Like a virgin

New Mickey

The user formerly known as mickey
Joined
Jun 6, 2017
Location
Utah
TDI
2015 Passat
Deja vu! I can remember exploring under the hood of the Evil Beetle trying to figure out what all the weird lumpy bits were. Now I'm going through it again. It's kind of fun!

First of all, I figured out how to take the plastic cover off the engine. (No more screws. Rubber grommets.) Then I quickly found the fuel filter. But it took me a minute to figure out what the aluminum box was....AIR TO WATER INTERCOOLER! Who knew? (Not me.)

Questions:

1. Where did they hide the oil filter?

2. Has anyone used a Topsider to suck out the oil from a 2.0 CR TDI? Can a tube reach all the way down to the bottom of the sump?

3. What's the Flapper Valve for? Does it involve Betty Boop?

And an important conclusion: I'm too old and non-bendy to work on this thing, so I hope it's reliable. The under-hood environment is tighter than a 9 year-old nun. Does NOT look like fun to work on.

-mickey
 

jrm

Veteran Member
Joined
Jul 24, 2013
Location
Oregon
TDI
2013 Passat SE with nav (totaled)
I also come from the pre TDI Era as well, grew up swapping .75 5th gears into 1.6 rabbits and golf's to get that sweet 55+ MPG. The NMS Passat is a great ride, not as tough as our old 1.9's and such but overall quite good- you will have fun learning all about it- even the glow plugs can read real time combustion pressures! The thing is super smart, it has both intake and exhaust butterfly valves so it coasts better than a gasser- until you touch the brakes- as soon as the brake lights activate the ECM knows you want braking, it will drop a gear and open the intake and exhaust valves giving you the classic diesel compression braking as needed, just a sweet ride and once you understand what causes what (brake lights) you can really hyper mile these things!
 
Last edited:

New Mickey

The user formerly known as mickey
Joined
Jun 6, 2017
Location
Utah
TDI
2015 Passat
I've noticed the DSG drops a gear when the car's speed exceeds what you've set with the cruise control whether you brake or not. Actually I wish it was more aggressive about holding the speed down. My much-lamented 2015 F-15 was brilliant that way. It would drop as many gears as necessary to maintain the set speed, but if I wanted to "hypermile" I had but to cancel the cruise control and it would stay in top gear.

The Passat works basically the same way, but never seems to drop more than a single gear to maintain your set speed. I find myself using the Tiptronic slot for mountain descents. There's also a huge step in gear ratio between 2nd and 3rd so I've learned not to drop all the way to 2nd unless I'm down to 2000 RPMs or less in 3rd.

Diesels don't "compression brake" worth a wet slap, because they have no throttle valves. The energy used to compress the air pushes the piston back down again, so there is no net braking effect except for internal friction. That's why "Jake brakes" and other schemes are needed.

I didn't know the 2.0 CR did that. I need to study up.

-mickey
 

BKmetz

Administrator, Member #10
Staff member
Joined
Sep 25, 1997
Location
Illinois
TDI
2015 Passat, titanium beige, 6MT
The exhaust flapper is active during start ups and soot trap regens.

When you start the car up and drive off, within the first 1 to 3 miles the flapper will restrict the exhaust flow to raise EGT. This is to warm up the catalyst systems ASAP. Usual EGT will be around 1100F to get the DPF temp to around ~800F. This warm up mode lasts around 1 minute. You have to be in 3rd gear or higher for the ECU to go into catalyst warm-up mode

When the soot trap sensors detect a high differential the ECU will call for a soot trap regen. The flapper will again restrict exhaust flow to get the EGT high enough to burn off the soot. Fuel injection is retarded to allow raw fuel into the exhaust and get the DPF very hot very fast. During uninterrupted highway driving a typical regen will last around 10 miles. During stop & go city driving a typical regen lasts around 6 miles. The shorter regen time does not mean a better regen. It means the ECU detected the interruptions and called it quits early when the DPF regen was close enough. The more highway driving with uninterrupted regens means fewer regens. Fewer regens means less ash build up in the DPF and it will last longer. During a regen the EGT will drift around from 950F to 1350F and the DPF temps will get as high as 1150F.

