Still Running Rich?

So I have gone back through diagnostic log files from over 2 years now in order to work out why my engine is running rich (Failed emissions and also poor fuel economy) and also black exhaust.

Following graphs taken at different date intervals

RPM, Lambda Regulation, Engine load and injector pulse widths

06/07/14 - Runs at around 0.8-0.9 except when de-accelerating. Still looks like its running rich but plenty of lean.

14/10/14 - Runs at around 0.8-0.9 except when de-accelerating. Still looking rich but again some lean.

05/08/15 - After fitting in March new "universal" sensor. Not really sure what's going on could be "normal" but no real regulation.

12/12/15 - Lambda Runs most of the time at 0.45v. Signal very poor stuck around 0.45v little response.

At this time the "universal" sensor response was stuck at 0.45v confirmed by unplugging and it stays at 0.45v

Decided to fit OEM Bosch Sesnor.

20/12/15 - Fitted new Lambda Sensor. Improved over previous BUT only a very few lean points.

UPDATE:

Changed FPR regulator after issues seen with Fuel Pressure tests. Re run the same trip:

No to confirm the lambda signal I removed it. Fixed it out of the way. Rerun the same drive. Very noisy from the hole left behind.

From the above graphs 2014 was before last MOT and engine seems to be have high Lambda except during de-acceleration

2015 March (03) time fitted "universal" lambda sensor due to emissions failure. at some point from then on sensor started to run constantly 0.45v

Fitting the OEM Bosch sensor on 20/12/15 the sensor has started to indicate rich at around 0.8 / 0.9v similar to 2014 at the later parts of the graph but still with not much rich / lean switching going on here.

SO in summary:

At the first traces some rich / lean cycling fitting universal sensor failed within 6-8 months.

Fitting OEM Bosch sensor improves response BUT still looking rich with little rich / lean.

I have then proceeded in using my USB oscilloscope to check the actual sensor response.

As you can see it is actually rich at 0.8v. Blipped the throttle a few times and saw the response drop from rich / lean BUT not switching enough only on de-accelerating.

So in conclusion:

Diagnostics logs & Scope of OEM sensor show rich.
Unsure if ECU actually switches rich / lean in response to o2

Things to yet to confirm / check:

1. Fuel Pressure Test - Too much fuel-Fuel Pressure regulator / Stuck Injectors - Completed - Fuel pressure decay at full vacuum - Replaced FPR - No difference. Still could be injectors. Repeat tests with FPR.
2. All Cylinders firing - One not firing - Incomplete fuel burnt
3. Find more info on ECU - Does it switch (need another Kombi / Info) - Looks like artificial lean (removed) makes no difference to Injection on time. I am suspecting that this MP9 ECU does not operate a closed loop so the Lambda is just for indication or base level of injection timing.
4. Lambda Sensor - New OEM sensor works fine out of exhaust (Lean) and Rich when in exhaust.
5. Blocked Exhaust - Still could be block CAT or exhaust - Plan is remove the CAT with Lambda in place and check signal. Inspect CAT.
6. TPS - Maybe TPS showing 6.7 degrees at Idle is causing the lack of lean at idle due to the ECU still thinking its open (foot on throttle) - Will need to reset the TPS by checking that Butterfly is actually closed and ECU detects no throttle.