15 Jetta SE MT6 Purchase

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
New member here. Might be purchasing a Jetta for the wife. Coming from 17 Explorer and trying to get the car payment in half and get a nice healthy bump in fuel economy. Realized that we really didn't need the extra room after all. Going with the MT as I plan passing this down to my daughter in a few years if I can keep it running that long and I really want her to learn to drive a stick. Hoping I am not making a big mistake by going with a diesel. Any advice on devices for pulling codes and running diagnostic tests would be awesome. Also, where is the best place to buy parts? Thanks in advance for any help!

Justin
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
This may sound like a stupid question, but has anyone just purchased another ECM, loaded the original factory tunes on it and then ran that in place of the original ECM? I guess there must be some other way that the car tracks the mileage so that the ECM and whatever have to match or a red flag would be raised if you swapped back to the original ECM for issues covered under warranty. Sorry for the dumb question, but I would love to find a way to run the original tuning and still be eligible for the warranty.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
First, welcome to the TDI world! I think the '15 EA288 engine is the best of VW's common rail diesels. And although the MKVI Jetta was originally built to keep costs down, by 2015 most of the equipment and materials quality you'd expect are back in the car. I think you'll like it.

Regarding swapping ECUs, with older VWs it using another ECU was as easy as getting one with the same part number (essential) and having a tuner delete the immobilizer. I'm not sure it's that easy any longer, as ECU encryption and coding is far more sophisticated than 15 years ago.

Lots of people here are apprehensive about losing warranty coverage by tuning the car. If you're interested in keeping the car largely stock I don't think there's a big downside to running the fixed tune instead of the original. Only significant difference I've noticed is less power on takeoff because of changes to the fueling maps. This is, I believe, more noticeable with the manual cars than automatics.

An aftermarket tune fixes that, but also may jeopardize your warranty.
 

bizzle

Veteran Member
Joined
May 21, 2013
Location
Southern California
TDI
2015 GSW SEL (totaled), 2013 Touareg Executive
The best device for diagnostics is a Vag-Com using VCDS: http://www.ross-tech.com/vag-com/ You buy the device and the software (and all future updates) is free. You can buy a used one from someone and you'll still get free software but won't be eligible for official support from Ross-Tech. Don't waste your time buying a knock off online--they're junk and end up being causing frustration for everyone (you, anyone you ask for help, the official vendor of the software, etc.).

If you're coming from a 17 Explorer, and this is your first TDI, my advice is to not worry too much about performance mods because you're already going to experience a noticeable kick in the butt. Comparing my 2012 non-fix to my 2015 post-fix, I'd say my 2015 drives as well or possibly even better. The downside to the fix is the beating the emissions components endure, which are all covered under warranty. Whatever minor losses of power or economy I experienced, real or imagined, disappeared after phase 2.

Ultimately, though, this is our family wagon and I'm not too worried about it doing anything other than getting from point a to b safely, reliably, and economically. I do play around with my 98 (ALH) bug, though, which can be bought for not much more than a song these days. I agree with IBW above regarding the EA288 (don't have anywhere near his professional experience, to be clear, but notice he did specify best "common rail") while I also consider the ALH the gold standard of diesel engines. Just pointing out if you want to play there are much more cost effective options in terms of bang for buck, imo.

In theory, one could obtain a stock ECM, tune it so it could be used in a different vehicle, and VW would be none the wiser. It wouldn't do much good, though, and cost a *lot* of money to do (cost is always relative, but I'm speculating you'd be looking at spending $2-2.5K for the ECM and tune, if it's even possible and a reputable tuner was willing to do it).

If you're that strongly motived to get a pre-tuned car, some do exist on the market.
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
First, welcome to the TDI world! I think the '15 EA288 engine is the best of VW's common rail diesels. And although the MKVI Jetta was originally built to keep costs down, by 2015 most of the equipment and materials quality you'd expect are back in the car. I think you'll like it.

Regarding swapping ECUs, with older VWs it using another ECU was as easy as getting one with the same part number (essential) and having a tuner delete the immobilizer. I'm not sure it's that easy any longer, as ECU encryption and coding is far more sophisticated than 15 years ago.

