I am kinda new to the Tdi world and am trying to learn things especially around the vcds software now getting more and more involved.
I haven't been experiencing good fuel economy at all. I am currently getting roughly 700 KM to a tank and in my eyes that is horrible. Since i got the car 1 year ago it has declined roughly 100kms per tank and i believe it goes down more every tank. i am currently focusing my searches around the vacuum area for the time being and will move on from there.
i just changed fuel and air filter today to have a look at how much of a difference the air filter will make as it was quite dirty. however recently i went to get this car tuned as it does have larger nozzles as well as a larger 11mm lift pump as i was told by the previous owner it however does not have a tune so i know i am losing some of the fuel economy to that but i am sure it isn't 300-500km worth. they told me to do a series of tests to tell them if the car is ready for tunes or not and they said the turbo actuator is not moving as much as they'd like or at least it isn't moving fully at startup or shut down i cant remember which it was i believe startup.
i have adjusted timing and IQ and all is good there running an IQ of about 4.5 and timing is very very slightly advanced enough to bounce off the perfect mark in VCDS. i am going to post some logs of pulls, and first just kinda regular driving conditions the second being a pull and the third being a everything but mainly a cruise. i looked mainly at my pull log at the boost and the MAF readings; the boost is reading slightly higher than the requested and doesn't ever drop below the requested like i am seeing most people are saying should be happening? So what i am asking is how are these readings looking to you guys are they any good is my MAF bad as it isnt ever going all the way up to 1100 or even close and also reads roughly 470 at idle.
drive.google.com
If it is MAF sensor then it would explain why i am not getting good fuel economy. I was going to do another series of logs tomorrow as well as testing to see if unplugging the MAF as suggest by a few gets any better. As far as a loss in power i don't know as it is my first jetta.
Should this be a vacuum related issue where should i start with testing into things? i pulled the line off the vacuum accumulator and put my finger on it and it has relatively strong suction not sure what it us supposed to be but it feels quite good to me but that is at the accumulator could my N75 not be good anymore?
What would be the best course of action to get started here? i have ran several bottles of injector clesner through nealry with every fill up as i do with all my diesels. as well as 2 bottles of diesel purge one stright diesel purge in fuel filter when i did the change, however as i stated i did do this change today and anything i do does take a couple of weeks to go through a tank to be able to see if it is changed or not unless i go out driving aimlessly.
car is a 2001 jetta tdi ALH engine
Have been trying different driving styles, tried driving very eco friendly i.e never going above 1500-2k rpm tried heavy and tried a mix. I have also tried very eco with a small pull every now and again as suggest by a couple of threads still no change, i should also state that it is very consistent around 700km regardless of driving style unless im really on it.
EGR is stock and i pulled it to check yesterday and is very very clean, it has an oil buildup but other than that no build-up, cant say the same for my duramax lol....
I haven't been experiencing good fuel economy at all. I am currently getting roughly 700 KM to a tank and in my eyes that is horrible. Since i got the car 1 year ago it has declined roughly 100kms per tank and i believe it goes down more every tank. i am currently focusing my searches around the vacuum area for the time being and will move on from there.
i just changed fuel and air filter today to have a look at how much of a difference the air filter will make as it was quite dirty. however recently i went to get this car tuned as it does have larger nozzles as well as a larger 11mm lift pump as i was told by the previous owner it however does not have a tune so i know i am losing some of the fuel economy to that but i am sure it isn't 300-500km worth. they told me to do a series of tests to tell them if the car is ready for tunes or not and they said the turbo actuator is not moving as much as they'd like or at least it isn't moving fully at startup or shut down i cant remember which it was i believe startup.
i have adjusted timing and IQ and all is good there running an IQ of about 4.5 and timing is very very slightly advanced enough to bounce off the perfect mark in VCDS. i am going to post some logs of pulls, and first just kinda regular driving conditions the second being a pull and the third being a everything but mainly a cruise. i looked mainly at my pull log at the boost and the MAF readings; the boost is reading slightly higher than the requested and doesn't ever drop below the requested like i am seeing most people are saying should be happening? So what i am asking is how are these readings looking to you guys are they any good is my MAF bad as it isnt ever going all the way up to 1100 or even close and also reads roughly 470 at idle.
Untitled folder - Google Drive
drive.google.com
If it is MAF sensor then it would explain why i am not getting good fuel economy. I was going to do another series of logs tomorrow as well as testing to see if unplugging the MAF as suggest by a few gets any better. As far as a loss in power i don't know as it is my first jetta.
Should this be a vacuum related issue where should i start with testing into things? i pulled the line off the vacuum accumulator and put my finger on it and it has relatively strong suction not sure what it us supposed to be but it feels quite good to me but that is at the accumulator could my N75 not be good anymore?
What would be the best course of action to get started here? i have ran several bottles of injector clesner through nealry with every fill up as i do with all my diesels. as well as 2 bottles of diesel purge one stright diesel purge in fuel filter when i did the change, however as i stated i did do this change today and anything i do does take a couple of weeks to go through a tank to be able to see if it is changed or not unless i go out driving aimlessly.
car is a 2001 jetta tdi ALH engine
Have been trying different driving styles, tried driving very eco friendly i.e never going above 1500-2k rpm tried heavy and tried a mix. I have also tried very eco with a small pull every now and again as suggest by a couple of threads still no change, i should also state that it is very consistent around 700km regardless of driving style unless im really on it.
EGR is stock and i pulled it to check yesterday and is very very clean, it has an oil buildup but other than that no build-up, cant say the same for my duramax lol....
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