There are 3 ways to monitor all this. Methods listed from the easiest/cheapest to the most involved/expensive.

1. get a OBD-II Bluetooth dongle and download an OBD-II app for your smart phone. Plug the dongle into the OBD-II port and set up your phone bluetooth and app. While this is the cheapest and easiest to use, the downside is that it ties up your phone. For constant monitoring some owners get an old obsolete smart phone and leave it plugged in all the time. A bluetooth OBD-II dongle is usually less than $20. Here is a thread on OBD-II dongles. http://forums.tdiclub.com/showthread.php?t=479014

2. Buy a Scangauge-II. Prices are all over the place from $100 to $150 so watch for a sale. Here is the link for setting up the Scangauge-II. http://forums.tdiclub.com/showthread.php?t=360498

3. Get a VCDS cable (formally known as VAGCOM). The bad; expensive, lots of reading to learn how to use it. The good; use for diagnosing just about anything, data-logging, can be used with a cheap windows laptop or tablet. With VCDS you can force a regen at your convenience. Convenience meaning you are monitoring the DPF differential and when you are getting close you can force a regen when you know you have at least 10 miles of steady driving, like on the highway on cruise control. The ODB Scanner forum is your friend here.

Some other trivia for you: The 2012-2014 Passat TDIs use the CRKA engine. The 2015 Passat TDI uses the CVCA engine. Not much interchanges between the engines. On the CVCA the intercooler and intake manifold are one part. On the older CRKA they are two separate parts.

The CRKA and the CVCA catalyst systems are completely different designs although they do exactly the same thing.

The oil filter on the CVCA is a canister type facing down along side the engine, similar to the 2.5L gasser. You're going to have to get under the engine to change the oil filter. The oil filter on the CRKA is similar to the old ALH engines, filter housing facing up. Lots of members use a Topsider.

:)
 
Last edited:

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
La Conner, WA
TDI
... None :S
I'm not sure about the 15s, but the 12-14s can be *very* tricky to use a topsider on due to how the oil pan is arranged. It's easy for the suction tube to get stuck in a "redirection" tube mounted below the balance shaft. Use only a small, metal reinforced tube!

What flapper are you talking about? The intake throttle? Exhaust throttle? Warm up flap on the airbox?
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
I've noticed the DSG drops a gear when the car's speed exceeds what you've set with the cruise control whether you brake or not. Actually I wish it was more aggressive about holding the speed down. My much-lamented 2015 F-15 was brilliant that way. It would drop as many gears as necessary to maintain the set speed, but if I wanted to "hypermile" I had but to cancel the cruise control and it would stay in top gear.

The Passat works basically the same way, but never seems to drop more than a single gear to maintain your set speed. I find myself using the Tiptronic slot for mountain descents. There's also a huge step in gear ratio between 2nd and 3rd so I've learned not to drop all the way to 2nd unless I'm down to 2000 RPMs or less in 3rd.

Diesels don't "compression brake" worth a wet slap, because they have no throttle valves. The energy used to compress the air pushes the piston back down again, so there is no net braking effect except for internal friction. That's why "Jake brakes" and other schemes are needed.

I didn't know the 2.0 CR did that. I need to study up.

-mickey
You should drive a 2012-2014 DSG passat, its a different transmission gearing as well as control unit. It loves to down shift on hills and you'll be in 3rd gear doing 55-60 down a hill if you keep a light foot on the brake, I found it didn't really slow you down and just seemed to make more noise.

I haven't driven our '15 enough but did notice its not as jumpy to downshift.
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
I'm not sure about the 15s, but the 12-14s can be *very* tricky to use a topsider on due to how the oil pan is arranged. It's easy for the suction tube to get stuck in a "redirection" tube mounted below the balance shaft. Use only a small, metal reinforced tube!

