rbertnitro

Good evening everyone. Ive decided that my rear calipers are needing a refresh as they are sticking. Purchased a rebuild kit with all seals and pistons, Everything looks good except the pistons. The inside of the piston is a smooth bore and then goes down to a smaller diameter at bottom i was expecting to see some sort of central pole with threads that screws on to the handbrake adjuster screw in the caliper. Cant find pics of vrs ones online but every golf and tt or a3 ones i have seen have had a female thread part in there. Can anyone help are these the correct pistons or is there a part that needs transfered from inside the stock pistons? Id like to find out the deal before i remove the old ones. Cheers for any advice

Funny you say as i have had 17705 (pressure loss between turbo and tb if i remember) but its only been a couple of times, nothing specific apart from its only showing up when im using the mbc as a bandaid to acheive at least stock boost.another curious thing is my sai pump doesnt run at all now but i never get any sai incorrect flow faults.

Im using the std vrs one i also have a year old 007p and theres not much difference between the 2 when fitted.

I made myself a little diy pressure testing setup with a small compressor to check for leaks none found.i do still have a pssssst sound when im under heavy load from left side but im at a loss where its from as no leaks and holds boost with a manual valve.

Hi ive run into a strange problem with boosting on my auq it appears to not like n75 valves.it started doing only 5psi a couple months ago from cold but since it only happened a couple times i wasnt concerned since then i had a stage 1 map on it and now wont achieve over spring pressure at all. Ive checked it can achieve boost using a cheap mbc and im using that as a bandaid at 10psi while i sort this out. Tried several n75s all f type valves a couple out of used but previously proper boosting auqs and a brand new one albeit a non oem copy valve. Result was none of them produced more than limp pressures done a check on vagcom and sure enough with the new stage 1 map its requesting 2085mbar which i think equates to around 16psi or so, i also checked the n75 dc in vagcom and the numbers seem to be ramping up to high 90s.im not sure of any other way to go about testing n75s. Also after the map i constantly get a 17704 cooling system fault even after changing cts and stat for oem items i get this code right away at startup and it only allows me to clear after 10mins of running.on vagcom temp reports fine holding at between 85-90 constant.then the next day there it is again code pops up right on power up. I know my turbo is producing boost ok as the manual valve allows me to set boost as i please but i dont want to run with this forever as its got bad drivability also i done a diy pump test for boost leaks and none apparent (i replaced a lot of pvc stuff last year along with coils and plugs) actual boost also seems to be reporting identical to guage in vagcom and maf readings as far a max goes seem in line at 142gs when i use 10psi.i would have expected some response even if its surging from the valves ive tried but its just constant 5psi from them all. Any help and guidence would be great if anyone knows whats going on here thanks

is there any sort of guide to testing the mafs values with a multimeter id like to be more sure.

my idle wasnt the problem originaly.it was only when i initialy unplugged the maf that idle was rough.when the maf is plugged in and its surging and limping it idles great infact it drives perfectly in the vacuum to 0psi range.only when boost starts to come it goes nuts. now when i unplug my maf a second time it idles great and drives thru the whole range inc boost perfect just slower.i think i may need to rig up some kind off pressure tester using a bike pump or small compressor to check for further leaks cause theres not much to see just by eyeballing it tbh

before.when i unplugged it to test it started and idled rough drove alright but still did its strange boost all over the place thing,it calmed down a bit once i got to work that day but still unsettled at idle.havent drove it at all most of weekend.then when i have the plug off again its smooth and better psi is only peaking at 8 or so,lower power but no mad spiking and surging like before.i can only assume its possibly adapted a little to having the maf unplugged. it still goes ape when i plug it in tho. didnt do anything else apart from a scan with torque android app and the blutooth dongle

so im waiting for my vcds cable to arrive.decided this weekend to clean the maf see what that done since its free.anyway cleaned it as best i could with a can of maf cleaner then put it back in.however forgot to connect the plug took it for a run and now it actualy runs better with the maf unplugged.im puzzled as before it ran crap with it unplugged.post clean its still **** with it plugged in but now whenever its unplugged it running better and smoother albeit with reduced power and midrange.im more and more thinking of just ordering a maf even though i havent vagcom logged it yet.anyone chime in with thoughts?

oh well worth a try.i may order one anyway as going by the vag cars ive had in past im no stranger to having to fit new coolant sensors to them

yeah thats my next port of call as i believe vagcom is better at finding all the codes than these generic obd scanners.in fact at only 99dollars (65pound near enuf) for the full registration of the older version i may just get it myself. Could be worth a shot but is it possible that the coolant temp sensor from my mk3 vr6 is the same and would fit this engine? ive got loads of spares laying around for the vr6 and if anything is compatible between the two i could shove it in right away as my mk3 has the engine out just now so not needing them immediately

quick update.tried unplugging maf this morning on way to work= inconclusive. only a 3mile drive but id say it ran a little worse with it off.struggled to start initialy and idle was all over the place not as much punch performance wise and just seemed generaly worse.i did notice the boost was slightly lower but it was still doing its odd ramping up way high,hesitating and then dropping like a rock down to about 3psi. with the maf in it accelerates and boosts fine if im carefull with the throttle and gentle with it going on smooth and slow.but a slight 1mm more pedal on high gear high load (hills) situatuons and its whooshing like a leaf blower and going nowwhere.boost spikes up then throws a wobbly and plummets to 3 or 4psi. closer inspection earlier i did notice i had a small split in a oil breather,its the one that comes off the y camcover piece and goes down i to the block its split just before it goes into the connection lower in the block. would this split cause such crazy running and boost probs i thought these breathers didnt see boost in them?gona get it temp fixed up for now while i order the replacement. and find someone to vagcom my car

right thanks.il have to find someone local with a copy of vagcom then.eliminate the tb at least

right i will certainly try the maf off anyway.only other things i could think of were it might need a throttle alignment as the battery was off for some time while i was fixing door control module wires.also when is boost supposed to start as i can be light on throttle and itl be in vacumm or 0psi rite up to high revs and a decent speed its only when i take a chunk of pedal like 1/2 throttle or more the psi starts to climb above 0

thanks yellowcar no ive not tried mafless i will give it a try in the morning.yes thats right up to about 10psi on my gauge altho id assume it would have a bit of an error margin as its a £10 gauge.not been mapped that i know of prev owner didnt say.i got the gauge after all this started but when i got it was very quick quite a bit faster under 100 than my mk3 vr6 so could have been mapped and now its running crap but i doubt it as its refusing to go over 10psi. would unpluggi g coolant sensor prove anything?