another update, i managed to replace the precat bank 1 lambda sensor. much easier to get to than bank 2. reset the adaptations and relearning atm. we'll see how it goes.

also do not buy these sensors from anywhere except the dealership. euro carparts gave me the wrong one and the car was basically beached for 2 days till LR managed to get some in stock since I did the change Sunday and by time i realised my problem parts department were closed.

i still had 12.5% long term fuel trim in park at idle before the adaptation clearing so we'll see what this does. everything points to a vacuum leak but smoke test shows nothing.

am sure eventually it will trigger a lean code but it does it so slowly it feels like that its a really small leak. some also say it could be the cats. Its actually a sport

Not anymore, 4.4 TDV8 now

wouldn't mess about with it until you can do the other sensor.

You can get them from other places they are just dense specific sensors - I ordered mine from the US I think they were £100 that way and are fine - identical to the old ones I pulled. Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

ive got both sensors with me, its just bank 2 is an absolute monster to get to. this would also provide a clearer picture if the new sensor has made a diff, because i can compare bank 1 vs bank 2 directly then, new vs old. Its actually a sport

Not anymore, 4.4 TDV8 now

I think I hate this car.

My trims are still bad haha. All pure petrol, since my last post I swapped the piping at the back of the charger, rebuilt the manifold atleast twice. Changed the fuel filter and fuel pump. Fuel injectors cleaned and seals replaced

All gaskets replaced with above, I now finally have adaptive fuel trims to look at

Is it popping up lean codes?

Have you some coils and o2 and genuine maf? If not do them all for one bank and see if any improvement? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Also I’d join a Jaguar forum for specialist issues like this a popular one as our engine has many many applications and a far bigger user base in these - obviously feed back on here if they help you  Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

dingg1 wrote:

Is it popping up lean codes?

Danwilderspin wrote:

Have you some coils and o2 and genuine maf? If not do them all for one bank and see if any improvement?

Everything but the coils, but I'd assume if there was a problem in combustion the subfeedback would show it.

I did actually check the jaguar forums here:

https://www.jaguarforums.com/forum/general...760/page2/

am literally outta ideas tbh. i wouldn't even mind taking her to a mechanic but people see the lpg and get scared off very quickly. Its actually a sport

Not anymore, 4.4 TDV8 now

If it aint popping codes you are worried about nothing, just drive and enjoy.

The control system is capable of keeping within the safe parameters...

If you are driving it on petrol Dingg is probably right but if you'd like to drive it on gas id want those a bit lower, I was getting rich codes with bad coils actually so that won't be your issue.

TBH mine is not perfect I don't think they are ever going to sit at 0 on both trims, id be interested to know what your idle is like from cold? mine is sometimes not quite as silky smooth when its cold as it usually is... seems to be a few on here that have the same thing,,, Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

from cold its actually pretty banging. smooth, no issues. but yeah I do want to run her on gas which is why am trying to fix the trims. Its actually a sport

Not anymore, 4.4 TDV8 now

Do you get lean codes when its running on gas?

It will do yes, the gas pushes the trims too far Its actually a sport

Not anymore, 4.4 TDV8 now

fair enough mine are floating around 5-10 last time I looked and I was happy as like ding said these aren't highly refined engines they are big brutes they are never going to be bang on... id love it to be 0 but I think my quest would cost a fortune and would make it one of the only ones  Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

id be happy with 5-10, but 17 is ridic Its actually a sport

Not anymore, 4.4 TDV8 now