General Boost Solenoid Failure????

[sussexa]

here is the boost map (I think for your 115hp)

so just over 1 bar boost to be expected 1.1bar wouldn't be supprised to see spikes to 1.2 to 1.3 bar on spool up then settle down a bit back to 1.1 -1bar
you can see on the right column the boost rises up to 2500 revs then drops again towards 5000 revs.
and this is only if its getting maximum fuel of 64mm3
so if your not full throttle it wont ask full boost example half throttle at 3000 revs may well be 0.8bar boost.
2 bar is for sure too high for any std turbo and will be wearing the thrust bearings quickly and probably overspooling turbo.
we all need to be clear what units were reading as 2000mbar boost pressure in fes/mes is not 2bar boost it is approx. 1 bar boost as its absolute so at no boost and at sea level will read approx. 1000mbar.
boost gauges are mostly if not all bar gauge or psi so at sea level should read 0bar
Mario does your gauge state it will read vacuum at all?
if it will read vacuum to below -0.6bar you could try to read the vacuum pressure at the vnt actuator pipe at the turbo, with the car idling vnt should be at maximum and at around -0.6bar at that pipe.
just checked back you did visuals on vnt actuator movement sounds good , have you had a real good look around for a boost leak ? black smoke and low boost pressure ?
theres turbo to intercooler pipe , intercooler , intercooler to manifold to check closely.
its been a while since anyones mentioned a boost leak I think but I think they mostly used to be the turbo to intercooler pipe, as it rubs on a stud or something in the wheel arch rings a bell.

found one with pics, you can just see the hose running through the archliner area to the intercooler
https://www.fiatforum.com/stilo/228809-1-9jtd-intercooler-turbo-split-pipe.html

 

[MazCinq]

Cheers mate, ok I do have some answers,

Vac, yes my gauge does read vac as I did connect it to start with between the inlet and the solenoid, the reading there was 0.8 not sure if that helps.

On full throttle I can get it to hit 1.1bar but it's only for a split second in third only at around 3k, it then drops to 0.9

Black smoke, check, since fitting the new MAF there is lots of that, and I mean lots, I will hook my dash cam up out the back window and go for a drive to show you.

I have always had turbo whistle when on boost, is this normal??? I have tried to get this on video but it's hard to pick up, I am leaning towards a boost leak as the car has been in a bump at some point as all the front plastics are busy and the airbox was a mess hence why I fitted a cone filter.

 

[roy lovelock]

have you checked your intercooler pipe work for any tears or rips, they usually wear though where it passes though the plastic under trays (it goes from your intercooler to your turbo).
you say turbo whistle is it more like a whoosh, if it is then i would have a very close look at that pipework.
The symptoms are inline with a leak and i think you have the tell tale signs of this problem.

 

[MazCinq]

Cheers, well i have got my egr blank and elm327 wifi thingy so I am going out there today to mess around with it so I will check the boost piping closely. Kind of half hope it is leaking as then it gives me an excuse to fit shorter alloy piping and maybe a front mount.

 

[MazCinq]

ok, so got my WiFi ELM327 arrived today, connected to the ECU instantly and got the readings I think I need.








"Time" "Engine speed" "Boost pressure" "Desired boost pressure" "Boost control/solenoid" "TAG"
"sec" "rpm" "mBar" "mBar" "%" " "
0.00 845.0000 1009.0000 1025.0000 75.0000 ""
1.74 849.0000 1007.0000 1025.0000 75.0000 ""
2.75 851.0000 1007.0000 1023.0000 75.0000 ""
3.77 847.0000 1007.0000 1026.0000 75.0000 ""
4.58 852.0000 1007.0000 1026.0000 75.0000 ""
5.83 853.0000 1007.0000 1024.0000 75.0000 ""
7.57 849.0000 1007.0000 1022.0000 75.0000 ""
8.84 850.0000 1007.0000 1025.0000 75.0000 ""
10.09 848.0000 1007.0000 1027.0000 75.0000 ""
11.58 852.0000 1007.0000 1027.0000 75.0000 ""
12.39 847.0000 1007.0000 1179.0000 72.9100 ""
14.12 2263.0000 1033.0000 1231.0000 50.0000 ""
15.37 1705.0000 1033.0000 1827.0000 49.0500 ""
16.39 4060.0000 1033.0000 1488.0000 45.5600 ""
17.65 3865.0000 1033.0000 1994.0000 39.0000 ""
18.67 4996.0000 1033.0000 1725.0000 38.8600 ""
20.17 4716.0000 1025.0000 1185.0000 50.0000 ""
20.97 1807.0000 1025.0000 1037.0000 75.0000 ""
22.23 1026.0000 1025.0000 1020.0000 75.0000 ""
23.50 840.0000 1025.0000 1022.0000 75.0000 ""
24.75 850.0000 1025.0000 1022.0000 75.0000 ""
26.25 849.0000 1009.0000 1021.0000 75.0000 ""
27.52 848.0000 1009.0000 1022.0000 75.0000 ""
28.94 851.0000 1009.0000 1023.0000 75.0000 ""
30.20 849.0000 1009.0000 1023.0000 75.0000 ""
31.22 850.0000 1009.0000 1023.0000 75.0000 ""
32.27 847.0000 1009.0000 1254.0000 50.0000 ""
33.30 1166.0000 1009.0000 1026.0000 75.0000 ""
34.55 1975.0000 1009.0000 2054.0000 40.0000 ""
35.80 2917.0000 1009.0000 1080.0000 62.6000 ""
37.05 1038.0000 1009.0000 1021.0000 75.0000 ""
38.80 832.0000 1012.0000 1023.0000 75.0000 ""
40.07 851.0000 1012.0000 1021.0000 75.0000 ""
41.10 853.0000 1012.0000 1021.0000 75.0000 ""
41.91 849.0000 1012.0000 1022.0000 75.0000 ""
42.94 852.0000 1012.0000 1021.0000 75.0000 ""

