Technical Why my car no work? :(

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Technical Why my car no work? :(

just try parked up ,idling and log revs, desired boost , actual boost and vnt%
let idle ,rev slowly to increase revs upto 3000 and back to idle again.
in similar test I only saw overboost by a few hundred mbar say requested 1200-1300mbar and actual 1300-1400
if anything it looks like its overboosting from desired and also the boost seems to follow the revs, as if the vnt solenoid is not venting stuck full spool or turbo vanes stuck full spool.
also verify the turbo actuator moves in/out on engine start stop.
its hard to say the most useful data I have is mostly under load out on the road, but looks like youd struggle.
 
boost and revs vnt for dave.png
heres one of mine when I had a map sensor over reading by around 70mbar or so.
it will give a good idea of weather the vnt part of the system is relieving boost or not.
as no load parked up it should not be getting or requesting much boost
 
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thought about this overnight and I may be giving you a bad example in that graph above , as I have a hybrid turbo and remap and I don't know whether that data was before or after those mods.
in my map the open loop and closed loop parameters are altered for where the vnt % switches open to closed loop, so your vnt % may not get anywhere near as low as mine in that example and hence the boost may be higher.
I still don't think it should be much higher than desired boost so still a worthy log to do.
 
had another look through old logs and think ive found one with hybrid turbo but before remap.
again just parked up idling then reving slowly up then back down to idle
boost and revs vnt for dave 2 before map.png
I also have fuel qty on this one, if your fuel qty is significantly higher in order to get engine to rev up may also signify that egr gas is leaking in and killing combustion maybe.
edit
actually the vnt is not at 75% at idle so this was in process of writing some map data.
 
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my actuator thing seems to be moving, ive done a vid not sure if its clear though will upload it if it is.
i then went to conect laptop and do the other things you said but now i have flat battery :bang:

also noticed ive a coolant leak that looks like it could be water pump ( that's not that old ):(

and its now pouring with rain :cry:
 
i put battery back on, started and it seemed to be fine, i took it for a drive it drove ok at first i pulled into garden centre and saved graph. then drove back home and it was broke again :( ( i couldn't remember what vnt means :eek:)


1st run that seemed ok
firt run.JPG

2nd run home seemed dead again
2nd run.JPG


on the drive when i got back.
drive.JPG


:confused:
 
you still have overboost by a few hundred mbar
try to recreate a graph similar to mine
just revs ,act boost, desired boost , and vnt% slowlt rev to 2000 and back
also id be interested to see a graph similar to one I posted of
https://www.fiatforum.com/attachment.php?attachmentid=127805&d=1386875882
desired maf, actual maf , egr solenoid% you will need to log a few minutes to see egr go through a cycle or 2 just let it idle
vnt is just 'variable nozzle turbo' or similar meaning internal vanes help to spool more boost or relieve excess boost regardless of engine revs to some degree.
when you say was ok driving there but broke on way back what do you mean by broke?
low power , stuttering, or eml light?
looking more closely at this graph you have one spot with underboost ive circled red
overboost but spot of underboost for dave.jpg
for how long it would take id still try blanking egr.
 
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its boost control solenoid % (down by boost bits above egr valve opening%)
theres no real time feed back of what the vnt actuator or vanes are doing, only the desired position of the boost control solenoid %, so if for example the solenoid is seized or sticky or the pipe after or before the solenoid is holed or leaky , the actual position of the actuator and vanes is not where the ecu thinks it is.
if it lost power (with no eml lights and limp mode) id still say egr leaking in (boost leaking out)or maf reading very low
did the loss of power occur at the point of the red circle I added to your graph bottom page 2 ,about 2/3rd of the way home looks like you came from a fast spell to a cruise to stop and then went to accelerate and it slowly increased revs, then ok for the last bit home although you didn't give it any beans after that.
do the maf desired maf and egr opening% first for say 6 min hopefully when it opens with a bit of luck we may see it not fully seal shut via odd maf readings
you want to see
https://www.fiatforum.com/attachment.php?attachmentid=127805&d=1386875882
after that id be fitting an egr blank(and live with the eml light for now, you get no limp mode just the light)
 
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it only has to not seal completely air tight and next time you go to accelerate all that lovely boost will disappear through it into the exhaust.
to prove it on a log (if you can catch it exactly when leaking) is to just log actual maf airflow and actual boost and egr valve opening ,nothing else go for a drive plenty of accelerations and log and when you get back take the data from log and divide boost by maf.(boost/maf) and you should get a constant figure around 2 when egr is not open, obviously where egr does open the figure will be way off 2 but also if it goes way off 2 and egr was supposed to be shut you can sumise its leaking
 
here is an old log when I still had egr fitted.
boost div maf for dave.png
I have highlighted where egr would have been open on coasting / low load and you see the maf drop(as engine is now breathing egr gas so maf drops)
and you can see that the boost divided by maf value goes way off the normal(just under 2 )value up to over 2.5.
so if you log egr valve opening also to prove if its supposed to be open or not.
so just maf, boost and egr opening%.
in excel
boost div maf for dave log.png
 
thanks for all that, i think ive done these right.

1st one is on my drive i then went for a little drive 2nd graph.
3rd graph on way back from a short run car seem to fix its self.:confused:

so i grabbed phone and a coffee and drove to asda 4th and 5th graph, car still seemed fixed.

6th graph is in asda carpark so i could compare it to 1st one.

on the way back to asda car still seems fixed.

n1.JPG

n2.JPG

n3 but ok.JPG

n4 ok.JPG

n5 ok.JPG

n6 asda.JPG

only thing ive done today is reclean map, because first time i did it i'd ran out of spray electric contact cleaner and i used brake cleaner, today i found some old cassette tape head cleaning fluid so used that, i wonder if that worked better than the brake cleaner but took time to dry? :confused: boost presure was all over the place on first static test but on the last graph 2nd static test its smooth.
 
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If you do more graphs , use the maf airflow mg/i and not maf signal ms.
Also dont bother with the others like atmos pressure, boost mv etc.
The more signals you log the slower the sample rate.
Thats may be part reason the last looks so good , as well as the log timescale.
Hope youve sorted it,
Still like to see a maf airflow and actual boost and egr on say a 4th gear pull.
And on another
a maf airflow and actual boost and desired boost and vnt , same again 4th gear pull.
 
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