Yes he will be voted out next time of course; Main problem is this new ULEZ expansion will cost £250M+ in infrastructure alone - and so be difficult to reverse (ie. even if there is a regime change next time). Seems their last expansion - out to the N/S Circ. - was just not as lucrative as expected (because too many conformed !) and so 'only' generates £50M p/a. Thus the net had to be cast wider - and this new Zone is projected to 'generate' another £100M p/a.... The other key point that many don't seem to realise is that any/all such revenue primarily depends on folks NOT conforming of course. (Plus the New fines are planned to be £90/£180). Obviously 'pollution' is not as reduced as claimed either - eg. all one has to do is pay £12.50/day and then you can drive around in the Zone the whole day....
The Mayor (Sadiq Khan) has now decided to extend the ULEZ to the whole of Greater London next August; It's 'all about pollution' (apparently) and nothing to do with ££/depleted TfL coffers (of course)... A Consultation showed that ~70% of folks here were against it - but what do they matter ? Never mind though.... Dubious stats abound ... eg. Khan quotes figures showing the reduction of NOx by 30% in Greater London and 40% in Central London thanks to ULEZ; Too bad those figures are from 2013-2019 - and so before ULEZ though ?!.........
PS: When the Consultation mentioned above did not show what he wanted Khan just commissioned another one which showed folks do like ULEZs: He only asked ~1000 people ....... that's about 1 in 10,000 of course....
PC38: As others have remarked It's definitely much more complicated than mere RPM calculations .....
This has the main points: https://www.gov.uk/government/publications/20-mph-speed-limits-on-roads
Lots of Studies too performed over the years, eg. see ~ p192 in the second (technical) report there:
14.6. How do environmental outcomes compare in 20mph limits
and zones?
14.6.1. Air quality
Section 10.4 shows that air quality in 20mph limits can be affected by vehicle speeds, driver behaviour, and
volume of traffic.
Existing evidence suggests that vehicle emissions in 20mph zones may be adversely affected by changing
vehicle speed and acceleration rate (Boulter and Webster, 1997, cited in Grundy C et al., 2008). Although
vehicle emissions are usually less at lower speeds, emissions may increase in 20mph zones as vehicles use
more fuel to accelerate between calming measures.
Relatively few studies have attempted to quantify the energy and environmental impact of traffic calming
measures, and the results are mixed results with regards to the impact on emissions (greenhouse gases and
air quality).
• Pharoah (1991), cited in Ahn and Rakha (2009), found that traffic calming measures with smooth and
low speed driving in a high gear may result in relatively low emissions and that the effect of traffic
calming strategies on air quality depends on how the scheme influences both the average speed of
traffic and the amount of speed variation. While some studies found that traffic calming measures
benefit air quality, several concluded they increase vehicle fuel consumption and emissions.
• Litman (1999), cited in Ahn and Rakha (2009), studied the benefit and cost of traffic calming measures
and concluded that traffic calming strategies that reduce traffic speeds and smooth traffic flow can
generally reduce air pollution, while those that increase the number of stops may increase emissions. He
also found that when traffic calming reduces vehicle speeds from 50 km/h to 30 km/h for an ‘‘Easy
Driver,” savings in CO, HC, NOx, and fuel consumption in the range of 13%, 22%, 48%, and7%,
respectively, are achievable. In the case of the ‘‘Aggressive Driver” savings in CO, HC, and NOx in the
range of 17%,10%, and 32%, respectively are observable with increases in vehicle fuel consumption in
the range of 7%.
• TRL research undertaken by Boulter et al. (2001), also considered the effect of traffic calming measures
on air quality. The evidence reported that the mean emission rates of carbon monoxide, hydrocarbons,
nitrogen oxide, and carbon dioxide from petrol non-catalyst, petrol catalyst, and diesel cars increased by
up to 60% following the introduction of traffic calming measures. However, it was estimated by TRL that
the increased emission rates were not expected to lead to poorer local air quality.
• Daham et al. (2005), cited in Ahn and Rakha (2009), simulated braking and acceleration events to mimic
speed humps by driving a normal road using an on-road emission measurement device. He found that
speed humps increase HC, CO, NOx, and CO2 emissions by 148%, 117%, 195%, and 90%.
• According to Williams (2013), measures with the least detrimental impact on vehicle emissions are those
that induce the least variation in speed. Emissions were monitored on 10 routes with a range of different
traffic calming methods (vertical deflection, horizontal deflection and psychological). Vehicles were often
seen to exhibit a greater variability in speed on links with vertical deflection than those without; however,
the impact of such traffic calming features was not thought to be as large as that of other traffic
management features, such as pedestrian crossings and signalized junctions. Williams (2013) also
shows that a higher proportion of time spent accelerating and decelerating, is likely to be associated with
increased particulate matter associated with tyre and brake wear.
So, 'big shock' - Resultant Emissions Levels also depend on just how we drive in these 20MPH Zones... !