 

[MazCinq]

@sussexa how do I get the graphs from MultiECU to here???


I'm going to go for a drive and log the data and also put it into limp mode to see whats going on.

 

[sussexa]

You can upload the excell file direct or do a screenshot of mes graph and save in paint as png example as pic and upload here direct as an atatchment.
or open up file in excel and insert a graph in excel and I usually screenshot that into paint and save as pic
im not that computer savy theres probably a better easier way, but I know how to do it this way.
Il have a look if i have vnt maps for the 115 anywhere, also would suggest a boost leak if vnt is higher than expected to make boost, also i would expect maf values to be higher than expected for actual boost, eg maf is seeing actual boost airflow plus airflow for missing air from leak.
edit
not sure what conditions that log was above? was it parked up just revving ? the actual boost doesn't go up at all ? does your boost gauge register any boost.
even no load reving like that id expect to see 1100mbar or more, you will never see desired values as under no load but I think 1033mbar was your highest value.
to keep the logs short if you have to screenshot graph, do 3rd or 4th gear, find quiet road and full throttle from below 2000revs up to whatevers safe I normally cant get over 4000 on the roads.(or see much point going over it)
revs, actual boost, actual maf , total fuel
revs desired boost, actual boost , vnt%
should help diagnosis

 

[MazCinq]

well, I just took it for a run along the motorway and did a graph of boost, desired boost and RPM and as I went to hit save my session timed out and lost it.


plus notes, it now no-longer jumps into Limp mode, I held full throttle for a good length of time and no signs of it wanting to pop into limp mode, it was also showing on my boost gauge a steady 0.9bar with the odd spike of 1.1bar at around 2.5k. It would appear I was suffering from a stuck open EGR as the smoke has drastically reduced too. wish I had blanked it sooner.


I will take it out again for a shorter run and get another map.


what four parameters should I put on to watch for a signs of boost leaks???

 

[MazCinq]

not sure what conditions that log was above? was it parked up just revving ? the actual boost doesn't go up at all ? does your boost gauge register any boost.
even no load reving like that id expect to see 1100mbar or more, you will never see desired values as under no load but I think 1033mbar was your highest value.

Yes it was parked and just revving so no load.


even on the run I just did, I had a few glances and boost was never near desired pressure at all.

 

[sussexa]

ive mentioned a few parameters to log above(editing as you were posting probably)
here is example ofhow I add most graphs lately

then ill expand to full screen, screen shot , copy just the graph in new file in paint ie trim just the graph, save as( details here will help you find it later, I usually do date plus conditions or test reason), then add here paperclip (attatchments)
and end up as

 

[MazCinq]

Cheers for your help, I will log it tomorrow as I have had enough of cars today, just had to pull the head off a 2.3 galaxy dam horrible cars.

I will log what you recommended and post the graphs tomorrow.

 

[sussexa]

ok fount that vnt % map
so here with boost map to make easier to see if all is as should be (or close enough)



theyl come in handy for others one day hopefully even if your issues sorted

basically your max boost should be say example 2500revs full fuel 2155mbar
to achieve this boost at 2500revs the vnt % should be around 44%(if I have the right map)
if for example the vnt is adjusting itself to say 55% 65% to achieve max boost at 2500revs it might suggest either vnt issue or a boost leak.
likewise if you were getting actual boost or above with only 25% to 35% at 2500revs it might suggest vane or vnt issue(sticky stuck ) or even a duff map sensor overeading(not likely but possible)

 

[MazCinq]

Here is what I got on the run out. Revs,Boost, Desired boost and Maf Quanity


I will do another run soon and get the VNT figures along with fuel pressure and rpms again, do I stick actual boost on too??

