How do I know if my car already has a tune?

MATPOC

Veteran Member
Joined
Dec 28, 2020
Location
Providence, near Hope
TDI
2003 Jetta Wagon 5-speed
Maybe a dumb question, please delete if it's been covered, but I'm wondering if my '03 JSW already has a tune?
I'm 3d owner, friend just gave it to me because it needed bunch of things, didn't tell me much, just handed me 17 years worth of service records...
Going through the car I found KII USB dongle, he didn't know what it was, just left it in there for me to find. I already installed software and it works fine.
He has no idea what was done to the car other than dealer service receipts... Makes me wonder if this thing has a tune? First owner was a VW fanatic...

When I first got it seemed very slow, but after I replaced filters and cleaned the EGR it got little better, but then on the next trip it went in to a limp mode, then it was fine next day. I've taken few long drives (30-45 minutes) and it seems to have gradually improved performance, no more limp mode, pretty good acceleration above 3,000 rpm, seat of the pants it feels more than 90hp, not quite as fast as my other car but definitely not slow. If it has a tune I wouldn't know it because I have no idea what stock ALH feels like, never had a diesel in my life (life long Honda Fanboy) and only a couple Turbo cars, both Volvo.
 

NewTdi

Top Post Dawg
Joined
Jan 15, 2004
Location
NorCal
TDI
2003 Bora, Reflex Silver
Those clogged intakes and EGR can really kill performance. Mind someone nearby who has a stock ALH car and they will be able to tell you in a heartbeat if it is stock or not. Regardless enjoy the car.
 

MATPOC

Veteran Member
Joined
Dec 28, 2020
Location
Providence, near Hope
TDI
2003 Jetta Wagon 5-speed
Those clogged intakes and EGR can really kill performance. Mind someone nearby who has a stock ALH car and they will be able to tell you in a heartbeat if it is stock or not. Regardless enjoy the car.
I have the VCDS tool, can it be used to figure that out?

 

Mozambiquer

Vendor , w/Business number
Joined
Mar 21, 2015
Location
Versailles Missouri
TDI
1998 VW Jetta TDI. 1982 VW Rabbit pickup, 2001 VW Jetta TDI
There's a spot with vcds that you can check and see if it's been programmed, I ran across it the other day, but don't remember where it was... Many times, if the egr is still intact it's probably still stock, but there are people who do a tune without an egr delete, especially in areas that will check that.
 

MATPOC

Veteran Member
Joined
Dec 28, 2020
Location
Providence, near Hope
TDI
2003 Jetta Wagon 5-speed
what is standard boost on 2003 ALH? Mine seems to be about 2000mb, (14.7psi?)

dove around with laptop and it went in to limp mode again when I had it flat out in 4th gear, can see the green line is desired, yellow actual boost (about 2200mb) so I'm gonna pull intake and clean it, also replace vacuum hoses, then test it again, I have a link to limp mode step by step diagnostic, will follow that, hope it's not a turbo


 

yahmon

Veteran Member
Joined
Dec 27, 2012
Location
canada
TDI
04 passat tdi 6spd stage2 webasto TC3 , 04 passatW8 6 spd, 10 Jetta TDI 6spd stage 1
requested boost is 1950 if I am not mistaken, you might want to check actuator movement for sticking
 

Rrusse11

Veteran Member
Joined
Jan 23, 2014
Location
PA Deutsch Country
TDI
2002 Golf, 5spd; 05 Jeep CRD
Check the actuator with a mityvac and have a good look at all the vacuum lines. A can of diesel purge in the fuel filter housing is a good idea, the injectors could be gummed up to.
 

MATPOC

Veteran Member
Joined
Dec 28, 2020
Location
Providence, near Hope
TDI
2003 Jetta Wagon 5-speed
Check the actuator with a mityvac and have a good look at all the vacuum lines. A can of diesel purge in the fuel filter housing is a good idea, the injectors could be gummed up to.

Did Diesel purge when I changed filters 200 miles ago.
Picked up intake cleaning kit and vacuum tubing from ID parts so that is my next project...
Checked Injector balance with VCDS and it seems good, so I was told...
 

MukGyver

Veteran Member
Joined
Dec 11, 2020
Location
Sierra Ca
TDI
2004 Jetta PD
Check for smooth movement of the boost control vane lever. (where the turbo actuator hooks up) might have sticking vanes.

edit: could be vacuum leak too. the erratic yellow line makes me think vanes.
 
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