VW Golf MK7 Estate, GT spec, Tungsten Silver, 1.4TSI

May 2018, Part IV

The final problem that I have been sorting is the A u t o p o l a r unit that I purchased & received back in March. The reason for install now is that I had the produce sent out to me by accident in March & the software was not 100% then. So I finally got the go ahead from the UK importer, whom I purchased the unit from & started fitting it on Monday 14 May, & basically things went downhill from then!!........ All posted here from post no4:-

https://www.golfmk7.com/forums/showthread.php?t=40119

The main bulk of the info is in this post here:-
https://www.golfmk7.com/forums/showpost.php?p=634885&postcount=28

The unit was sent back to the UK importer & I'll de getting my money back! Second aftermarket product I have had to send back recently as not as advertised/ badly developed IMHO!!..

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Also when I was fitting the A u t o p o l a r unit under the dash I found the cause of one of the “creaks”. Drivers side UK, Passenger side NAR there is a big wrap/loom of cables attached to the rear of the main horizontal metal crash tube behind/in the dash, & about 1ft in from the door. This loom is attached to the metal tube with a small plastic “T-fir-tree” fitting which is loom tapped to the bunch of cables. Unfortunately they used very little tape & the loom had become detached from the “T-fir-tree” & so was moving around “creaking”. I used a big 9mm wide cable tie & covered it in 3 layers of fabric loom tape to cushion/protect the wires, & cable tied it around the whole loom & the metal tube. Not too tight, but tight enough to stop it moving! All nice & quiet now!!......

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On a final note the AP unit does gain accurate data from the ECU’s we have in these cars (main reason for originally purchasing). It displayed the actual Torque as Nm, which is also a parameter in VCDS as this is directly read from the engines ECU. It also calculates BHP from using the Nm, Revs, MAF, MAP, injection, etc., sensors. Results? Well in the short time I had it I managed to see:-

167bhp.....267Nm...........
Stock is 140PS (138bhp) & 250Nm

All the 1.4lt VAG engines I have had, I always got way more out of them due to the petrol I use & various other simple important tweaks, without having to resort to re-maps, & this engine feels this fast & way more power than the stock one I get as a courtesy car! I have done some research on the accuracy of these figures gained from the engine ECU, & apparently if the engine ECU is accurate/complex like ours is & has loads of sensors, like our does, then these calculations are far more “true” than most wheel dynos as read direct from the engine!

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On a further side note, when I did the drive to re-calibrate the ACC radar unit as describing in the above link, quote:-
“Went for a nice long drive (110miles), had to do 15miles to get to the main dual carriageway road which I mainly use the ACC on as its 60 & 70mph & with average speed cameras!! So did about 80miles all told on 60 & 70mph roads following trucks at 50mph & cars at other times doing 70mph.”

Looking through the driving data in the MFD, I noted the following:-
Trip distance = 110miles
Ave speed = 49mph
Ave mpg = 50.2mpg...!!!

So that’s 50.2mpg (UK), 41.8mpg (USA), 5.63L/100km...!!!!!....

My aero mods & GTE intake etc really do work!!!..WELL pleased!!!

Oh & read back at the start I think I mentioned the fact that over 3000miles I did calibrate my MFD reading compared to brim to brim using the same fuel pump etc. & adjusted the MFD via VCDS, so within 1% accuracy!

[QUOTE

Looking through the driving data in the MFD, I got the following:-
Trip distance = 110miles
Ave speed = 49mph
Ave mpg = 50.2mpg...!!!

So that’s 50.2mpg (UK), 41.8mpg (USA), 5.63L/100km...!!!!!....

[/QUOTE]



Distance divided by avg speed doesn’t result in a fuel consumption number... you need to divide the distance by the fuel consumed or replaced when you fill it up to get MPG.


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BostonDriver said:

Distance divided by avg speed doesn’t result in a fuel consumption number... you need to divide the distance by the fuel consumed or replaced when you fill it up to get MPG.

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Click to expand...

You misunderstand....The MPG figure of "50.2mpg (UK)" is taken directly from the "Average MPG " figure shown in the MFD screen....& is accurate to within 1% of manual calculation via brim to brim fills & mileage resets every brim & after doing that for 3000miles & found my MFD was "out" by 7% so adjusted it in VCDS & then again rechecked it doing brim to brim fills & mileage resets...

golfdave said:

You misunderstand....The MPG figure of "50.2mpg (UK)" is taken directly from the "Average MPG " figure shown in the MFD screen....& is accurate to within 1% of manual calculation via brim to brim fills & mileage resets every brim & after doing that for 3000miles & found my MFD was "out" by 7% so adjusted it in VCDS & then again rechecked it doing brim to brim fills & mileage resets...