What flapper are you talking about? The intake throttle? Exhaust throttle? Warm up flap on the airbox?

Also the oil filter is accessed from under the car, and it will dribble so catch can is needed. So if you're under there, is there a point to the top side? Maybe avoid any additional spills?
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Yes, you'll need to get under the car anyway. I gently move a harness off of its stay and position aside to make for less mess. The longer you can let the drain plug drain the better, too. Not sure which filter is better, to be honest. The CKRA is worse than the CBEA/CJAA in that it is tighter in there and it uses a plastic housing instead of aluminum. I suspect that could be a problem in years to come.

Of course by then there will be so few CKRA cars left on the road, we won't notice. :(
 

KERMA

Vendor , w/Business number
Joined
Sep 23, 2001
Location
here
TDI
99 beetle and 04 jetta
Also, the Polar FIS works with the passats. Super cool, turns your MFA into gages.

VCDS needs to be one of the hex+can or newer ones that use the "smart dongle". The older cables won't work.

Interesting what BK said about regens but FWIW those cars base their regens on the internal model not the measured D/P.

Mickey come by sometime, I can give you a guided tour of your car's stuff if you want. And yes your car does have throttle(s).
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
Yes, you'll need to get under the car anyway. I gently move a harness off of its stay and position aside to make for less mess. The longer you can let the drain plug drain the better, too. Not sure which filter is better, to be honest. The CKRA is worse than the CBEA/CJAA in that it is tighter in there and it uses a plastic housing instead of aluminum. I suspect that could be a problem in years to come.
Of course by then there will be so few CKRA cars left on the road, we won't notice. :(

I hated pulling the oil filter from the CKRA, the wire loom could only be moved so far out of the way to wiggle the filter/cap. Eventually i loosened the HP egr tube enough to gain access.

As for the CKRA being on the road I hope the "fix" will provide enough incentive for VWoA to resell them and keep them going.

I'd love to snag a '12 Passat SE manual as a beater car to keep the miles off the Alltrack.

In a year or so I'll let you know how I feel about the new CRVA
 

Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
I hated pulling the oil filter from the CKRA, the wire loom could only be moved so far out of the way to wiggle the filter/cap. Eventually i loosened the HP egr tube enough to gain access.
<snip>
These cars seem to come with things ever so slightly different in a way that allows the filter & cap to be "angled" to the right and forward out of the housing. We got lucky with our '13 Passat, as all it takes is to remove those three T30 screws on top, set the plastic bracket aside and ease that tube toward the front of the car to then maneuver the cap & old filter up and out. There is no excuse for any of it, of course. It wouldn't have required any genius engineering to make it an easy matter to do the change. But the engineers who designed it didn't necessarily plan on actually doing any changes themselves. Access to that DSG filter is a different matter, but at least it only has to be done every 40K....
 

roni024

Veteran Member
Joined
Mar 31, 2007
Location
Syracuse, NY
TDI
2015 Passat TDI SEL DSG
FWIW, on my 2013 Passat the DSG filter is accessed by removing the air-box and snorkel (disassembly of air box not required), battery, and battery tray. 24mm socket gets the filter cap off. I just changed my fluid Friday so it's fresh in my mind.
 

Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
FWIW, on my 2013 Passat the DSG filter is accessed by removing the air-box and snorkel (disassembly of air box not required), battery, and battery tray. 24mm socket gets the filter cap off. I just changed my fluid Friday so it's fresh in my mind.
Yeah, that's pretty much what I did for the 40K a year ago March. I laid it all out in this: http://forums.tdiclub.com/showthread.php?t=457823
I found the removal of the battery tray to be a bit challenging, although not as much as trying to replace the battery clamp. All of this doesn't mean it couldn't be engineered to make the DSG service easier, but I certainly concede that probably would be harder than just creating a smidge more room to get the CKRA engine oil filter cap up & out more easily.
 

