***************************************************************************************
UPDATE 01/18/12
GraniteRooster's Frozen Charge Air Cooler (Intercooler) FAQ / Problem Summary
In an attempt to provide to most relevant details to the forum in summary format, I have compiled the following brief of the issues. This is multifaceted problem whose unresolved issues and discussion runs much deeper than this summary - I'd encourage folks to read the thread in detail for best understanding. At 1900+ posts and counting, you'll need a cup of coffee/tea and comfy chair
Problem
When driving in winter conditions (below ~20-25°F), external airflow over the air-air intercooler (IC) is cold enough to cause internal ice buildup in the IC and outlet charge hose assembly. Ice buildup may lead to a variety of operational difficulties including restricted intake, reduced power, LIMP mode, engine stumbling, melt water or ice ingestion, and catastrophic engine damage.
Affected Engines
All 2.0L CR TDI engines (CJAA/CBEA) installed in all 2009-2012 model year Jetta TDI, Jetta Sportwagen TDI, and Golf TDI vehicles. Vehicles in both US and Canada are affected.
Occurrence
Ice buildup occurs while driving in cold winter conditions, typically below ~20-25°F. Melt water and ice ingestion may be experienced on subsequent engine start if the car is allowed to thaw while parked (such as in a warm garage, or warm parking lot above freezing temperatures).
Causes
This is a thermodynamic phenomenon caused by condensation and subsequent freezing or direct vapor deposition of water vapor as the turbo-compressed charge air is cooled through the IC and outlet charge hose assembly. Two main aspects of engine design contribute to the problem:
- Low-pressure EGR is used to control NOx formation for emissions compliance, however, this recirculates water vapor rich exhaust back to the turbo and IC.
- The IC design on these vehicles is very efficient, providing good heat transfer and economy (and good ice formation under proper conditions)
Symptoms
Ice
- Restricted Intake & Reduced Power
- LIMP Mode (flashing MIL’s, “Service Now” message)
- Engine will not turn over (complete ice obstruction of intake)
- Catastrophic engine damage (ice chip ingestion)
Water
- Engine will not turn over, "dead battery" starter action (due to hydraulic resistance in cylinder)
- Starter/electrical fires (due to starter overheating during attempts to start locked engine)
- Engine will turn over slow / not start (drowning)
- Engine will misfire, stumble, and run roughly upon starting (water ingestion)
- Engine will misfire, stumble and run roughly upon acceleration (water ingestion)
- Catastrophic engine damage (water ingestion – hydrolock)
Solutions
VW has issued Technical Service Bulletin (TSB)
TSB # 21 11 06 / 2025464 Frozen Charge Air Cooler. The kit may be installed by dealers on documented vehicles under original 36k warranty. Customers outside 36k warranty have often been denied installation under 60k powertrain warranty.
A (basically ineffective placebo) temporary solution implemented by VW involves removal of the forward facing cold air intake "snorkle" so that the airbox draws air from the engine bay, which allegedly may be warmer. In practice, TDIClub member testing has shown this modification to make insignificant changes to intake air temperatures, and is therefore ineffective.
What to Do - Frozen IC happened to me!
If the car won't start after one attempt, or stumbles and dies after an initial attempt,
***STOP!*** You have some decision making to do...
Further attempts to start the engine may (or may not) cause damage from minor to catastrophic. Depending on the amount of water in the intake and engine, damage may occur to pistons, connecting rods, glow plugs, injectors, head gaskets, etc. due to hydraulic lock. There is also risk of starter and electrical system damage from repeated start attempts against a locked engine. You will need to choose:
- Service the car (preferred) , or
- Attempt to start the engine and get where you are going (risky)
The best solution is to clear the intake and engine of water and ice before starting. However, it seems the engines are often able to pass melt water with undetectable or no damage. The preferred actions are:
- Option 1: If under 36k warranty period, have the car towed to a VW dealer by VWoA to have the water and ice drained out and problem documented for installation of Technical Service Bulletin (TSB) TSB # 21 11 06 / 2025464 Frozen Charge Air Cooler. Dealers typically will require this hands-on service and documentation to gain required approval from VWoA for installation of the IC TSB under warranty.
- Option 2: Elevate the front of the car on jackstands, remove belly pan and lower IC outlet charge hose, remove water and ice from assembly. Reassemble and drive. This option will not be convenient for a typical owner in most typical situations, given need for jacks, stands, tools, light, etc. plus safe environment and time to complete the repair.
- Option 3: Have vehicle towed to appropriate repair facility for removal of water and ice from the IC assembly
Owners should report problems to their VW dealer and
VWoA (1-800-822-8987) (or VWoC, etc.) as they occur. VWoA has the ultimate say in warranty installation of IC Kits; they rely on dealers to be gatekeepers on diagnosis, therefore dissatisfied owners having difficulty with installation approval should increase negotiations directly with both dealer and VWoA. Owners with safety concerns due to this issue should contact
NHTSA and report their concerns.
