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Author Topic: Boost not meeting requested, graph inside  (Read 16768 times)

Offline v4rley

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Re: Boost not meeting requested, graph inside
« Reply #30 on: November 02, 2017, 08:01:33 pm »
4 maps original

 Ok I didn’t choose the best measuring block but hey some are ok. Interesting one I think is the boost let me know what it means 😂

Ok so the graphs are grouped, there are 4 runs. Map 1 then 1 then 3 then 5 (as all previous logging)

Sure you guys know but buy clicking on the point on the graph it tells you the value at that point as my first rpm and maf combo doesn’t work well together

Map 1 run 1


Map1 run 2

Map 3



Map5
« Last Edit: November 21, 2017, 11:57:08 am by v4rley »

Offline pudding

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Re: Boost not meeting requested, graph inside
« Reply #31 on: November 03, 2017, 09:54:13 am »
The boost and HPFP graphs are weird!!

If you go to Engine > Advanced ID in VCDS, what numbers do you have showing for Flash attempts and successful flash attempts?   Just wondering if your ECU is corrupted.


2007 ED30 | 2009 TDI 140 | 2016 BMW 330D

Offline v4rley

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Re: Boost not meeting requested, graph inside
« Reply #32 on: November 04, 2017, 02:58:20 pm »
« Last Edit: November 04, 2017, 02:59:52 pm by v4rley »

Offline v4rley

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Re: Boost not meeting requested, graph inside
« Reply #33 on: November 04, 2017, 03:41:45 pm »

Offline v4rley

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Re: Boost not meeting requested, graph inside
« Reply #34 on: November 04, 2017, 09:17:29 pm »
Ok sound wound the actuator on 3 full turns of the hex nut, below are the logs definitely the best peak figure so far but not sure if it runs out of poof sooner

« Last Edit: November 21, 2017, 12:02:43 pm by v4rley »

Offline pudding

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Re: Boost not meeting requested, graph inside
« Reply #35 on: November 06, 2017, 11:40:51 am »
There doesn't appear to be any turbo damage looking at those pics.   What borescope did you use?  The image quality is pretty good.   Did you drop the probe in through the lambda port on the exhaust side, or did you remove the downpipe?   Just wondering if you spun the turbo by hand to see if there was much shaft play?

Maybe the boost is lower because the engine isn't running optimally?  Just thinking cylinder 4 is not happy at all with all that ignition pull.  Perhaps you have a bad injector and it's running lean.   The onset of boost is sluggish as well as not hitting the requests....... I think get the ignition pull sorted and it might return back to normal health.


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Offline Dan_FR

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Re: Boost not meeting requested, graph inside
« Reply #36 on: November 06, 2017, 12:13:20 pm »
That turbo looks pretty good to me. Did you spin it to make sure the bearing doesn't feel rough/uneven or have an abnormal amount of resistance and/or play?

As for the timing pull, have you actually logged how much timing you are running at the same time so we can see how much timing you're actually getting? Can't say I've seen it in any of the logs? I don't think the timing pull is the cause of the turbo or performance issue at all. The throttle isn't closing so the car isn't THAT unhappy. I've personally seen that level of timing pull during some logging/testing/tweaking of Revo software on my own car and it most definitely did not pull back boost levels as a result

Would have expected the actuator tweak to help a lot more if it was the cause of the problem.

Silly question, but have you checked to see if you have the correct MAP sensor fitted to the car? Your MAF values are good, and you say there's no leak, so I'm wondering if the wrong sensor is fitted.... a 3 Bar sensor fitted to a 2.5 bar calibration will make the ECU see lower boost than you actually have..

E.G. You could see several hundred mbar difference between the two sensors. Don't suppose you have an aftermarket gauge plumbed in to the inlet manifold?
TFSI... Revo Stage 2+... . WMI.... VCDS HEX + CAN, MPPS, VAG Commander & VAG tacho - South Wales

Offline pudding

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Re: Boost not meeting requested, graph inside
« Reply #37 on: November 06, 2017, 12:24:49 pm »
If the cylinder is delaying the burn and thusly the cylinder pressure / contribution drops, flow through the engine is reduced and that includes exhaust flow over the turbine wheel, no?

That amount of pull is not good.  I get -2 KW at the most running a lot more boost than that.  I'd be looking to get that as close to zero as possible before going any further.....personally.


