B5 1.8T

Arrkon

Arrkon

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Hey all, had a bit of time away whilst running around in a 1.8 mondeo :mad: but now upgraded to a V plate 1.8T A4. only experience ive had with a4's is my old avant TDi. no real problems other than the typical impeller implosion and a little metallic rattle/whine when "coasting" in gear.

Thus my questions are:
  • What could this whine/rattle be?
  • any things to look out for on the APU engine?
  • why wont the alarm sound but the indicatiors flash? just the sounder in the boot???

All advice/input welcome :arco:
 
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The metallic whine/rattle might be the wastegate back plate on it's way out mine is same and needs new turbo and Aragon has had this with his, get a bar or extension and place it on the hot side of the turbo and place your ear to the bar rev it up and you should here it clear as day when the revs drop back to idle, hope it's not mate but you will probably find it is but least you get a new turbo ie bigger or a k04 :)
 
Incase it is, What cars have the K04 fitted? (ie so i can find a second hand one) and whats involved in the change (IC, manifold etc...)? or is it just a straight swap....
 
Erm not to sure which have it fitted maybe b6 a4 or passat 1.8t's but you can only use one off of them not a s3 or tt as our engines are longitudinal the others are transverse I no the k04-015 is straight bolt on just slightly bigger than k03-029 which I think is on yours and mine just may need to mod intake as inducer is larger by about 8mm I think have message a few sellers on flea bay and some have said it's same size as the k03 inducer and some have said you have to mod so would be worth having a good look into it.
 
Cheers bradderz, will get my steth on it tomorrow... do the backplates detach or just rattle progressively more? may see if theres some way to fix it rather than replace... the time for modding fun will come soon :yahoo:
 
I would say rattle progressively more then eventually detach you should be able to get it repaired of a specialist they sell the backplate on eBay just need to no measurements of the plate when ordering if you search 'kkk backplate' you should find it. Just curious what's the milage of the 1.8T ?? As mines on 121,700 and has been rattling since around 118,000 but has got worse it even rattles when I switch the engine off as last bit of exhaust gas passes it. Does my head in I'm constantly having to put my foot slightly on the gas to close the wastegate so I can't hear it lol
 
Mines on 130k, but have a reciept for a huge rebuild a couple of years back costing £1700:faint: would this be the part you were on about? KKK Backplate

Would any benefit come from fitting a BOV/forge WG?
 
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Ye looks similar to that but that's the wrong part, I don't think you will benefit from fitting either as it's the plate on the flapper that rattles and is in the turbo the forge wastegate is just a uprated actuator for when you are running high levels of boost and is adjustable iirc. So your best route is either as I said repairing your unit or getting a new turbo, at 130k I'd be looking at getting a new turbo I will be purchasing mine at end of month and I'll get sum pics up of it, it might be worth getting your old turbo repaired if you get a new one and flog it on eBay for £100 least you get something back off it !
 
Nothing came with a K04 as standard. It was sold by Borg Warner direct as an upgrade option for our engines.

One possible option would be to find a blown-up k03 that has a good housing and swap it over. I've done this with a spare k03 i have (the one that spat its wastegate on my old car)
 
Cheers guys. Just realised another problem... The car is hesitiating really badly. would the WG backplate cause that? VagCom'd it, only dtc was 17931 (crash signal inplausable), but this shouldnt cause rough running??? it runs fine up to 2.5k and hesitates after, even when sat still, so its not under load...

Any suggestions before i spend my time chasing vac leaks and the like?
 
May have Sussed it, think the air mass meter is playing up, cleaned with brake cleaner and it was ok for a little bit, will replace the AMM me thinks...
 
Final thought of the day... Is the K03 fitted to the APU engine (ie: mine) also fitted to other 1800T lumps? (AGU maybe?)
 
i had a dodgy recirc valve that caused horrible hesitation like you describe, especially low revs coming on and off the throttle.

your alarm doesnt flash when locking as it has been coded to do that in VAGcom. someone more up to speed with that should be along to tell you how to change it. mines the opposite, flash no honk
 
JCB, i think you misunderstood (probably my description) the alarm arms/lights flash, but if i set the alarm off (by opening door or moving inside, the lights flash but no horn/alarm sound... suspect the backup sounder has gone U/S.

