unsolvable engine problem

[timucin]

yep its me and my car again;
2-3 weeks ago suddenly car lost hp.
the fault is :
-it drops the boost to 6 psi at 5000rpm in all gears except first.
-it drops the boost to 6 psi on fast up-shifting.i mean if i pull to second and leave the clutch immedately it stalls,keep the pressure at 6psi for a while but after it boost normal until 5000 then cuts again.but if i change the gears 'grandma style'then it doesnt stall and work ok untill 5000rpm.

things i had done to untill now:
1-changed n75
2-changed bypass valve,(under n75)
3-changed air filter
4-cleaned maf
5-did hundereds of hose leak test result:everything is ok
6-no fault code on computer
7-controlled intercooler and in-outs hundred times
8-controlled all hoses ,i mean all not just turbo releated

but it still does the same thing.i knoe the best way is to hit the car to a tree and ask insurance to pay but does any body have any other idea about 'how can i turn this car back to normal?'
thnx for help

[Greg_S]

might be worth trying a different ECU if can get one to try

[lskov]

I had a simular problem recently... Have You checked the magnetic valve for regulating the turbo pressure? Only a wild guess, but it worked for me...

[timucin]

i dont have any chance to try another ecu;
Iskov can you pls give me more detailed info about that part,part number ,where is it located,how does it look etc?

thnx

[jubjub]

I had a simular problem recently... Have You checked the magnetic valve for regulating the turbo pressure? Only a wild guess, but it worked for me...

Is this the wastegate freqeuncy valve?If it is, its down behind the drivers side headlamp, is quite small and has three little hoses going to it.Apparently it should click or if you touch it you should hear/feel it clicking when you rev the engine.

[Greg_S]

thats the N75 valve. I think timucin already done that one

[timucin]

yep i changed that;

[NIKOLAS]

Hi
Timusin as i have already told you i had similar problems. I just found the problem three day ago when i went to install the H&R suspension i received fro germany. In the meanwhile i had changed N75, blowoff valve, westgate membrane etc. Well the problem is my exhaust manifold which has a very small crack which makes minimum noise. But as it heats up it loses all the pressure from there so there is not enough power to spool up the turbo. By the way i have ordered a new exhaust manifold as well as KKK26/27/29 turbo and the programmed chips for it, as well as a turbo-back SUpersprint exhaust system with no cats.I will let you know of the results.hopefully i will have the parts send by the end of next week so i should have them installed by 10 to 12 of February.
Then i ll need better brakes and so on... Nick

[timucin]

things i had done to untill now:

1-changed n75

2-changed bypass valve,(under n75)

3-changed air filter

4-cleaned maf

5-did hundereds of hose leak test result:everything is ok

6-no fault code on computer

7-controlled intercooler and in-outs hundred times

8-controlled all hoses ,i mean all not just turbo releated

9-changed spark plugs

10-controlled all wires releated to sparks

11-removed cleaned ane reinstalled rpm sensors

12-removed lambda nothing changed,sprayed,dried and re instaleed

13-removed battery terminals on each step to clear ecu

14-rechecked breather

car is still cutting at 5000 and stalling on fast shifting

i didnt check exhaust sytem will do that tomorrow, but i have incredible amount of boost until 5000rpm.20-25 psi?!?!?

[PP]

It may be I have the same problem on my RS2 - my car drives like a normally aspirated car (no huge kick) - is that what you are experiencing?

[robo]

I think i got that problem too.
6 months ago i removed exhaust manifold and i did see 2 or 3 small hair line cracks , it could be it.
The car dont realy wana go ,like the car got hickups.
Nickmac where did you get the manifold from (webby) which one is it and how much? I know i can get one from vag for about £500, but that must be standard one.

[timucin]

Pradip;
not exactly.. i feel the kick its ok but at 5000rpm turbo press drops to 6 psi from 20psi.not at 4950 0o 5050 rpm exactly at 5000rpm.if i drive the car under 5000 rpm and shift-up slowly there is no problem.if i shift up sporty it stalls for a while like 5 seconds and then boost comes back and it moves as it should...

will check the exhaust tomorrow and post the results here

[timucin]

there supposed to be a sensor in front of engine block,somewhere close to trigger belts.what is the name of that part?what is the part number?does anybody have pic of that?thnx for help

[NIKOLAS]

Yes my car was running almost like a non turbo the last few days. Anyawy i have ordered a new exhaust manifold fro www.totsteile.com or email [email]tots@bluewin.ch.[/email] it, s around 700 euros. Thats the RS2 oem part. If you want something better you can get the sport quattro manifold which is nearly double that price. Anyway i preffered buying the oem manifold and spending the change on the KKK26/27/29 turbo ( at 1650 euros. Although i know i will be needing the sport quattro ex.man latter on....
I have just send the money through w.u. so i am hopping to get the parts by the end of next week so i will post the results in ten days hopefully. Iam also getting a new supersprint turbo back no cats exhaust and the BMC cda-09 filter so i will let you know of the impressions of this combination.So far i have spent 25000 euros ( resprayed, leather, hi-end ice, soundproof material at the door panels, lots of details from Raid geargnob to Raid steering wheel, and from new hoses to water injection)plus the 30000 i bought the car and i will probably spent some more( eg brakes, set of clutch, alloys)and the car is still not going as i want it to or as it should be. I have been trying to bring it to as new condition, and i hope i wont [img]images/graemlins/062802beat_prv.gif[/img] at the end.
Anyway it's all about acceleration...

[NIKOLAS]

Also timusin since you have tried so many things try this one to: Before my problem with the exhaust manifold i was facing similar problems with you when i was using low octane fuel.( due to detonation - knocking that triggers the knock sensors and the ecu cuts the boost). Whe n i used the BP 100 octane i had no problems or when i used the Cyclo "Octane boost" ( www.cyclo.com) ( at 12euros per bottle per tank) with other 95 octane fuel. Have you tried this? Because i suppose that as here in Greece the fuel in Turkey has nothing to do with the quality found lets say in u.k And i know that in fact since when i was studying there (KEnt) i used to own a 735(BMW) and later on a M5 and they had a significant and very noticable reduction in output when in Greece and that was mainly due to the fuel.(and other reasons but mainly the fuel). Hope we make these cars work at the end....