 

[sussexa]

just try to get one long acceleration into the log like mine on last page, unfortunately due to sample rates etc with long logs and slow refresh/sample speeds you end up with spiky logs and also sometimes the peaks are out of sync to each other.
from those logs at least its definitely looking like a boost leak somewhere and now your egr is blanked theres only a few hoses to check in and out of intercooler most likely turbo to intercooler.
ive put a few figures on here

id expect the calculation to equal close to 2
using desired boost still doesn't work out at 2 I suspect as maf is high so works out 1.8
but using actual boost works to 1.5
I suspect the vnt will be going pretty high to try to create boost looking at those maf figures which are pretty high at nearly 1200mg/I this is enough maf for near 2400mbar actual boost so id say its a fairly big leak if real values.
of course the maf could be overreading
the map sensor could be under reading (you can check this with your gauge now is 800mbar a likely max boost your seeing on your gauge if in psi its only 11-12 psi
if your seeing more like 16-18psi max on your gauge id say map sensor
but low boost and high maf suggest boost leak

revs , desired boost , actual boost and vnt%
and
revs ,actual boost, actual maf and vnt%
will help confirm and also help confirm you've sorted it later.
I would recommend doing this before you check for leaks just so you have data to compare after looking for a leak.
find a quite road stick in 3rd or 4th get to say 1800revs start log and floor accelerator all the way as long as you can to above 3000 will do, no part throttle or on and off throttle.
it it then repeatable also in mes you can pull up a tag line that will list actual values at that line like this

and don't forget you can do the scale ie x5 change to x20 and it will look a bit better for the screen shot way of doing it
as in mine above id expect vnt% to drop as the revs and boost increase all the way up till you let off, with a considerable boost leak id expect to see vnt% possibly not dropping very low or go low then start to rise again as boost tops out.

 

[MazCinq]

Thank you for that, I will head out in abit for a Motorway run and get the graph like you suggest.


Boost leak is highly possible and really wouldn't surprise me due to the damage that has been done to this car at some point.

 

[MazCinq]

sussexa Sorry its been slow but I kept forgetting to take my laptop out with me lol.


this is the graph you suggested I take, I wasn't 100% sure which Parameter was the VNT% so I guessed it was the Boost Solenoid% one, from what you have already explained in previous posts its looking more than likely I have a boost leak, is my thinking right here????

 

[sussexa]

ive marked a few points on that log( this is good log , much more usefull)

point A = the most likely point that the boost open loop closed loop control point switches over,
prior to A, reading vnt % from internal ecu map sets turbo to that not adjusting anything on the actual boost value.
after A , using the actual boost value and compared to desired boost works out its under boosting so starts to increase the vnt % to try to achieve desired boost.

point B= matches the vnt switching point and suggests that although the actual vnt% is now increasing , the real actual boost value drops.
this suggests that the ecu may be cutting fuel due to the fact things are not controlling ?not sure

point C= the ecu is taking more drastic action on the vnt and increasing it much more to try to match boost desired
until point D where it stops going any higher
of course where the vnt has drastically increased the actual boost does not appear to increase much at all.

so if your happy the vnt boost solenoid , turbo actuator and turbo vnt vanes are working as should with full travel all the way to the stop screw on max spool(idle 75%)
then yes I suspect you have a boost leak
during the track day photos I see a bit of black smoke in one photo
https://www.fiatforum.com/attachment.php?attachmentid=154437&d=1430996356
looks to be short of air / rich black smoke
also suggesting real boost leak rather than sensor issue aka boost sensor reading low .

overall how did it perform on track ? did it feel lacking grunt ?or ok looked like you enjoyed it.

 

[MazCinq]

I had lots of fun but the car was well down on power and was struggling to beat 85mph along the bottom straight on cadwell park, the straight in the pic, as you can see from the pic I had plenty of run to get up to speed, the Clio's were hitting 130mph I heard one lad saying. I would have expected 100 at least considering the corner speed of around 50-60mph was achieved coming out of this corner.


it was also popping into limp mode. Error code was Overboost Solenoid, in the descibtion it said it was under reading which again would suggest to me its leaking boost.


Oh and the smoke, yeah, there was lots of that lol

 

[DavidNL]

Hello Members..
Today I was at the Fiat garage I had a MAFF last week I did this myself.
Problem not solved.
So I went to the Fiat Garage Pressue was oke no leakage.
The only issue was to check the ECR and yes this had a leakage in it so they blocked off the ECR.\
Saddly my fiat scudo 2.0 JTD Van feel as if its lost accelleration and power.
It runs great and the turbo is working they say.
For me I feel its lost that Boost it had that kick.

They did not know what the problem could be.

Can anyone advice me please.... already 300 euro gone and problem not solved.