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Offline Dan_FR

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Re: Boost not meeting requested, graph inside
« Reply #38 on: November 06, 2017, 12:46:34 pm »
Negligible effect on boost levels and wouldn't cause a 4 PSI deficit across the RPM range - based on my own experience with a K03. Besides, looking at the log, the knock level is not constant and it is peaking, most likely at a certain load/RPM so wouldn't explain the drop across the entire rev range

The amount of correction is based on the severity of the knock detected and will depend entirely on the requested ignition timing - its not comparable on different cars & setups. Its not ideal but the ECU can deal with up to 12CF so its not an issue for the purposes of this diagnosis. At 2CF you probably have no real knocking going on and you may not even have any reduction in timing, its just a Correction Factor and does not directly translate to X amount of degrees of timing retardation

Anything up to 5CF for short periods is fine anyway based on what I have seen over the years from many logs and heard from tuners themselves, 2CF at most tells me you have a safe map with headroom for more, but again it depends on a lot - ambient conditions, whether your 2CF peak was after a single run or after repeated back to back runs for maximum heat etc.

Off topic a little, sorry!  :signLOL:
« Last Edit: November 06, 2017, 12:55:08 pm by Dan_FR »
TFSI... Revo Stage 2+... . WMI.... VCDS HEX + CAN, MPPS, VAG Commander & VAG tacho - South Wales

Offline v4rley

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Re: Boost not meeting requested, graph inside
« Reply #39 on: November 06, 2017, 12:50:37 pm »
Yeah the turbo looked good to me, part of me was hoping to see issue to resolve the problem but alas not. Just the standard cheap borescope from eBay pretty good although the mirror angle bit is crap.

I cheated and use the lambda for the exhaust side, did consider removing the downpipe for inspecting the play maybe something to consider. With regards to the play i have a k03 in the garage, when I put the airline into the cold side it spun the wheels but when I replicate this on the car it didn’t, although not sure if that is just due to the resistance from the one on the car having oil / coolant amounts it.

All my logs are on this thread so haven’t got the timing ones. Can you point me in the direction of which measuring blocks and I’ll log them tonight.

I had a rare misfire issue months ago, mainly at low speed and usually over speed bump, this was cylinder 4 and maybe also 2. The injectors were replaced with a freshly cleaned set prior to mapping
« Last Edit: November 06, 2017, 12:52:49 pm by v4rley »

Offline Dan_FR

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Re: Boost not meeting requested, graph inside
« Reply #40 on: November 06, 2017, 12:53:45 pm »
003-4 is ignition timing, I refer to this all the time for logging addresses http://www.goapr.co.uk/support/datalogging.php

I don't think it is relevant at all to the problem you are having

Not comparable on the car as the turbo may no be able to spin as the TB will be shut so the air has nowhere to go unfortunately.
TFSI... Revo Stage 2+... . WMI.... VCDS HEX + CAN, MPPS, VAG Commander & VAG tacho - South Wales

Offline v4rley

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Re: Boost not meeting requested, graph inside
« Reply #41 on: November 06, 2017, 12:59:04 pm »
Ok so I need to check the map sensor, what would be the next avenue to try? Would you try more preload?

Offline v4rley

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Re: Boost not meeting requested, graph inside
« Reply #42 on: November 06, 2017, 01:27:59 pm »
Do you know why on these logs showing differently map setting, alway request the maximum but the actual boost seems to be map specific?

Offline Dan_FR

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Re: Boost not meeting requested, graph inside
« Reply #43 on: November 06, 2017, 01:53:14 pm »
Its the way Niki sets up the switchable mapping, its done via the N75DC request rather than what will show on VCDS under 'specified'....

But the specified shown is achievable on a K03 on 100%DC. Mine peaks at around 1.3-1.4 bar and tails off to 0.8-0.9 bar at the redline
TFSI... Revo Stage 2+... . WMI.... VCDS HEX + CAN, MPPS, VAG Commander & VAG tacho - South Wales

Offline v4rley

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Re: Boost not meeting requested, graph inside
« Reply #44 on: November 06, 2017, 04:14:19 pm »
Ah ok thanks makes sense,

So on the latest set of boost logs (after preload tweak)  my peak is the same / higher than yours but is a good 3-4psi lower at the redline.