Click to expand...

Whoops. Misread that as you calculated the avg mpg. Not that it was the value displayed... [emoji850][emoji1360]


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BostonDriver said:

Whoops. Misread that as you calculated the avg mpg. Not that it was the value displayed... [emoji850][emoji1360]


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Click to expand...

No problems...

Then I'll add that I always drive it in sport mode & have 225/24R17 tyres & OEM mudflaps...all of which kill mpg...

And its "just" a 1.4lt TSI...no remap...

The better mpg, increased BHP & Nm of torque, just prove basic mechanical tuning does work if you do it right!....

My 100% stock NAR GSW 1.8TSI (170 hp / 199 ft-lbs [270 N-m]) has done 41.1 mpg (US) on a tank (hand-calculated brim-brim), the highest I've managed yet. It will routinely get 37-39 on interstate runs averaging 65-75 mph. The general consensus, also among NAR owners, is that VW's officially stated numbers are overly conservative. Some NAR owners have dyno'd ~190 whp and ~220 ft-lb bone stock.

southpawboston said:

My 100% stock NAR GSW 1.8TSI (170 hp / 199 ft-lbs [270 N-m]) has done 41.1 mpg (US) on a tank (hand-calculated brim-brim), the highest I've managed yet. It will routinely get 37-39 on interstate runs averaging 65-75 mph. The general consensus, also among NAR owners, is that VW's officially stated numbers are overly conservative. Some NAR owners have dyno'd ~190 whp and ~220 ft-lb bone stock.

Click to expand...

In Europe we don't get the 1.8lt in the Golf....the Skoda Octavia MK3 MQB gets its though in the L&K version. I had a look at one of those..4inches longer than the GSW, & this 1.8lt is still limited by the same MQ250 gearbox...so 180PS (177bhp) & 250NM (184lbft)...

Having the 1.4lt means lighter nose weight...250NM still & 140PS...but its the torque which gets the car moving...& having 167bhp & 197lbft (267Nm) from an un-remapped 1.4lt ain't bad....& I reckon I can to better on the power & mpg....

June 2019

Got the extra Dynaudio badges fitted to the car in a way that I am 100% happy with & in such a way that its as if VW fitted them if the bean counters hadn't got in the way! I also did the usual guide:-

How to properly OEM+ retro-fit more Dynaudio badges to a MK7 Golf
https://www.golfmk7.com/forums/showthread.php?t=42734

So after spending the past couple of months with juddery front brakes I had a look....

Now I don't drive the car much, maybe twice a week, but it does 36miles minimum each time. This means that combined with my style of driving (a good driver uses gears & the brakes only get a quick dab) & the fact it sits in a garage the brake rust to buggery easy, especially in winter!!

Now I have always had this problem on other cars, & the front faces of these looked ok. So callipers off & look at the rear faces.....

Pad deposits, & rusty & uneven....WTF??...why so bad??

Also the lowest section of the bracket where the rear facing pad sits had a big build up of pad deposits which had filled in the gap between the bracket & the disc!!…& more rear pad wear!! The front facing pad had hardly any pad deposits left on the bracket!!

So loads of wire brushing, cleaning etc., striped sliders out, re-greased, & re-greased pad contact points etc.....re assembled everything went for test drive & way better...


Now the front faces are fine...just the rear faces, so either its the slider sticking or the pads sticking... Now I had previously greased all using the Mintex "Ceratec" brake grease....which was the stuff which failed on the turbo servo arm linkage, so is it duff grease??

I don't know, but this time I have used high temp clear lithium grease on the sliders, & the expensive Loctite grey 1300C grease (that I got for the sticking turbo servo arm) on the pad contact points. I usually use copper grease (with no problems) but want to try non metal grease.

The sliders appeared to be ok, & the pads maybe abit sticking, but not really "Stuck", so I will have to watch this space as they say!!

Another thing which has me thinking is the "splash shield".....which basically stops cold air hitting the bad face of the disc, so that back face has its own little micro climate....Yes I know the shield also protects the ball joint rubber boot from heat melt as its in the direct path....but as for water etc hitting the disc, well the front gets it also...& that's in way better condition.

I think because the splash shield creates this micro climate for the rear face it causes the pad dust to stick more as it actually traps more heat against the rear face...so might have to chop the top section off...or cut vent holes in it....


Anyway I think its more the grease failing & the pads sticking in place......

September 2018
Part 1

So after last month’s investigations into the brake judder what have I done this month??

How about a full service, remove all discs & pads, replace, overhaul, etc. the brakes front & rear...is that enough?? My physio likes me ATM as my back/arms etc. have gone on strike!!..

Front discs:-
After the last trial “re-grease” I was still getting brake judder so assumed the discs were really FUBAR & beyond recovery/skimming, so ordered some new pads & discs. Unfortunately the best OEM/road stuff is the previous ATE stuff which is getting harder to get here in the UK. I can order from Germany direct but the four main web sellers which are German with UK websites are playing silly buggers & not sending stuff out (without huge delays) to the UK (BREXIT & all that). So it’s a case of order what I can find here in UK. The market here is flooded with either Ferrodo, Tar.ox, EBC, or more track based stuff. This is useless up here & EBC I have had in the past. IMHO the quality has dropped & I have had failures. Plus I don’t like their assumption that all their discs need to be skimmed on the hub after “X” miles...& any problems you have with their discs are due to this not being done. NOT correct info & gets them “off the hook” for making a product to a lower spec!

After much research I ended up getting the Brembo “Max” grooved front discs (high carbon & coated), & their standard R90 road pads. I need a hand full of grooves to clean the pads of grit (too much up here & had problems previously)..so these discs looked fine. I noticed that the pads have the old metal shim/anti-squeal plate on the rear of the backing plate. The ATE ones had a fibreglass material shim (good for noise reduction) which had embedded itself into the various caliper/bracket contact points causing more friction! Not good!!! I also noticed that the guide pins had stuck AGAIN!! So the non petroleum grease (actually a high temp graphite/calcium grease) from the re-grease last month failed also! On closer inspection the rubber bush which is only on the top guide pin has absorbed/reacted against the grease & expanded..thus sticking this top guide pin in the bracket! AARRRGGGGHHHH!!!..

Due to the design of the sliding fist caliper, if the caliper sticks or the piston sticks, it is always the inside pad which will stick more. So you have to check the inside face of the disc, by removing the caliper & pads. You will then find, as I did, that the outside visible face is fine, but the inside face is FUBAR, with the inside pad worn down more than the outside one! So with the car up in the air I had to do allot of research & quickly! So I found a few posts on the drive2.rus forum on the subject of guide pin grease & TRW callipers. TRW make a specific grease for their callipers called PFG-110. Unfortunately I had to mail order it, but thankfully I found a sealed small sachet of the stuff left over from when I got the bigger calliper brackets. The TRW stuff is a special type of silicone grease, & does not react with the rubber used in the guide pin bush or the guide pin gaiters/boots.

So basically remove pads, disc, caliper, brackets. Undo caliper bleed nipple, connect drain hose & push piston back in with wind back tool & bleed off fluid into jar. Brass wire brushes & de-rust the hub & callipers. Use a worn fine metal file & clean out the pad ear channels on the bracket. Also smooth off the hub edge & the face with fine grade wet&dry sandpaper. Basically get everything de-rusted & smooth/flat, especially all contact/& slide areas. Also cleaned up the guide pins & the bracket to hub bolts.

I then reassembled using the new Brembo discs & pads. I also used the original rubber boots & bush from the factory guide pins I had previously saved, as these were like new & not affected by the wrong grease. I used the TRW grease on both the guide pins & bush, & then used Loctite LB8009 (in USA it is called “Heavy Duty”) on all pad backing plate to caliper/bracket contact/slide points.

So that was the fronts done & to a “better than factory” standard...

P.S. :- Below is a picture of the front ATE disc rear/inside face & pads, with the pads next to the new Brembo pads for comparison of thickness. Bear in mind that these were installed 23 months ago & have less than 10,000miles on them!!!..

