how to adjust iq with vag com.


Top Post Dawg
Apr 14, 2005
West Hill, Ont. Nov.2nd in Mexico till April 27th
2015 Passat Highline TDI Candy White (SEL Premium) long gone 2002 Jetta TDI
This is what I have in my records, it was not written by me:

IQ adjustment

1) Open the Vag-com software.
2) Click on ENGINE.
3) Click on LOG IN
4) Enter 12233 in the login field then click DO IT.
5) Click on ADAPTATION.
6) It should already be in channel 1, which is what you need for IQ adjustments.
7) Note the reported IQ number (usually between 2-4mg/r)
8) Adjust the value from 32768 to something like 32750 and see what the IQ changes to.
9) keep adjusting the value till you get about 1mg/r more than what you started with.
So if your stock setting is 3mg/r, increase it to 4mg/r.
10) save the new value & take for a test drive.

Note: All cars are different. They all come from the factory with different mg/r readings
even if the adaptation value is the same (32768). Go up by 1mg/r, save, then test drive.
Repeat as necessary increasing the IQ reading by 1mg/r till you are comfortable with the
smoke level & the shudder is gone. For most cars, this is around 5mg/r, but as I said,
all cars are different and a little trial & error will be required to fine tune it.
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TDIClub Enthusiast, Principal IDParts, Vendor , w/
Aug 16, 2004
South of Boston
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
Higher number will equal less smoke and lower torque. It won't affect HP to any degree.


Veteran Member
Jan 20, 2006
Etobicoke, ON, Canada
2001 Golf TDI 1.9L
I have my IQ up at about 5.9 right now. Is there any danger in having it too high (fueling too low)? My torque is down too low now, so I think I need to go back to somewhere near 5.0.