When it cranks the second or third time, if you are lucky most of it gets sucked through without doing damage, thus all the stumbling, rough idle, etc. for the first 30-60 seconds. If you are not lucky - you hydrolock. All of us are one bad situation away from a trashed engine.

Anyone who has had multiple nasty rough starts would probably be wise to have their compression checked - I plan to. My car seems to run OK, but a couple of the starts really were not pretty.
One case of confirmed hydrolock is not "every now and then." The suggestion that every car that has had a cold rough start go get a compression test is ludicrous. My car had a rough cold start last winter and 20K miles ago. Have I been driving around with bent rods for the last year? :eek:

This is the third winter season that the CR has been available in this market and we have one reported case of hydrolock - this makes it the exception rather than the rule at this time. The suggestion that hydrolock is a likely happening is simply spreading FUD for the sake of causing undue concern in the minds of others. Until we get some actual data gathered and more confirmed cases of excessive sludge in intercoolers causing actual damage that can be quantified in some way other than an inconvenience in a rough cold start, the alarmist nature of this thread does no service to anyone.
 

IndigoBlueWagon

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This doesn't appear to be an isolated case. How many people on this thread have had symptoms, and have found significant moisture in their IC system? 4? 5? And there are at least two other threads with the OPs mentioning this problem, at least one that has destroyed his engine. Just found another today from a CT driver that had the dealer drain significant water out of the IC system. It does appear that this condition can be duplicated. The CT driver thought gelled fuel caused the rough start, and eventually the no-start. I wonder how many more people who have water issues think it's gelled fuel.

There are lots of issues here that start as isolated cases. Balance shaft issues, BEW or '01 ALH cam wear, lift pump failures--you get the idea.
 
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