***************************************************************************************
UPDATE 01/17/12
Click hyperlink for .PDF copy of TSB # 21 11 06 / 2025464
(Credit 740GLE Post #1352)
***************************************************************************************
UPDATE 09/14/11
TSB # 21 11 01 / 2025464 dated May 24, 2011 has been super-ceded by TSB # 21 11 02 / 2025464 dated June 14, 2011 and most recently,
TSB # 21 11 06 / 2025464 dated September 6, 2011. The latest TSB referenced updates to warranty table and labor information. It may be helpful to reference the latest TSB when requesting warranty work.
(Credit Aerox Post #1003)
***************************************************************************************
UPDATE 6/2011
There is now a TSB with a fix for this issue. TSB # 21 11 01 / 2025464 dated May 24, 2011, titled "Frozen Charge Air Cooler – Engine Will Not Start". It calls for installing a
1K0-198-803-B Cold Weather Intercooler Kit.
The kit includes:
- New Intercooler (IC) with internal vacuum-actuated flap valve
- Vacuum Sensor
- Intake Elbow with Temperature Probe & Vacuum Actuator
- required plumbing
Installation requires 3-4 hours labor and corresponding ECU software update. This kit was installed on my car by VW on 07/06/2011. Here are pictures of the kit installed on my '10 JSW, as seen from the front of the engine compartment. The post-IC intake charge temperature/vacuum actuator are circled in red. The rest of the kit is not easily viewed without removing the engine belly pan, etc.
EDIT 03/07/2012: Member UberVW_TDI posted nice pictures of the components of the kit in
Post 792.
Integrated Temperature Sensor and Vacuum Switch / Blending Valve mounted on Elbow
Intercooler with vacuum actuated diverter valve
03G-906-051-K (VACUUM SENSOR)
EDIT 03/07/2012: Member PAJettaTDI posted good photos of his installation in his
photo thread.
***************************************************************************************
ORIGINAL POST 12-17-2010
**I posted this at the end of the "
Cold Start/Scare" thread in the MK5 forum - but thought I would post here in Mk6 JSW as well for the benefit of MK6 owners who do not frequent the MK5 forum... I hope that is OK.**
After a longtime lurking I have something to say and its not good - my car has been having significant icing problems as well.
I commute 100 miles each way from Northern NH to Southern NH 4 times a week. I leave at 5am and return at 5pm. Obviously NH is subject to freeze thaw cycles and we have been having some very rainy, humid conditions this November/Early December.
I have had rough starts with symptoms of water being drawn through the engine 4-5 times in the last 3 weeks. I have had the engine not turn over once.... paused 5-10 sec, checked myself, tried again, and cranked but caught rough and stumbled for 45-60sec...., and then again once pulling out of parking lot, engine RPM's (and airflow) rising, more stumble.
Then, Tuesday Dec 14th driving home, left South NH in 27 F degrees, rain, snow mix and temperature falling rapidly. 25 minutes into the drive, precip has transitioned to mostly snow, and temperature now 14 F degrees and still falling. 72mph in left lane, power cuts, Service NOW message, Glow Plug lights flashing. Finished 70 mile drive home with engine in LIMP mode and 10 degree external temperatures, wondering if my HPFP was expired. I was low on fuel, so left engine idling in LIMP and filled up with my favorite B5 before continuing home and shut it off. Read most of
this thread... holy cow this is not good.
Next morning, 8deg, car fires up, no CEL's, drive 100 miles to dealer and drop it off. They let it sit till lunch outside in freezing temps. Bring it into shop, they drained almost a cup of water and ice out of the intercooler lines.
This is major spooky as I have already had one start that was "hydro-locked", but I didn;t know what was going on at this time so I forced it and it started horrible. I am real concerned about major long term engine damage from regular ingestion of big slugs of water caused by this icing/melt problem. This car is 10 months old with 33,000 miles, driven very regular route, broken in well and driven accordingly, 2 out of 3 fillups with B5 and the rest straight ULSD always from the same two stations, so the average bio-concentration in the tank is is usually B2-B4..... I intended to keep this car a long time, but having it ice up a couple times a week for several months of the year is just not going to work.
Dealer considers car fixed until it throws another code... and it doesn't throw a code when it hydrolocks or or rough starts. I question how many more times this can happen before I have bent or broken rods and worse.
Thanks to all for very cool and informative forum here - I have learned a lot and enjoyed my TDI very much until now. Thought I would let you all know of another iced up intercooler.
I am also starting a case with VWoA - the more the merrier.