Lots of people here are apprehensive about losing warranty coverage by tuning the car. If you're interested in keeping the car largely stock I don't think there's a big downside to running the fixed tune instead of the original. Only significant difference I've noticed is less power on takeoff because of changes to the fueling maps. This is, I believe, more noticeable with the manual cars than automatics.

An aftermarket tune fixes that, but also may jeopardize your warranty.

Thank you sir! A VW diesel tech that I know told me he really likes the 15's. I'm not really worried about the loss of performance post fix. Ignorance is bliss!
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
The best device for diagnostics is a Vag-Com using VCDS: http://www.ross-tech.com/vag-com/ You buy the device and the software (and all future updates) is free. You can buy a used one from someone and you'll still get free software but won't be eligible for official support from Ross-Tech. Don't waste your time buying a knock off online--they're junk and end up being causing frustration for everyone (you, anyone you ask for help, the official vendor of the software, etc.).

If you're coming from a 17 Explorer, and this is your first TDI, my advice is to not worry too much about performance mods because you're already going to experience a noticeable kick in the butt. Comparing my 2012 non-fix to my 2015 post-fix, I'd say my 2015 drives as well or possibly even better. The downside to the fix is the beating the emissions components endure, which are all covered under warranty. Whatever minor losses of power or economy I experienced, real or imagined, disappeared after phase 2.

Ultimately, though, this is our family wagon and I'm not too worried about it doing anything other than getting from point a to b safely, reliably, and economically. I do play around with my 98 (ALH) bug, though, which can be bought for not much more than a song these days. I agree with IBW above regarding the EA288 (don't have anywhere near his professional experience, to be clear, but notice he did specify best "common rail") while I also consider the ALH the gold standard of diesel engines. Just pointing out if you want to play there are much more cost effective options in terms of bang for buck, imo.

In theory, one could obtain a stock ECM, tune it so it could be used in a different vehicle, and VW would be none the wiser. It wouldn't do much good, though, and cost a *lot* of money to do (cost is always relative, but I'm speculating you'd be looking at spending $2-2.5K for the ECM and tune, if it's even possible and a reputable tuner was willing to do it).

If you're that strongly motived to get a pre-tuned car, some do exist on the market.
Thanks for all of the great info! I'm sure the performance will be just fine. Figured I would ask anyways. Quick searched for ECM's popped up with some in the $650 range. Didn't dig any further to confirm they were correct.

I may just have to look for an ALH. Did they make one in a wagon configuration? Thanks again for the help!
 

truman

Top Post Dawg
Joined
May 18, 2000
Location
columbia,MO,usa
TDI
'05 Passat Variant, Still miss the 03JW
As of yesterday, there was a nice example listed here in Neb IIRC. Finding a decent ALH wagon is not an easy task. The general opinion here is that it may be the best car ever made, although a little tight on space.
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
As of yesterday, there was a nice example listed here in Neb IIRC. Finding a decent ALH wagon is not an easy task. The general opinion here is that it may be the best car ever made, although a little tight on space.
I assume they never made one with 4motion, correct?

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IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
They did have 4-motion ones, in Europe. And there's a guy in NY state that imports parts (including the rear floor pan, which is different) to convert one to 4-motion. You need to be committed to AWD to want to go to the effort. Honestly, I've never seen a need for AWD in this car. Good snow tires and driving habits are more than adequate.
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
They did have 4-motion ones, in Europe. And there's a guy in NY state that imports parts (including the rear floor pan, which is different) to convert one to 4-motion. You need to be committed to AWD to want to go to the effort. Honestly, I've never seen a need for AWD in this car. Good snow tires and driving habits are more than adequate.
Cool. I agree. I got around with FWD for years. It doesn't snow that much here in central VA anyways.

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bizzle

Veteran Member
Joined
May 21, 2013
Location
Southern California
TDI
2015 GSW SEL (totaled), 2013 Touareg Executive
Quick searched for ECM's popped up with some in the $650 range. Didn't dig any further to confirm they were correct.
Most of the expense is going to be in the tune to get it to do what you want it to do (if it's possible).

