VCDS log is there something amiss?

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
Your injector balance is good.

Your air flow at idle is higher than it should be, but it is hard to tell if that is MAF offset error or due to a leak.

Can you take a log of group 10 and another group that shows RPM, such as 3 at the same time? Do this on a full pedal run from 1800 to 4000 rpm in 4th gear. Start from loafing, no pedal, at 1800 rpm, then floor it and hold it to the floor until you reach 4000 rpm. Then show us that data.

Or better yet, email it to me.

As I have said before, I think you have a boost leak.
What have you done to search for a boost leak?
 

panteramatt

Veteran Member
Joined
Mar 27, 2015
Location
South Jersey
TDI
2003 golf
I havent been able to do much due to work and on the weekends I gotta catch up. Itll be a while til I get another log. Anyway while I was doing this log it went into "limp" mode I guess cause I couldnt build more than 5 lbs of boost til I turned the car off. This is the third time since I bought the car it has done this. Theres no CEL so what could be causing this?
 

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
Bad seal of nipple on vacuum pump? Brake vacuum boost line?
 

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
What's up with this?

,4.37,500.0,1009.8,1009.8,0.0,,,,,,,,,,
,4.68,500.0,1009.8,1009.8,0.0,,,,,,,,,,
,7.18,480.0,1009.8,999.6,0.0,,,,,,,,,,
,7.49,485.0,1009.8,1009.8,0.0,,,,,,,,,,
,7.80,495.0,1009.8,1009.8,0.0,,,,,,,,,,


Why the dip there at 7.18? Just wondering if the MAP could somehow be flaky. Maybe there's a leak there? (though not in this data grab here, but when big boost is happening)
 

robnitro

Veteran Member
Joined
Jan 19, 2004
Location
NYC area, NY
TDI
2001 Jetta TDI GLS silver
This data doesn't help much. The little dip is fine, it's because the value is between 1009 and 999 but vcds only sees in intervals of 10.2 it seems, so it may dip there. No problem.

Do a log from 2200 or so, wot. I don't like using 1800 rpm, some people can have excessive surge and if on the limit of the turbo you can have problems, especially with control issues suspect.

Under boost pressure we can see if there is a big or small leak.
 
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panteramatt

Veteran Member
Joined
Mar 27, 2015
Location
South Jersey
TDI
2003 golf
Alright fellas terribly sorry for taking forever to respond. Anyway was under the car today with it running and noticed oil leaking from the exhaust manifold and there is a little air leak there where it mates to the head. I could hear what I though was an air leak too but the engine rattles to much who know what I heard. Anyway, would the manifold leak really cause a noticeable difference? Its not bad but it is leaking oil from the left corner of the manifold. Tried tightening up the studs but their really tight.
 

panteramatt

Veteran Member
Joined
Mar 27, 2015
Location
South Jersey
TDI
2003 golf
Basically Im not sure if theres a problem or not here. I bought the car modded and never driven another tdi so maybe my expectations are too high but it hit pretty hard at 2000 rpms but when I get on the highway in 4th it just doesnt accelerate hard like I believe it should. I mean I have a jacked up powerstroke and it accelerates hard all the way to redline and I think this car should too given how light it is with all these mods.
 

robnitro

Veteran Member
Joined
Jan 19, 2004
Location
NYC area, NY
TDI
2001 Jetta TDI GLS silver
Do a wot log in 3rd or 4th- group 1 and group 10
and if you can, do another, just group 11

Then, I can say what might be wrong, like the leak would show up etc.

Btw, don't expect full power at 2k, I have mine tuned at 2250 and up. It's a short stroke high speed diesel!
 
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