Diagnostic data help, poorly lean V8

could someone have a look at the following data and help me out please, i know im down a bank and i need a few pointers, not a petrol guy im a diesel / plant man. id really appreciate any constructive help please.

I have a 2004 range rover v8 4.4 vogue. originally had fault code p1174 - system lean bank B

ive scanned and took this live data at idle. much appreciated for any help given

cheers
lee
---------------------1 of 1 Frame---------------------
Engine Speed 658 rpm
Air Flow Mass 42.9 kgh
Throttle Position 14 %
Driver Demand 0.71 V
Intaker Air Temp 66 °F
Coolant Temp 100 °F
Radiator Coolant Temp 63 °F
Road Speed 0.00 mph
Battery Voltage 13.56 V
Purge Value 0 duty %
Lambda Control Bank1 1.00
Lambda Control Bank2 1.00
02 Bank1 0.39 V
02 Bank2 0.45 V
Target Idle Speed 900 rpm
Engine Troque 22 %
Idle Control Active
Idle Control Active Active
Additive Adaption Bank1 0.000 %
Additive Adaption Bank2 0.000 %
Multiplicative Adaption Bank1 0.999 %
Multiplicative Adaption Bank2 0.999 %
O2 Heating Pre Cat Bank 1 0.28
O2 Heating Pre Cat Bank 2 0.28
O2 Heating Post Cat Bank 1 0.14
O2 Heating Post Cat Bank 2 0.14
Injector Timing 0.745 ms
Cam Position Bank 1 7.020 °
Cam Position Bank 2 4.743 °
Air Leakage 6.9 kg/h
Equalisation 1.000
Substitute 0.844
Throttle Position Not Learned
Kick Down Not Active
Adaption 1 -8.351 °
Adaption 2 -6.390 °
Adaption 3 -6.401 °
Adaption 4 -8.612 °
Adaption 5 1.414 °
Adaption 6 1.906 °
Adaption 7 2.098 °
Adaption 8 2.098 °
Full Load Not Active
WANOS Bank 1 67.45 %
WANOS Bank 2 67.45 %
Ignition Angle 24.00 deg
Ready Pre Cat Bank 1 READY
Ready Pre Cat Bank 2 NOT READY
Ready Post Cat Bank 1 READY
Ready Post Cat Bank 2 NOT READY
Closed Loop Bank 1 Active
Closed Loop Bank 2 Not Active
Pre Cat Heater Bank 1 Not Active
Pre Cat Heater Bank 2 Not Active
Post Cat Heater Bank 1 Not Active
Post Cat Heater Bank 2 Not Active
Off Time Bank 1 0.300 s
Off Time Bank 2 0.300 s
O2 Heating Period Bank 1 0.2 s
O2 Heating Period Bank 2 0.2 s
High Purge Load Not Active
Engine Roughness Cyl 1 -7.278 us
Engine Roughness Cyl 2 -6.953 us
Engine Roughness Cyl 3 -2.523 us
Engine Roughness Cyl 4 -3.739 us
Engine Roughness Cyl 5 3.549 us
Engine Roughness Cyl 6 6.078 us
Engine Roughness Cyl 7 4.843 us
Engine Roughness Cyl 8 9.243 us
Knock Threshold Cyl 1 10.156 V
Knock Threshold Cyl 2 12.890 V
Knock Threshold Cyl 3 9.375 V
Knock Threshold Cyl 4 13.672 V
Knock Threshold Cyl 5 8.594 V
Knock Threshold Cyl 6 9.765 V
Knock Threshold Cyl 7 14.844 V
Knock Threshold Cyl 8 9.765 V
Immobilisation MOBILISED
Park/Neutral P/N
Purge Duty Cycle 0.00 duty%
VANOS Bank 1 71.37 duty%
VANOS Bank 2 72.94 duty%
Aux Fan 92.94 duty%
Fuel Pump Active
Electric Thermostat OFF
Comfort Start Not Active
A/C Commpressor Not Active
O2 Ready Pre Cat Bank 1 Active
O2 Ready Pre Cat Bank 2 Not Active
O2 Ready Post Cat Bank 1 Not Active
O2 Ready Post Cat Bank 2 Not Active
Fuel Cut Off Not Active
Cat Tested Tested
Purge Tested Not Tested
O2 Pre Cat Tested Tested
O2 Post Cat Tested Tested
　
　

I can see that the MAF reading is high would this just knock out one bank though?

MAF would no doubt affect both banks....

Take the acoustic cover off and try spraying some brake cleaner around the intake manifold where it joins the heads and also the throttle body and rear PCV valve....if there is a noticable change in engine note.....you could have an air leak....failing that, it could be a lambda sensor or two...or the wiring thereto....duff.

Thanks bud, the break cleaner was my job for the morning. Doesn't sound like it's going to be anything too sinister.

So I've got oil on the plug and high readings on #7 is it likely to be a gummed up oil control ring or are valve stem seals a more likely culprit? Gong to try some ATF on the bore for a few days to try and degum the rings first and some fuel additive

Leaking Rocker Cover Gaskets or possibly PCV Valve failure causing over pressure blowing oil through the gaskets into the plug wells....this has been well documented on the M62 engine....and is the most common reason for oil in the plug wells.

In fact it could be the cause of your lean issue too......

Would this show as oil on the plug electrode tip though?? Thanks

No, just in the well and contaminate the Coil Extension Leg thingy....

Oil on the tip of the plug could mean oil is making its way into the combustion chamber....be it via the rings or the valve seals.

Yep that's what I thought. I've put ATF done the bore now and will leave it a day or two to work through then I will try it again see if it's made any difference I'll chuck some top end cleaner in as well for good measure hoping 1. I can free off the gunned up ring by pure luck. 2. It's stem seals worse case scenario.

I think it's weird that only one pot is out though.

ATF on the bore? You poured ATF down the spark plug hole?

ATF is a good detergent and can unstick stuck/gummed up pistons rings.

Grrrrrr said:

ATF on the bore? You poured ATF down the spark plug hole?

Click to expand...

Yep it will soak past the rings and hopefully release the oil control ring if indeed that is the issue ( fingers crossed )