BKmetz

Administrator, Member #10
Staff member
Joined
Sep 25, 1997
Location
Illinois
TDI
2015 Passat, titanium beige, 6MT
Interesting what BK said about regens but FWIW those cars base their regens on the internal model not the measured D/P.
I've watched dozens of regens on my Scangauge and if there is one thing that is consistent, it's how the ECU determines when a regen is needed is completely inconsistent. I've had as many as 3 short regens within 100 miles of each other and I've gone almost 2 tanks of fuel (~1600 miles) between regens. I'm sure there are several parameters the ECU is looking at. The only common denominator that I can think of is how much soot has collected in the DPF. 'internal model' is an interesting term. Can you expand on that?

Yes, you'll need to get under the car anyway. I gently move a harness off of its stay and position aside to make for less mess. The longer you can let the drain plug drain the better, too. Not sure which filter is better, to be honest. won't notice.
I hated pulling the oil filter from the CKRA, the wire loom could only be moved so far out of the way to wiggle the filter/cap. Eventually i loosened the HP egr tube enough to gain access.
I pack some paper towels around the oil filter and wire loom. Then I unscrew the cap and pop it up, not off, and let the oil drain down a while before I remove the oil filter. A blast of brake cleaner takes care of any mess I made when I'm done. It took me a while but I figured out the perfect angle to drop the clean filter back into the filter housing. That plastic center piece that is part of the cap and sticks out a bit from below the actual filter has to be perfectly aimed to hit the hole in the filter housing and there is no room to wiggle it around.

All in all, I would rather change oil in a CRKA over a 1Z or AHU. No possible way to change one of them without making a mess.

:)
 

KERMA

Vendor , w/Business number
Joined
Sep 23, 2001
Location
here
TDI
99 beetle and 04 jetta
'internal model' is an interesting term. Can you expand on that?
A little.

In the interests of brevity (and competition considerations) let's just say this. There is a simulated (calculated) soot number and a measured soot number. You can see these in adv meas values in vcds. The measured number comes from the d/p sensor. The calculated number is based on a complicated internal soot simulation model. There are a series of conditions (temp, pressure, throttle, etc) and software application switches that decide when each holds sway. The details of that mechanism are not important for this discussion. But in the CR ecus I've seen it appears that the measured number is pretty much intentionally "turned off" for purposes of deciding when regen should occur. You can see this yourself... If you ever monitor both measured and calculated, you will likely see the calculated generally keeps going up and up at some rate, while measured can fluctuate up and down pretty notably (with passive regen for instance). In our GSW the regen happens pretty predictably when calculated soot reaches ~24 g. (earlier cars the number was lower like 18g) Measured soot could really be anything when regen happens. (unless it gets too high) But the calculated will be like clockwork. The soot simulation model is fairly conservative compared to what physical soot is under most conditions, and the model doesn't appear to consider passive regen effects in any significant way. Regens other than the DPF *are* considered in the model though, and these may not be noticed if you are only monitoring pre-turbine EGT.

There is also some conditions of engine run time, miles since last regen, fuel used since last regen, and a couple of others, but those are switched off in the ecu I have checked. So its pretty much all on the soot simulation model to trigger regen.

hope that helps
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
KERMA, I have to ask, since you seem so familiar with the EDC17's internal workings as applied to the VAG CR engine, did you or any of the other tuners notice the "cheat" before the cat was out of the bag? Just curious. Seems like it would have been obvious to those that know what they are looking at.

Related: do you know anything about Mercedes-Benz' SCR logic? As in, how would a "low DEF usage" DTC be gathered? I assume SCR is essentially the same across brands.
 

KERMA

Vendor , w/Business number
Joined
Sep 23, 2001
Location
here
TDI
99 beetle and 04 jetta
Not familiar with the MB. Not enough time in the day. I am hyper focused on VW TDI and always drilling down deeper.

