So following on from a topic I started and a topic I have been contributing to regarding my turbo sounding a bit like a dentist drill, I have done a bit of (amateur) data logging. I have done this on my own so it is through multiple gears and looks a bit messy, but hopefully it is still some use.

 

Please would you chaps who are in the know provide me some feedback on these results? Although I have a high level understanding of what I am seeing here I don't particularly understand the data and its characteristics.

 

Any logging I've done for mapping purposes for Faboka has been a single wide open throttle run from 1500rpm to the Rev limiter usually in 4th gear.

That would have been easy if I had someone to be clicking go on the laptop lol

I wanted to establish whether or not my turbo was setup correctly on the stop screw not tweak a map. Is this type of data displayed like this no good?

The specified and actual boost looks "ok" to me but I haven't a clue about the duty cycle and what that should look like.

sent from my Samsung Note 4.

The more I've read the more I'm thinking that graph is useless lol ill do another one tomorrow on a quieter road.

sent from my Samsung Note 4.

You don't check the stop screw by logging,stop screw is checked by going into basic settings,then number 11 with car at normal temp idling.

Vcds will raise the revs and it will display a 'on' figure,and a 'off' figure.iirc you want to see 125mbar difference between the numbers.

To check your actuator rod length you log group11,wide open throttle from 1500rpm to rev limiter,then check the % on the log at 4000rpm,should be between 70 and 80%.

Please do another one.

 

Just set it up in a layby and leave to run.  This is how I do my data logging when I get sent new maps and need to give feedback to the mapper.   Stick in 4th - 30mph or so and floor it to the redline.  Do it in 3rd gear if you are concerned about the speed approaching the redline.   I know I run in 3rd as I am still doing naughty speeds at the redline, even in 3rd gear (doesn't help my limiter is up at 5200rpm now though)

 

From what I can tell on there, actual and specified boost appear to be following each other OK.  If its making a noise like a drill, it sounds like its on the way out and isn't something VCDS will find for you (until it blows up at least)

I was hoping that by doing this it would at least give some indication as to whether or not the turbo actuator had been setup correctly. There was a suspicion that it hadn't with it being a recon turbo that I didn't have a clue where it came from (via warranty company).

This does a bit embarrassingly highlight a lack of understanding on my behalf as I thought the stop screw was what adjusted the length of the actuator arm.

I was hoping by doing this it would show whether the VNT mechanism was opening and closing correctly based on the actuator rod length being set right.

Am I a million miles off the mark here? Lol

sent from my Samsung Note 4.

You don't check the stop screw by logging,stop screw is checked by going into basic settings,then number 11 with car at normal temp idling.

Vcds will raise the revs and it will display a 'on' figure,and a 'off' figure.iirc you want to see 125mbar difference between the numbers.

To check your actuator rod length you log group11,wide open throttle from 1500rpm to rev limiter,then check the % on the log at 4000rpm,should be between 70 and 80%.

I've taught you well old padawan

Ash, send me your csv file.

Ash, send me your csv file.

Here it is, downloadable from Box, wasn't sure the best way to send this. Thanks for taking the time to look, very much appreciated.

 

https://app.box.com/s/q7lgdi5lxtiqk2tp0wt2xy2npw752i88

 

I was 100% expecting to get flamed here as it is totally new territory for me! lol (in case you hadn't noticed...)

 

Thanks all for being gentle :clap:    :sun:  :peek:

A full in gear run will also give a better duty cycle readout too.  Ideally you want to be around 70% duty cycle at 4000 revs on a full throttle run.  I think it's 70% anyway - or a little higher.

A full in gear run will also give a better duty cycle readout too.  Ideally you want to be around 70% duty cycle at 4000 revs on a full throttle run.  I think it's 70% anyway - or a little higher.

I'll have another go at logging tomorrow, this first attempt was never going to be as fruitful as I hoped. the pedal was to the metal until after 4000 rpm in 2nd 3rd and 4th gear on that run (just I think my bloody car mat had slipped which was keeping the pedal raised slightly more but this was consistent throughout that log).

 

I think you may be right Devonutopia, the turbo may be feeling sorry for itself, its just it has been doing this for 30,000 miles now and appeared when I had the shark map flashed. There was a faint whistle before the map after the warranty company turbo was fitted but other than the noise the car has always "seemed" to run fine.

To be honest mate, not many people know how to do this. Most think VCDS is just for reading fault codes.

 

I always (personal preference) graph it against RPM, not time. I've attached a graph that is for the full log. The second is what looks like a couple of full WOT runs. I've attached the duty cycle on this one.

 

Some people have different opinions of the duty cycle. Mine is it should be between high 60% to low 70% on a stock map.

 

Looks pretty alright to me but like others have said a 4th gear log from 1500 rpm to redline is best. You don't have to click start when you are about to carry WOT out. I click start on my drive then drive to the location, carry out the runs then drive home. Then I click stop.

Thanks very much faboka for providing input and having a look at this, I really do appreciate it.

I do have a keen interest in stuff like this but I have no real underpinning knowledge like coskev, devonutopia, yourself etc. Before this first play with VCDS I just used torque on my phone for fault code reading! Lol

I think I'll have a butchers at the turbo tomorrow morning and see if there is bit more of an obvious fault.

Thanks again everyone!

sent from my Samsung Note 4.