Observing folks 'interacting oddly' with speed humps, accelerate/brake/accelerate/brake etc illustrates that
issue particularly well, most notably when that acceleration/braking is unnecessarily harsh/hard ?!
Yes, the Nano is highly versatile but even it has limits !
https://www.nanocom-diagnostics.com/uploads/downloads/P-38-%20Lucas%20EAS%20ECU%20Guide.pdf
Sounds like a wiring issue, ie. if not the switch then may also be at the EAS ECU (as the C117 connector can be vulnerable to damage as it is under the passenger seat) ?: Read this and note PIN 15 !
https://rswsolutions.com/index.php/p38a-eas-system/180-p38a-eas-electronic-control-unit
Just don't press it whilst sitting on the seat =>> Whoosh and a parachute !! (only if you have a sunroof, obviously....)
OO7 never had a P38... he had a Walther PPK....
Seriously - what happens if you press it with the engine running ?
Don't think that it is a 'Factory Fitted' item....
so maybe someone had fitted a switch to turn their (old type) Alarm Receiver on/off etc ?
Richard: Thanks: Briefly, some clarification:
That 'only £200 cold water box/fan' nonsense is of course 'well dodgy' - probably as far as the ASA is concerned of course; You may as well just fill a hot water bottle with ice water.... ?
By proper A/C above I probably should have said "proper" ( ie. with inverted commas ) - simply as it has cold out one end and hot out the other.... and that is is at least externally vented
As for the 'heat pump / conditioner' I mentioned without external box it was something very similar to this (and only 1K fitted ...): https://www.appliancesdirect.co.uk/p/a1%2fiqool-smart12hp/electriq-a1iqoolsmart12hp-air-conditioner
Of course I agree that an external box will be (functionally) best, again it is just that aesthetics certainly affect folks' buying decisions.... not just my neighbours. Ask a woman !? Fan noise is key too. Some expect if to be almost silent "like the one in my office building..." (!!)
As BrianH said New Builds/New Regulations may mean house design needs to change.... along with expectations.
The main point is that there is definitely a real need for Customer/Consumer education on all this though: I have lost count of the number of folks asking me questions like 'why their whole garden needs to be dug up' for a Heat Pump Installation...? usually because they have (only) heard about Ground Source kit: Perhaps the BBC could oblige instead of all their celebrity baking/dancing/etc twaddle; I won't be holding my breath.....
Lgpc: As a fixed A/C installation does not have the advantage of forward motion (ie. cooling air over the condenser so you need a big fan instead, as you mentioned) then an electric motor of 1 or 2 kW would probably be needed (or say about 2HP in old money) ?
Your usual excellent techno-commercial intro/analysis: Thanks Richard !
'For my sins' I have discussed such issues - or at least tried to - with local Council officials and even MPs; Almost universally they seem unable to grasp the basics but are 'happy' to implement whatever "the Law/Rules dictate/decide" of course... Oh dear: Might send them your summary instead now though....
In the meantime some of my over-heated neighbours are happy it seems to buy a big plastic box with a fan in it.... merely cooled by 10L of cold water. That's TV ads. for you though, and 'only' £200 (!). A few have the free-standing (proper) A/C units with a tube out of the window (but then they panic about night-time security). Some even have A/C with an 'ugly' external box.. Accordingly the type of heat-pump with large vents through the wall (ie. nothing external) seems ideal but even then they think an enclosure 1X0.5X0.5m is 'too intrusive'... There is definitely a shift in such thinking since 40C hit us recently though... as aesthetics 'go out the window' (!) when folks can't sleep.... ?
Richard - a serious suggestion - and I know you are busy (and also on here too..) but how about starting a Thread or even a blog about all this.... ?
Background; I ask because so many folks seem interested in Heat Pumps but are clearly confused about the types and advantages etc.
-Nothing new in all that of course, Using PVC and then sell 'excess' power back to the grid (and dodgy providers as Ofgem did not regulate them properly... ); Similarly with the move from "Conventional" boilers to expensive Condensing types (not as reliable and not that 'better' overall either of course) and now many Heat Pump vendors abound (with multiple mistruths, like "only 10K guv" but not mentioning the much bigger rads needed and/or underfloor arrangements, plus the vital insulation improvements needed either. (This with a backdrop of 25% of our housing stock being solid wall too. Folks round here paying up to 20K to have rendered foam stuck on their walls). Whatever folks do/add/change 'Payback Periods' of 20 years or so are not uncommon !! Better stop there...
Anyhow, energy rip-offs rant over.. anyone else interested in this idea ?
Indeed Richard, Gas->Liquid as opposed to Liquid-> Gas - I knew I should have just posted a diagram or a suitable link instead ?! eg. http://blog.autointhebox.com/what-you-dont-know-about-your-automotive-air-conditioning-system.html
JCMLuimini: Like Richard I don't know just how the system could apparently show different vacuum/N pressure characteristics between the High and Low sides either... unless, as he suggests. there is a blockage of some kind present...(?)