I think I posted something in the mega threads about how I believed the cheat worked. It was somewhat obvious to find once it was known to be there. It doesn't really change what a tuner does, just a matter of intellectual curiosity for me. Those ecu are pretty complicated as it is, for example more than 20 turbo boost maps in a CJAA for the various operating mode states. A few regen states, Several preinjection states, high altitude versions of each, etc and so forth. Even the very rudimentary "shallow" tunes out there should cover all those operating modes anyway. It's kind of like doing 20 tunes for each ecu if it's done right. So "typical" tuning method is not terribly affected whether the cheat is there or not.

Interesting to note that the "fix" sw versions have notably fewer maps for everything. because the "alternate mode" maps are just gone. This is remarkable, because typically Bosch keeps unused functions in the ecu, but just turns it off if they have to, with a vestigal map as a place holder or something like that. But this is different- it is completely gone. It's quite a remarkable departure from what was the normal practice.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Intellectual curiosity is a good way to put it, and I am in the same mode with that. So how does SCR equipped VAG engines work? Are the pre and post NOx sensors calculating DEF usage by the reduced value across the substrate in the deNox catalyst? They do not show "real" DEF tank levels, so it cannot calculate it that way.

I have had a few CATA 3.0L engines with failed deNox catalyst faults.
 

New Mickey

The user formerly known as mickey
Joined
Jun 6, 2017
Location
Utah
TDI
2015 Passat
Also, the Polar FIS works with the passats. Super cool, turns your MFA into gages.

VCDS needs to be one of the hex+can or newer ones that use the "smart dongle". The older cables won't work.

Interesting what BK said about regens but FWIW those cars base their regens on the internal model not the measured D/P.

Mickey come by sometime, I can give you a guided tour of your car's stuff if you want. And yes your car does have throttle(s).
I assume by "come by" you mean "drive to Colorado"? Which I'm not against doing, just for the road trip. I'd rather wait until I have the money for a DSG reflash.

-mickey
 

New Mickey

The user formerly known as mickey
Joined
Jun 6, 2017
Location
Utah
TDI
2015 Passat
Not familiar with the MB. Not enough time in the day. I am hyper focused on VW TDI and always drilling down deeper.

I think I posted something in the mega threads about how I believed the cheat worked. It was somewhat obvious to find once it was known to be there. It doesn't really change what a tuner does, just a matter of intellectual curiosity for me. Those ecu are pretty complicated as it is, for example more than 20 turbo boost maps in a CJAA for the various operating mode states. A few regen states, Several preinjection states, high altitude versions of each, etc and so forth. Even the very rudimentary "shallow" tunes out there should cover all those operating modes anyway. It's kind of like doing 20 tunes for each ecu if it's done right. So "typical" tuning method is not terribly affected whether the cheat is there or not.

Interesting to note that the "fix" sw versions have notably fewer maps for everything. because the "alternate mode" maps are just gone. This is remarkable, because typically Bosch keeps unused functions in the ecu, but just turns it off if they have to, with a vestigal map as a place holder or something like that. But this is different- it is completely gone. It's quite a remarkable departure from what was the normal practice.
I think they got rid of them because otherwise it would be like turning Treblinka into a Bed 'n Breakfast instead of bulldozing it. They wanted no vestige of the atrocity to remain.

-mickey
 

New Mickey

The user formerly known as mickey
Joined
Jun 6, 2017
Location
Utah
TDI
2015 Passat
Messy oil changes.....just when I thought the world was catching up to the TDI. Evil Beetle was the first zero-mess car I ever had. Most recently my 2015 F-150 had a vertical, cartridge-type filter inside a housing, just like the ALH TDI. And the oil drain plug is plastic, with two O-rings to seal it, in a plastic oil pan. You can pull the plug with your FINGERS by squeezing the locking tabs, yet it's pretty much impossible for it work lose in normal operation. No stripped or seized threads, ever. Just put new O-rings on it once in a while.

And now....back to the Stone Age. Oh well. Can't win 'em all.

