a couple of logs with graphs. Boost and MAF

claytski

Veteran Member
Joined
Jul 19, 2007
Location
jefferson, nh
TDI
98 jetta tdi
I have been running not so right lately and from what I can tell, this explains it. any direction on my problem would be great. here are that graphs:





btw, that was foot glued to the floor from start to finish. it was a 4th gear pull from the rpm specified on the bottom of the graph.
 

claytski

Veteran Member
Joined
Jul 19, 2007
Location
jefferson, nh
TDI
98 jetta tdi
more logs.

here are 2 more logs. I got a CEL for intake manifold pressure something arother. I replaced all the boost lines and vacuum lines in the whole car including ECU one. that fixed the CEL. here are the results after the lines were replaced. the logs were taken on 2 different road sections.











 

claytski

Veteran Member
Joined
Jul 19, 2007
Location
jefferson, nh
TDI
98 jetta tdi
as you can see, the lines being replaced fixed my boost up and down.

my MAF is all over the chart after 2700 roughly.

just a thought, would a clogged cat do something like this? it seems like an air restriction.
 
Last edited:

claytski

Veteran Member
Joined
Jul 19, 2007
Location
jefferson, nh
TDI
98 jetta tdi
today I did another run for the maf. this was after I cut the snow screen out of the airbox, I am also running no cat back as it rotted off from salt on the roads.
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
was the only difference between this run and the prior ones the snowscreen - or the cat and snowscreen? This looks pretty much normal for a wastegated tdi (at least, about what my B4 does).
 

claytski

Veteran Member
Joined
Jul 19, 2007
Location
jefferson, nh
TDI
98 jetta tdi
unfortunatly its both the snowscreen and the cat back missing. I have some fuel curves to post too. the IQ goes down as rpm goes up. one would think the IQ would go up as the rpm goes up.
 

mittzlepick

Veteran Member
Joined
Mar 18, 2001
Location
union maine
TDI
2004 jetta wagon (365k)2001 wagon tire burner 6spd 2003 wagon(417k)
if you pulled the snowscreen out you may want to put a rodent screen in I used 1/2 rabbit cage wire as those little ****ers ate my 40 dollar amsoil filter and filled my box with nuts. I wish I could see them stuck to the filter when I went down the road.
 
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