Hi All,

Sorry for multi posting but this is a quick simple question I think (unlike my other post) I have a post cat o2 sensor 1 failure.

Firstly form the uk - is that the driver side one?

Secondly, I have a universal brand new ash 4 wire o2 sensor I bought years ago brand new and sealed. is there any harm using this? the details of fitment are some what vague on the universal sensors, however being a Bosch thought it should be ok? it has two white wires a grey and a black, if people say its worth a shot I will solder and heat shrink it together... Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Bank 1 has the oil filler cap. Personly I wouldnt mess with it and just buy the correct one. Are you sure its faulty ? You should get a steady .5v reading from the rears when up to tempreture if I remember correctly. No7 - 2003 V8 Vogue

They fluctuate between 0.0 to 0.8 - the harder the driving the closer to 0.8 is this bad or good? This seems to be the case on both rear sensors Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Sounds good. .8 is rich so when you give it some I would expect them to go rich. No7 - 2003 V8 Vogue

ok great - if I have done the rocker gaskets, the pcv valve, the oil breather hoses at the back going to the cyclone and pcv - what else could cause a vac leak? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Is it an air leak or a badMAF? I’ve got some known good figure for the Mac somewhere. I will dig them out and post them up No7 - 2003 V8 Vogue

Found them........
Readings with all loads off
600 rpm 17.1 kgh
1500 36.9 kgh
2000 50.2 kgh
3000 72 kgh

IF you have anything different + or - a tad, theres your issue. No7 - 2003 V8 Vogue

Ok..

630 - 13.1
1500 - 35.2
2000 - 45.1
3000 - 70.4

Lower down seems the most out is that enough to upset things? I have some maf cleaner would you remove it and soak in that and put it back in the morning? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Worth a go. Those figure are confirmed against two different vehicles. If it’s under reading then the fueling will be lean. Don’t be tempted by a cheap maf, always buy genuine No7 - 2003 V8 Vogue

My maf is a Bosch only 18 months old I am going to clean it first if not I will try to warranty it as it has a limited lifetime warranty allegedly- any idea what that pipe is? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Right- this may be two problems now...

Here goes,

Started this morning and it ran like crap on idle and I got low coolant warning... I got two litres in but no obvious leak except possibly around water pump. Also a weird metallic sound



Secondly after warmup I turned car back on still idling like crap it had engine light flashing and I got multiple cylinder misfire and had 1-4 individually listed - what would cause this jus on one bank? Also notice the maf was at 16.1 at idle when running bad which is only out from what’s mentioned above - is that still too much? Thanks Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Are you running lpg? It’s not unheard of the vaporiser failing and letting water into the lpg injectors or gas into the cooling system. Try by passing the vap and fulling the plug in the lpg No7 - 2003 V8 Vogue

Hi I am running lpg and I did run it yesterday but when I had these problems I switched it to petrol only to rule it out. Also vapouriser is only 6 months old so hopefully not that. I bravely/stupidly went for a 40mile drive and it drove lovely water temps were fine - swapped to gas 20 miles in again was fine ... any other ideas? Got the maf out there was a little dirt on the film given it a blast of maf cleaner before bed cleaned it up will get it back on in the morning... any ideas to the random metal sounding noise? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Cleaned the maf - started up flashing eml, dirty idle.. went for a bit of a drive ran fine engine light went off... any thoughts? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF