Running VERY rich and IAT

[misha]

No chance....n/a 20v cars didn't had IAT.

Vol-Fcr is Volvo Fault Code Reader.
With it...you can access ALL modules in the car except ECC which still produce flash codes on all 850s ...ecu ONLY if it's M4.4 and it can reset service light reminder.

Re-learn procedure is somewhere in a database...it should be.
If it's not....i'll post a pdf from my computer.

Here it is:
http://www.volvotips.com/index.php/850- ... rocedures/

[xanthefin]

To your original start post little more info. Ambient T. for ECU uses other sensor than what your odometer does, there is two sensors at same location at the front bumper if there is Ambient T. sensor at all as not always been on all M4.4 cars.

IAT sensor you are looking through OBDII (Generic OBDII) Live data is not on Motronic section as there is none. This "OBDII" is made for any car and not just Volvos so its all around section and not divided per car or per model as that would be nightmare to make.

I'm using the Motronic section. It shows large negative values labeled Ambient air temperature. If I use the OBD2 section IAT is blank.

I give that if you using old version and wifi there was typo which did give wrong results like on OBDII.

I'm using bluetooth, and am unsure how to update to a newer version.

Main page shows at top corner under the logo and name version, what it is? You get updates through Google Play store.

You might have different version of M4.4 than me here then or you are missing the sensor just and ECU is using pre determined values when its not in place. If you do scan in service with OBDII standard app does list all the supported PIDs of the ECU what VolFcr cant example for the OBDII live data usage or else. In list should be 0F like in picture below.


What codes (EFI-xxx) you get when you do scan with Motronic selected in the app? Can you send screenshot? It does same way code reading as Volfcr so there is no fancy update if you go that way.



To add misha saying of ECC.. on Volfcr or by this app you can't read Yazaki dash, M4.3, MFI system (LH-jetronic 3.2 & EZ129K), Fenix 5.2, ECC(A/C) or Cruise Control are not reachable on 850 systems.





If i would be you i would go test injectors with app as you can and attach fuel gage on fuel rail.
In app go Service - Advanced - Motronic section to choose Injectors.. and after Ignition turned II fuel pump has run and there is pressure i would test one by one each injector by looking does the pressure drop in the gauge similarly with all Injectors.

Second i would go in Live data to see how O2 behaves in Graph mode as you can look do they behave as like here explained:

And like here with graph

[erikv11]

For 850 cars the 1996 NA is a mixed year, some are Motronic 4.3, some are 4.4. I suggest find out which engine management it has to help clarify the discussion. You used to be able to get that information by looking up the VIN at a Volvo-run website but they took down that link. Perhaps there is another link available now.

1996 turbo are all 4.3.

All discussions aside, I'd still get a junkyard MAF and swap it in. And make sure there are no vacuum leaks. Check the little rubber elbow at the manifold.

[SirBrickWagon]

had a similar issue, soot on the tailpipe and all. it wouldn't be a header leak bringing exhaust gas into the air filter or not registering in the cat? car ran rich when not enough exhaust gas was getting through my cat, so i'm just checking, i could have some insight

[454cid]

To your original start post little more info. Ambient T. for ECU uses other sensor than what your odometer does, there is two sensors at same location at the front bumper if there is Ambient T. sensor at all as not always been on all M4.4 cars.

Yes, I understand. I was questioning it because of the use of "ambient". That's not the correct term in my opinion. Typically, it would be called "IAT" (intake air temperature). I'm not familiar with European cars, so I considered it to be the IAT, and it is, except that my 850 doesn't actually have the sensor, just the sensor for the dash. I'd really like to know why it reports very low temperatures.... -40F to -1XXF. All I can figure is that it's a calculated value

Main page shows at top corner under the logo and name version, what it is? You get updates through Google Play store.

I have version 1.5.2

What codes (EFI-xxx) you get when you do scan with Motronic selected in the app? Can you send screenshot? It does same way code reading as Volfcr so there is no fancy update if you go that way.

I am not regularly getting codes, which is part of my problem. I can try to do a screenshot later. I've never tried that.

Second i would go in Live data to see how O2 behaves in Graph mode as you can look do they behave as like here explained:

I will try to graph it. I've already been looking at the live O2 data, and it's very very low. Measuring 100ths of a volt, rather than tenths.

I think I either have an O2 sending false data, or I have an air leak in the exhaust prior to the sensor.

[454cid]

had a similar issue, soot on the tailpipe and all. it wouldn't be a header leak bringing exhaust gas into the air filter or not registering in the cat? car ran rich when not enough exhaust gas was getting through my cat, so i'm just checking, i could have some insight

Yes, I'm thinking either a bad 02 or an exhaust leak someplace. I wonder if a bad SAS valve could be the culprit. I do often smell exhaust when stopped. There have been a few times where I heard a vibrating noise from the valve, although not recently.

[454cid]

All discussions aside, I'd still get a junkyard MAF and swap it in. And make sure there are no vacuum leaks. Check the little rubber elbow at the manifold.

I'm not sure what elbow you're referring to.

Where is the best place to put a vacuum gauge? I checked one line and it was about 13-14 inHG, but I don't know if that was ported vacuum, or manifold vacuum.

[erikv11]

SAS makes some sense too. Maybe time to get rid of it? Or at least block it off to troubleshoot.

All discussions aside, I'd still get a junkyard MAF and swap it in. And make sure there are no vacuum leaks. Check the little rubber elbow at the manifold.

I'm not sure what elbow you're referring to.

...

In this post viewtopic.php?t=65002, look at the manifold end of "line 3." From the factory there is a hard line there with a rubber elbow connecting to the IM. Very common for the elbow to rot out resulting in a vacuum leak.

[454cid]

SAS makes some sense too. Maybe time to get rid of it? Or at least block it off to troubleshoot.

Yes, I'm considering both options. I'll have more time to dink around with it in a week.

Any idea what the thread on the header/manifold is, where the pipe screws in? I've read "pipe plug" a few times, but I have my doubts about it being NPT.

In this post viewtopic.php?t=65002, look at the manifold end of "line 3." From the factory there is a hard line there with a rubber elbow connecting to the IM. Very common for the elbow to rot out resulting in a vacuum leak.

I didn't know there was a line there. Very interesting/informative thread.

[SirBrickWagon]

had a similar issue, soot on the tailpipe and all. it wouldn't be a header leak bringing exhaust gas into the air filter or not registering in the cat? car ran rich when not enough exhaust gas was getting through my cat, so i'm just checking, i could have some insight

Yes, I'm thinking either a bad 02 or an exhaust leak someplace. I wonder if a bad SAS valve could be the culprit. I do often smell exhaust when stopped. There have been a few times where I heard a vibrating noise from the valve, although not recently.

a common place on naturally aspirated volvos tends to be near the flex joint connecting the manifold to the exhaust pipe. that was my issue, but it sounded rough and loud.