BTW, I was thinking along the lines of obtaining a 2015 wagon for your family car and an inexpensive ALH to bang on and scoot around in. You can find a sweet Golf for a little bit more/less than what you were thinking of doing with the spare ECM :)
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
Most of the expense is going to be in the tune to get it to do what you want it to do (if it's possible).



BTW, I was thinking along the lines of obtaining a 2015 wagon for your family car and an inexpensive ALH to bang on and scoot around in. You can find a sweet Golf for a little bit more/less than what you were thinking of doing with the spare ECM :)
I would be all over a 15 wagon, but the wife doesn't want a "momma wagon". Lol!

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ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
Looks like fuel dilution can be pretty significant on these cars. I plan on testing as this can have a huge impact on the oil change intravals. What kind of oil is everyone running? I run Lubrication Engineers stuff in my tractors and Ford 7.3 diesel, but their 5w-40 can be kind of spendy and it probably can't overcome the fuel dilution issue any better than the other oils out there.

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IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
Looks like fuel dilution can be pretty significant on these cars.
Why do you say this? I've not heard of any, except for concern about it (no actual cases that I've encountered) in states where B20 is often the only fuel available. In those cases VW recommends shortening the oil change interval. Otherwise I don't think it's an issue at all.
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
Why do you say this? I've not heard of any, except for concern about it (no actual cases that I've encountered) in states where B20 is often the only fuel available. In those cases VW recommends shortening the oil change interval. Otherwise I don't think it's an issue at all.
A tribologists friend of mine said something about it. I'm thinking it's related to the post ignition injection event when the fuel is injected on the exhaust stroke. I guess it's part of keeping the particulate filter clean. I need to look into it more. I'll be testing along the way, so I should be able to get some good data. I may even try to replicate the flash point test at my lab.

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andreigbs

Veteran Member
Joined
Sep 27, 2004
Location
Walworth Co., Wisconsin
TDI
N/A
FWIW, and to maintain the extended warranty post-fix, stick to the VW507 spec oils. Plenty of options out there.

As IBW pointed out, I have not read about any fuel dilution concerns except when combined with biodiesel usage.

Drive more, worry less. :)
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
FWIW, and to maintain the extended warranty post-fix, stick to the VW507 spec oils. Plenty of options out there.

As IBW pointed out, I have not read about any fuel dilution concerns except when combined with biodiesel usage.

Drive more, worry less. :)
Thanks a lot for the info! I will make sure to look for that spec. I need to educate myself on the emissions equipment and the differences between the different platforms. Maybe the 14 and earlier cars suffered more from dilution do the lack of def fluid and using other methods to keep the filter clean. I'll have to look into it for sure. This will be the first diesel I've owned that has emissions equipment.

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ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
So the particulate filter is for the soot and the DEF is used to reduce NOX. I assume the car still uses a late injection event in the exhaust stroke to regen the DPF. Is this done in cylinder or outside with a special injector in the exhaust?

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ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
Here it is. Talked them down $1800. They put all new rotors and pads on car too. Tried to get some new tires, but they didn't go for it. It's alright, I have the hookup on tires. Coming from a 16 Explorer Limited. Managed to reduce car payment by $300! So far it is a blast to drive. Can't wait to steal it from the wife when it's dry out. :)

Driver side heated seat not working. They said they would take care of it next week. I just noticed a thread on that and will check it out when I have a chance.


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dhuddleson

Veteran Member
Joined
Jul 15, 2007
Location
Ottawa, Ontario, Canada
TDI
2012 Jetta Highline TDI sedan
Yes, my thread on faulty driver seat heater.



Please let me know if your dealer will tell you what fault there was for the driver seat heating. Without a proper VAGCOM diagnostic performed yet, I don't know what exactly is wrong with mine. All I have at this time is a code "03984" but not enough words to explain what exactly that means.
 

ja_cain

Active member
Joined
Jan 6, 2019
Location
VA
TDI
2015 Jetta SE
Yes, my thread on faulty driver seat heater.



Please let me know if your dealer will tell you what fault there was for the driver seat heating. Without a proper VAGCOM diagnostic performed yet, I don't know what exactly is wrong with mine. All I have at this time is a code "03984" but not enough words to explain what exactly that means.
I will most definitely pass on the info if they share it with me.

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