[badgerbrock72]

Hello everyone.

I have a question regarding exhaust gas backpressure, and what is an 'within tolerance' reading.

Using BMWhat app, no error codes are thrown. Car seems to regenerate as expected, coolant getting to 91 or so during normal driving. So far so good.

However, exhaust gas backpressure readings, there are two options in the app, one is upstream of dpf, other is before dpf. Both are reading about the same, fairly consistent at around 1000 hPa (whatever hPa is)

And there lies my question, anyone in the know, know if that sort of reading is ok??

Many thanks for any help

Garry

[Kenebell]

I'd be interested in the answer to this also. Are you using the IPhone or android app??

[badgerbrock72]

Morning,

Im using the android app.

Just after some reassurance that others are getting similar readings, and that i therefore dont have an issue... Or maybe i do?!

Cheers

Garry

[Kenebell]

Morning Garry, I'm using the IPhone app which I believe isn't as comprehensive as the android for monitoring the back pressures. I've read this before but not sure if the iPhone app can measure it????

Car must be stationary and with engine up to temp:
Idle max reading 65mbar
2000rpm max reading 150mbar
4000rpm (max stationary rpm) max reading 250mbar

If it's within these tolerances the dpf is considered healthy.

I'll check mine today and see what readings I get and report back

Cheers

[badgerbrock72]

Cheers that would be much appreciated.

While you are there I've found another measure, again it's in hPa this one is called filtered differential pressure on the particle filter... And this one is reading within tolerance too those readings you posted.

Cheers

Garry

[Kenebell]

So checked mine yesterday and with engine up to temperature the reading for differential pressure accross the particle filter were:-
Idle 13hpa
2000rpm 40hpa
4000rpm 80hpa

(1hpa=1mbar)

I'm pretty pleased with that, hopefully everything is well with the dpf.... Long may it continue....

[badgerbrock72]

Thanks for this - all sounds good then for your DPF hopefully

was that 'filtered differential pressure across the PF' or just differential across the PF - because for me the readings are different?

also did you take a look at the exhaust gas back pressure readings (upstream and downstream of the DPF) - would be especially interested in what you see for those ones. On mine they don't seem to vary much with engine revs.

cheers

Garry

[Kenebell]

Hi Garry,

Just been out and checked the app on the car again. My readings are taken from "differential pressure across the particle filter". I don't seem to have the parameters that you have, I think the iPhone app is limited compared to the android app. I think on the android app you can see far more parameter that concern the dpf. You'll be able to see distance since last regeneration. I have to check my regen using the soot in the particle filter parameter and temperature before the particle filter. What are your pressure readings? Tonight I had 37g of soot in the filter and the differential pressure was higher than Saturday (still well within the limits) so it'll regen pretty soon

[badgerbrock72]

Evening,

Thanks for taking the time to check again, guess the different versions read different params as you say, have you got the official wifi dongle? I bought a cheap ebay one (for example when i run diagnostics, out of the 39 ECU modules i only get 22 responses)

I may shell out for the official one.

My readings for 'filtered differential pressure' are well within tolerance, at idle its about 10 hPa.

Cheers

Garry.