September 2018
Part 2

Service Time!!
Since I purchased the car I have had the serviced done by the dealership , mainly to get the stamps in the book, & keep the warranty happy. Now I did pay for the 5yr warranty, but I got that primarily to cover the electronics going wrong, e.g. the satnav. So this service (4yrs) I decided to do myself, & it’s a big job as it’s an oil change, pollen filter, & spark plug change. The engine air filter I swapped earlier on this year for the ITG washable oiled foam, so it will just be an inspection on that as I have not done enough miles to warrant washing it!

Now my car, as all UK cars, are supplied on the VAG QI6 flexible service regime, which requires VW 540 00 specification oil, which is usually a 5W30 grade. I wanted to put it onto the QI4 fixed service regime which requires a VW 502 00 specification oil, which allows me use certain 0W40 grade oils! So I decided to also do an engine flush to make certain I was removing as much of the old 0W30 grade oil as possible!

So first job is to get the parts & any special tools that I don’t have. So I got some Castrol Edge Titanium FST 0W40 which is VW502 00 approved. I decided to try this oil as their name is on the oil filler cap, as in the past with other cars I always used Mobil 1 0W40. I got a Mann “FreciousPLus” cabin pollen filter as the Mahle 5 layer “Caremetix” filter I cannot get over here, anyway the Mann one is way better than the VW ones! The spark plugs I got were Bosch Platinum’s, as NGK don’t do an Iridium version yet & I had a hunch that the Bosch would be the factory ones after speaking to NGK who stated they get their info from Bosch on the design for these spark plugs! I also had to get the very expensive VAG grease “G 052 565 A1” which is to stop the ends of the pencil coil packs from sticking to the spark plugs. New specific tools like the coil pack remover, & special oil filter socket, (as the oil filters have to be tightened up to a specific torque setting) had to be purchased too.

I got the oil filter & new sump plug & washer from the dealers. Interestingly VW has moved back to the old way of reusing the sump plug & just fitting a new crush washer. However there is a procedure for the correct replacement. At the factory they fit the car with the previous style of sump plug with built in washer. At the first oil change they throw that away & fit a new sump plug which is a different length & has a disposable crush washer. So any oil changes after this first service, you just need to buy a new crush washer. More “Eco” as less metal is used, & cheaper..so why move away from that in the first place years ago?? Reason:- quicker to undo the sump plug/washer & let drop in drain can, & fit whole new sum plug/washer that’s why!! Idiots!!! Money & bean counters...remove the lot of them..logical engineering at its simplest is always best!!

Anyway the whole service went ok, basically drive car to get engine hot, park up, switch engine off, pour the Wynns engine flush in, idle engine for 20mins, switch off. I decided to remove the coil packs first whilst the engine was very hot as it makes the rubber soft. Even with the correct tool they were stiff, but no real struggle. I also loosened the spark plugs too. Then I drained the oil & lowered the car back down almost on top of the oil drain catch pan I have...& left it draining over lunch time. Come back after lunch, remove spark plugs, which were Bosch (as I thought), fitted the new ones, greased the ends of the coil packs & refitted etc.

I then jacked the car back up & removed the oil filter, poured new oil into the new oil filter to get it half full, & installed. The new socket/cup made the job very easy! Then fit new crush washer, car back on ground & then pour in 3lts of the new oil & wait for it to settle & read off dipstick & then pour in carefully the required amount. Now for my engine it states 4lts for a full oil change with oil filter...well I ended up pouring the whole 4lts in & even after running the engine it was still ¾ full up the dipstick! Thats the first time I have ever in 24yrs of car maintenance been able to fill the whole stated amount!! Usually it’s always slightly less as oil stays in deadspots in the engine & sump.

Anyway I did all the other service items, pollen filter, inspected the ITG engine filter, full electric function check of windows up & down, lights switches, headlights, indicators, horn, fitted new Bosch aero wiper blades front & rear, etc, etc.. Also did a VCDS scan, no fault codes except the usual intermittent short on MOST optical bus for the Dynaudio sound. Loose connector somewhere, will have to look at it but doesn’t affect the sound etc.!

Anyway I decided to remove the rear wheels to inspect the rear brakes & swap over to the winter alloys/tyres. Well good job I did as a total FUBAR of the pads/discs..!!!...

Anyway quick picture of the service items & tools...& will have to do a "How to guide" for the service/oil change for these small EA211 petrol engines...