Now, referring to your original thread, ( in Oily Bits / https://rangerovers.pub/topic/3011-air-con and all your replacement parts ) it's bit of a long shot but (new) A/C components are often supplied with protective plastic plugs in the pipe ends / connectors etc of course (?)
EDIT: I see you started (yet) another thread about this JCMLuimini and that your own leak was actually 'obvious' too ?!
PS: "You're welcome" !
The simple answer to that is - just like when a Vacuum (test) is deployed - ALL parts of the system are effectively 'reached' so to speak, and similarly if you use Pressure instead. Unlike refrigerant in a working system these is no Gas/Liquid phases involved for 'inert' gases of course.
(The 'high pressure' side originates from the compressor (as gas) which reduces through the Condenser/fan as it cools (to liquid) but if there is a "divide" per se that could be considered the Expansion Valve... and it is then the Liquid/Gas transition in the Evaporator that produces the cooling - if that helps..).
As a 'rule of thumb' it is always best to do anything on/via the Low Pressure side of course
Incidentally - again considering the possible size of your leak - I really do hope you are not planning to use dye when you pressurise with Nitrogen !
Well KCR that partly depends on just where the leak is of course, but with such a big leak this could well just 're-decorate' the inside of the car/engine compartment - with bright fluorescent dye spraying everywhere ... ?
Better to use compressed air and spray soapy water on the system as we do with EAS leak-detection ?
Back with the vac. method how about a smoke A/C leak detection approach...
Finally yes forcing the compressor/clutch to run in order to add R134/Dye can work but again with a big leak might consume very large amounts of R134 ?
Update: First of all the nano "wheel rotation speed" facility is actually very limited on pre-99 Wabco-C units (as it stops communicating once the wheels exceed 1.6mph.... ): https://www.nanocom-diagnostics.com/downloads/preview/wabco-c-type-p38
-However when I first read those speed 'inputs' with the nano (for some reason) it gave Front Right/Left & Rear Right/Left values of 4/1 & 2/2 (kph) respectively which may/may not have been significant.. !? Anyone else done/tried this ?
Some more "fast/straight hard braking" cycles later therefore the symptoms improved further....
I have thus decided - rather that to just 'clean up the brake components' - to replace discs/pads,
starting with the rears...
Thanks for all your input chaps, much appreciated !
For clarification the effect is fairly slow - about 2 pulses per second but does not vary very much with speed. That said I took it out for some speed/brake cycles and it changed slightly... I'm not sure if that means it could be corrosion/dust on the pads/discs/etc (?) Has to be something mechanical though, as my P38 probably just thinks I am on ice or a slippery surface so does not report a 'fault' as such (?)
My nano is on loan at the moment but over the weekend it will be returned so I can then monitor the (individual) wheel speeds with it to see if there are any discrepancies. Either way it is probably time for a strip-down/clean up of brake components if the pulsing persists/worsens .. Might even do a 'run-out' check on the discs too and see what that shows.
-As an aside if anyone who has not experienced it wants to feel what ABS feels like 'in action', ie. without all the tricky stuff (ice etc) - just put different sized/profiled wheels on the front and back (an inch diameter overall is usually enough) !
Thanks Richard, Yes it's definitely an odd one, nothing happens on the dash either !
EDIT: Just read elsewhere brake pads may be binding (unevenly) - but that should still show up as a fault...
Oddly the MSV2 states "all four wheels are rotating evenly"....
Will try some 'drive rapidly in a straight line and brake hard' cycles as per the other info I read: Not exactly ideal if the brakes are 'iffy' of course; Will report back ....!
Anyone had this ? Feels like 'cadence braking' is happening... happens at low speeds too
Suspected the ABS (eg. a sensor) but no faults showing via diagnostics !
('95/TRW)
UPDATE: Hurrah, my "ecoOBD2" has arrived, and really I could not wait to try it !!
Sure enough when you plug it in and push the button the three coloured Leds flash (at random..): Great, I can't wait to save fuel either... !
Oh no, I opened it up and it actually just connects to the Eth. and Power pins... Hmmm, perhaps it uses 'magic' then ?
Even worse it seems to just have a 555 Timer chip within, although the designation on it was removed......
perhaps to stop folks plagiarising this amazing money-saving unit ??
but wait... on the 'instructions' it states:
"ecoOBD2 will recognise your vehicle and your driving habits, after around 200km/150miles driving and thus ecoOBD2 will adjust itself to match your car perfectly for more fuel saving "
Interestingly on the Customs Label it is described as a Scanner(SH-ELM004-1X)...
Difficult to tell though as the wording is small and it might actually say Scammer ?
Probably just as well then that I just planned to remove the PCB and use the box for a Plug-In Voltmeter instead then.... ?
'Nice' they provided the Worlds' Smallest Xmas Tree lights like this though.
Might affect 'back pressure' but that far 'downstream' the effects of changing to one pipe should be marginal: No major 'function' otherwise so maybe RR designers just thought twin pipes looked 'cool' ?