As previous post, I have fitted a new AMM/MAF, and all is good :D very happy with the performance (for now:whistle2:)
 
Rconn said:
Final thought of the day... Is the K03 fitted to the APU engine (ie: mine) also fitted to other 1800T lumps? (AGU maybe?)
Click to expand...

APU has a k03-029, which is only used on longitudinal A4 1.8T's. Most B6 1.8T's have the same turbo.

Golf/A3 turbos wont fit.
 
cheers aragon, could i not thrape an A3/Golf (AGU) turbo for the parts to fix mine?
 
I'm curious about the alarm issue to as I had my windows down at work the other day and someone triggered my alarm and again only indicators flashed with no noise, is the button on the B pillar trim anything to do with this or is just to turn of the ultrasonics ??
 
The siern on ours was broken when we baught the car. I replaced it, and turned on the locking chirp so i know its working every time i lock the car.
 
Mine was U/S, pulled it apart last night to find the board covered in green fluffy corrosion. think a replacement is in order...

As for location, on the B5 its in the drivers rear quarter, next to the CL pump.
 
If you have vagcom just scan the central locking controller for faults. No doubt you'll have "Alarm Horn, No Communication".

The battery leaks acid all over the PCB and it corrodes away.

I got a replacement from a (iirc) '06 A8 from German Ebay, was around 30-40quid
 
To replace my turbo, ive been looking around on various forums, what turbos are direct bolt-for-bolt replacements? i know i could get another K03-29, or a k04-XX (what number?) but is the K03s a swap or is there more involved?

Advice?
 
The only other standard turbos that will fit your car are the K03-073, which was only fitted to 190hp B6 1.8T's, and is an equivalent to the K03s fitted to the later A3's, and the K04-015 which is the turbo that borg-warner sell as an upgrade for our engines, and is more or less the same size as the aforementioned -073 turbo. Both of these are capable of around 230hp, with the k04 perhaps managing 240 with the right bolt ons.

After that your into something like the ATP eliminator series which are garret turbos that have been modified with a custom housing so that they bolt streight on to your existing manifold/cat etc

edit: i had k04-001 when it should have been 015.
 
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Will a k04-015 bolt on show any gain in hp as I've been looking at these and have seen they say upgrade to 210hp is this a blag or is this genuine as I'm looking at getting the xs power k04-015 unit ??
 
i wouldnt touch an "XS Power" turbo with a barge pole unless you want to be changing it again in a few thousand miles.

It will bolt on, and is good for 230-240ish with a proper map.
 
I'm looking at getting a bolt on scroll unit as I've just read lee's 'turbo upgrade' post and looks interesting and think it would be better going down the hybrid route. And he seems happy with his just waying up the sp51x and sp54x but I don't no which route is best ??
 
SP51 doesnt exist any more, they're all sp54's afaik.

He does a few different ones though depending on what its based on. Realistically though, if you go for a scroll, dont expect more than 240hp, unless you go for one of the larger units like the 56 or 60.

As i've said before, i dont think a turbo swap is worth it unless you're getting 100hp more out of the deal, but i can see the appeal of them if your not really wanting to tune the car, and your needing a turbo anyway because your old ones broken, as they cost more or less the same as a rebuilt standard turbo.
 
Going to go with the scroll k03-sp54x Sean at scroll has just got back to me and for turbo and postage it's just short of £600 and I would be happy with that as I'm not looking for Hugh horsepower gains 240hp will be enough for me for the time being !!
 
Rconn said:
May have Sussed it, think the air mass meter is playing up, cleaned with brake cleaner and it was ok for a little bit, will replace the AMM me thinks...
Click to expand...
Just check the wiring to the MAF as mine had a loose wire on the plug. VAG -Tech diagnosed and sorted this for me as I had been pulling my hair out trying to suss it out
 
Yep that's the puppy, due to my cat falling of put my fingers in and its loose as he'll lol
 
cheers fella. may have a look at some point, drop the exhaust/cat and see if i can do a fix like the bimmers. as it seems they have a similar issue :D
 
I'm going to get it fixed after the new k03 hybrid turbo is on and try flog it on the bay and see what I get for it I be happy with £100 or am I being greedy lol
 
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