September 2018
Part 3

Rear Brakes:-
I always knew my rear brakes were a bit rusty as they are way overpowered & most of the braking is done by the fronts anyway. I had got an “advisory” on my last MOT about them being rusty, so I decided to fully check them when I swapped onto the winter wheels before this years MOT. Good job I did as the inner pads were worn down to the minimum groove marks, so about 3mm of friction material left! As there are no grooved discs for the rears I just got plain replacement Brembo discs & their standard R90 road pads.

As I have the EPB you need VCDS (or OBD11) to retract the electric motor spindle, this allows you to push the pistons straight back in (you need to follow Rosstechs instructions exactly). I decided to jack the whole rear of the car, remove the wheels, callipers, discs, pads etc., then clean, de-rust etc. as per the front discs. I noticed that the pistons are the same as used on convention manual handbrakes as they have the indents for the piston wind back tool, which “screws” the piston back in. On these it’s just a straight push back in as they are not fixed to a screw spindle.

These EPB callipers have the old big stainless steel exposed slide pin with the 7mm hex/Allen key indent in the end. Due the way the caliper is mounted my standard hex keys/socket with a ratchet are way too long & will not fit between the trailing arm of the multilink suspension & the pin itself. So I had to remove the caliper bracket to hub carrier bolts first to remove the whole caliper off the disc to then get enough clearance to remove the slide pins! I did eventually get a very short 7mm hex/Allen key socket made for VAG applications with this “clearance” issue.

I got these:-
https://www.lasertools.co.uk/product/5584

As I had the ignition switched off I unplugged the ABS sensor connectors & the main EPB electrical connectors, purely to give me more movement of the caliper to get it out of the way & also improve inspection/cleaning etc..Although there is some clearance between the pad ears & the caliper brackets, it had rusted solid, & again the piston pad sticks & wears that pad down faster/more. VW do not grease the pad/bracket contact points at the factory, or state anything in their workshop manuals! I had a real job getting the discs of the hub at first, however I found shorter way! Get to the rear face of the hub (via the space where the caliper sits), & the edge of the hub is what rusts to the inside of the brake disc bell. So spray penetrating fluid in (I use “Plus gas”) & rotate the disc, so it gets the whole way around. Then hammer it off using a rubber/plastic mallet/hammer.

Again clean, de-rust & grease everything up, using Loctite LB8009 (in USA it is called “Heavy Duty”) on all pad backing plate to caliper/bracket contact/slide points. I used wet/dry sandpaper at 2000grit to clean the slide pins, & then the internal grooves of the rubber bushes I filled with the TRW PFG-110 grease as it will stay in there & act as a reservoir for the slide pins. Then refit everything noting what I had done to the fronts also. So everything fitted back & grease up, & way better than factory! Again use VCDS to activate the EPB etc.

I took the car down the same road & did the same braking etc as I had done to the fronts, to bed the rears in. What a difference in the handling, the car was over steering like mad!! Basically the rear brakes were operating better than when they left the factory, so the stability & traction systems could work better, but it was too aggressive for my liking, i.e. too artificial, & the car was basically turning in on itself far too easily! So get home, & plug in VCDS, & yes it was set to “Strong”, as I had previously turned it up from the factory setting of normal as it was doing nothing (because of the extra friction of the pads sticking). So I set it to “Weak” & I hardly felt anything from the systems, & the car was no under steering, a bit too much for taste!. So set to “Normal” & although better, it was a bit too strong for me. Finally I set it to “Medium” not knowing if this was stronger or weaker than “Normal”. That is perfect for me & is weaker than “Normal”, but stronger than “Weak”.

Anyway below is a picture of the pads from the rear..as you can see totally FUBAR...after 4yrs & I have not touched these at all, so as per the factory!

October 2018
Part 1

So after the full service, overhauled brake system including new discs & pads, what else to do?? How about a full clean (now that the brakes have been bedded in), & swap the summers back onto the winters. Also fit a set of Melye HD (Heavy Duty) front ARB drop links.

Meyle are a German OEM manufacture of car/truck parts, who do a “HD” range also. When they notice repeated failures of the stock OEM parts they make, e.g. they sell more, they test them & find ways to make it stronger & last longer & then include a 4yr warranty on the product. So far on the MK7 Golf it’s just the front drop links & the main rear arm big bush. On the drop links the ball joints are bigger in diameter, so more surface area for the load to be spread over & thus less pressure per mm of area. They also have a 16mm spanner fitment on the joint, so you get a 166mm spanner on one side to lock the ball joint whilst you tighten the nut! VW you get a 12point TX start type in the end of the spindle, which usually deforms...way to go VAG!!
I’ll have to do a brief “how to guide” ..again..

