Engine: D5244: D5 Vacuum&Boost Diagnosis - What pressure to expect?

[Konstantine]

Hello dear Elks!

I just got a used V70-II from 2003 and am slowly getting to know it.
It was cheap, and has got some minor Issues. Thus I am starting to
diagnose the Vacuum-System and was about to make a check of the
Boost controls.

Unfortunately i have not found any Information on what pressure/vacuum
to expect in different conditions. Is there some kind of Charts available
somewhere?

Would be very helpful if someone has a hint in the right direction!

Best Regards, Konstantine

[davebb]

Hi if you test boost using the torque app the max boost should be 16-17psi
if not remapped, if remapped it will read between 20-22psi
if over boosting it will still only read 21-22psi as the car only has a 2.5bar MAP sensor, you will not see any vacuum on a obd reader or real boost gauge as there is no throttle body on the car, you do have a vacuum pump for the vnt turbo control, putting a mityvac pump ,on to the car vac pump will read - full scale vac, there is a TCV actuator between the vac pump and turbo actuator, that controls the boost by the ecu,
if you are seeing 21-22 boost on obd reader/torque app
the car maybe over boosting,
you need to fit a real boost gauge to the car to be shore, as if it has had a remap it will be reading very close to that,
to mount a boost gauge to the car you need to drill and tap for a fitting in the boost side of the inlet, the egr mixer pipe is good for this,
Dave

[Konstantine]

Hey Dave,

thanks for the quick Reply!

Unfortunately i do not have any digital testing equipment yet.
Am looking forward to buy a DICE, got Vida already.

And, i also do not have any App-driving interface.
Just an analog gauge for vacuum and one for pressure.

What i am looking for specifically are the Values as following:
-Expected vacuum in Idle AFTER the Motor mounts control valve.
-Expected vacuum before the TCV, during idle, mid-RPM, high-RPM
-Expected vacuum AFTER the TCV, during idle, mid-RPM, high-RPM
...if possible as a chart/curve-diagram.

On the Pressure Side:
-Expected Boost Pressure diagram in correlation to RPM

Thanks for the Hint with the egr-mixer-pipe as a location
for a pressure sensor! Sounds like a good place to put it.
I was looking for a blanking-screw to put a sensor in, but
I guess this is not available...?

And: the Car ist stock, not remapped/tuned etc.

I will post a diagnose chart to get all this Info in one Document
when i am finally done with this.

Best Regards, Konstantine

[davebb]

Hi
at Idle about -26inhg at the vac mount and before and after the TCV and at the turbo ,
vac gets switched off at and above 1500rpm by the solenoid mounted on the air filter ,
like I say to read boost you will need to mount gauge to inlet by drilling and fitting a outlet port,

I hope you can see the 2 files I have added of the Volvo d5 turbo mapping
Dave

[davebb]

the turbo air pressure is in milibar, as 1000milibar is atmospheric pressure at sea level,
Dave

[davebb]

also at full load ,high rpm the vac will go a lot lower as the vnt turbo will be spinning very fast , and will not need the veins to be in max boost
the vnt turbo is controlled by vacuum not pressure like non vnt turbos,
the vacuum at the pump will be high at all RPMs
Dave

[davebb]

This is pic of the TCV MAP
Dave

[Konstantine]

Hey Dave!

this really helps a lot!!! I will make a analog approach,
take notes, read the rpm & Pressure to get a rough
approximation. I am looking forward to buy some pressure
Sensors and install them permanently to get an overview
of the overall values and the performance of the whole system.

Thanks a lot Dave! Cheers, Konstantine

[davebb]

Hi Konstantine
No problem, I like to help, I have a lot of time available at the moment as I am out of work, trying to find some work, I am a prototype wireman,,
I have been trying to get work done on my car as I got a lot of parts for my car over the year, but was not that well, so now I do feel better, I am working on my car but I have to do it outside, I have a 2002 s60 D5 SE,

what is wrong with your car, the vnt turbo,s do get choked up, stopping them working as they should,

This is the fitting I am using for my boost gauge

https://www.ebay.co.uk/itm/10-20X-St...ar=&hash=item0

Dave

[Konstantine]

Hey Dave,
Prtotype Wireman!? Sounds like a Job with Voltage!
I do mechanical prototyping, from cad to mill/lathe to
working whateverweirdthing.

Hope you get good soon, i would not dare to work outside,
got -5°C out there... duh...

So, the Issue... I saw the Video from SiRobb,
Volvo D5 Engine Popping Noise Cause and Cure:
https://www.youtube.com/watch?v=QHLyubTrIQ8

And i have the same sound, BUT, it only stopped when I
unmounted the Brake-Vac.Hose! Not when I got the Leak
plugged.

Also, I have some suboptimal cold starting behaviour,
and a bit clonky cold engine idle.

Otherwise it runs like a charm.

But before i brake my brains thinking too much, I will just
get some readings, and maybe then it will be easier to
understand the culprit.

Suggestions, Ideas?

Cheers, K.