-mickey
 

KERMA

Vendor , w/Business number
Joined
Sep 23, 2001
Location
here
TDI
99 beetle and 04 jetta
I assume by "come by" you mean "drive to Colorado"? Which I'm not against doing, just for the road trip. I'd rather wait until I have the money for a DSG reflash.
-mickey
No, still in tooele at the same place
 

KERMA

Vendor , w/Business number
Joined
Sep 23, 2001
Location
here
TDI
99 beetle and 04 jetta
Intellectual curiosity is a good way to put it, and I am in the same mode with that. So how does SCR equipped VAG engines work? Are the pre and post NOx sensors calculating DEF usage by the reduced value across the substrate in the deNox catalyst? They do not show "real" DEF tank levels, so it cannot calculate it that way.
I have had a few CATA 3.0L engines with failed deNox catalyst faults.
it's complicated. Mostly it's on a feedback loop using the nox sensor(s) but with a few backup modes for various situations. The front and rear lambda sensors come into play along with our good friend the internal models. The system(s) can be configured any number of ways based on various things for each engine model and even different software versions.

We can discuss a bit off the forums if you wish. (email not PM please) I'd be interested to hear about the faults because I'll bet there's a pretty straightforward fix. I would need to know the SW version to be able to take a peek at how things are set up for each of the cars in question.
 

Locoelectrician

Veteran Member
Joined
Jan 10, 2015
Location
Ohio
TDI
2015 Passat TDI SEL, 2015 Golf SEL Sportwagen, 2005 Jetta TDI, John Deere 355D
I had a 13 and now have a 15 Passat and have watched EVERY regen each car has done.

Put 90k miles on the 13 and the regents were much more predictable. About every 250 miles and would last about 20 minutes. The DPF warmup cycle was much more obvious and extreme. Never saw a regen before 150 degrees coolant temp. That car also had EXCELLENT engine braking that I would use every day on off ramps.

The 15 does regens whenever it wants and they last for muck more various times. I’ve seen them start as low as 135 degrees coolant temp. It’s summer and the car is new, but I haven’t noticed the DPF warmup cycle nearly at all. Maybe weather related, maybe not as violent, but it’s more noticeable in winter so I’ll pay more attention then. This car has basically ZERO engine braking. Downshifting basically just results in more noise and on hills that the 13 would slow with downshifting, this car will continue to accelerate and the rpms will just climb. Really wish I could get the old engine braking back, especially since I put paddle shifters in.

Really interested in the polar setup, but would like to talk to someone outside of this thread about it. I have a few questions and requirements that would need to be met that are not obvious from the website.
 

jrm

Veteran Member
Joined
Jul 24, 2013
Location
Oregon
TDI
2013 Passat SE with nav (totaled)
I had a 13 and now have a 15 Passat and have watched EVERY regen each car has done.

Put 90k miles on the 13 and the regents were much more predictable. About every 250 miles and would last about 20 minutes. The DPF warmup cycle was much more obvious and extreme. Never saw a regen before 150 degrees coolant temp. That car also had EXCELLENT engine braking that I would use every day on off ramps.

The 15 does regens whenever it wants and they last for muck more various times. I’ve seen them start as low as 135 degrees coolant temp. It’s summer and the car is new, but I haven’t noticed the DPF warmup cycle nearly at all. Maybe weather related, maybe not as violent, but it’s more noticeable in winter so I’ll pay more attention then. This car has basically ZERO engine braking. Downshifting basically just results in more noise and on hills that the 13 would slow with downshifting, this car will continue to accelerate and the rpms will just climb. Really wish I could get the old engine braking back, especially since I put paddle shifters in.

Really interested in the polar setup, but would like to talk to someone outside of this thread about it. I have a few questions and requirements that would need to be met that are not obvious from the website.
My 2013 with the fix software now acts like your 15, regen's all over the board- sometimes 2 in one drive- kinda a hot (no pun) mess with the fans running full tote after every shutdown regen or not. Downshifting rev's the crap out of the engine but not as much braking.
 
Top