Anyway so a full clean inside & out & the G-techniq crystal black serum ceramic coat is holding up well for almost 4yrs of age! Spent ages cleaning the inside & outside of the class to 100% smear free from every angle! Vacuumed the inside also, & wiped all internal surfaces down with cleaner, then warm water & dried etc. Also applied rubber/trim stuff to all the door rubber seals, & window seals. Again all G-techniq stuff used in cleaning etc the car as I have since I got the coating done 4yrs ago!

Decided to take some pictures..loads in fact, will post up later

October 2018
Part 2

So having done all the mechanical work & cleaning to the car, resulting it in being in “tip top” condition, & “better than showroom/factory” (take your pick) it was time to take it to the dealers from its annual MOT! AGAIN?...Yep its 4yrs old now (purchased new 31/10/14)!! How time flies when you’re having fun!!

I also decided to get the dealers to carry out the brake fluid change, & yes I could have done it whilst I overhauled the brakes, but its easier & quicker for them to do it. The dealers also stated that there was a new recall for my car which was the “46G7” update for the EPB. Now I first heard about this in May last year (2017), & expected to have it done at its previous MOT/service in October last year, but was told then that there was nothing! The dealers stated VWUK issue them with the recall notices “as & when”, & knowing VWUK I totally understand!! Anyway this recall only affects the 2WD manual gearbox versions which have the EPB (electronic parking brake/handbrake), & is basically a manufacture applied software update, & not a Government listed “car is faulty” recall!

I also got VWUK to confirm in writing via email that their “69U6” recall (replace passenger airbag ignitor, as faulty) is not required for my car! I had noticed this listed on the UK Government recall list for my type of car, within a set chassis number range & build date range, my car falling right in the middle of these ranges. However what was strange is that it stated only 21 cars of my type were affected, but the build date & chassis ranges covered about 20,000cars of my type!!

The car passed the MOT with flying colours...as expected! The bonus being that the emissions are half of what they were last year, which means the engines run in properly & it likes the new 0W40 grade oil!.

The emissions results:-
Fast idle test (2500-3000rpm)
CO = 0.00% (0.20% Max. allowed)
HC = 7ppm (200ppm Max. allowed) (was 13ppm last year)
Lambda = 1.00 (0.97 - 1.03 allowed)

Natural idle test (450 - 1500rpm)
CO = 0.00% (0.30% Max. allowed)

I used my VCDS to do a full “admap” & “auto scan” of the car before I sent it in to the dealers for this 46G7 update, so I had a “before” copy! I also used it to reactivate the stop/start for the MOT & then to deactivate it when I got the car back. (I hate that feature soo much!!!) When I was checking what the dealers had done for the 46G7 update I noticed that the long coding in the ABS module had changed, so I posted a question in an existing thread on this forum about it as my brain wasn’t working. Turns out its the popular ESC coding, as my car just had “02” = ESC & ASR ON / ASR OFF / Blank, & I had previously altered it to the GTI/R “09” = ESC & ASR ON / ASR OFF / ESC SPORT. So when the dealers did the software update they (or the software) altered this item which is not from factory on my trim spec, but left all the other coding & adaptations in this module which were altered from factory! Very strange!! Anyway altered back to “09”...

October 2018
Part 3

I was doing some Google fu (dangerous I know) & stumbled upon a few modifications, that I could do to the car using OEM parts!
The first one is to replace the corrugated EVAP hose with a new smooth bore rubber hose. The old part caused noise which I have heard & just thought “its the engine doing its thing”. VW have not issued a recall or changed the part number, so are “hiding” the fact they ballsed up the original design!

So Ill have to do a how to guide!!

The other part is the new design coolant expansion tank cap. The old ones are a real PITA to undo when the system is hot/warm. Anyway I ordered the part & it fitted too easy, so I measured it & its about 0.5mm smaller around the “O” ring section. Anyway I have driven the car with it hot & had no pressure loss, no leakage, & it takes a good full turn & a bit before you hear any pressure release. I recon as the previous one was such a PITA & would get stuck they redesigned it & made it slightly smaller in diameter.

Again I’ll do a quick guide with the part numbers..