Help! Power Loss

[gbhdavies]

I hope someone out there can help me.
My car is an APR chipped S3 and isn't running correctly. Sometimes its fine, and then sometimes it runs like it hasn't got a turbo fitted. Someone has suggested that this may be my N75 valve? Can anybody offer any advice as to what they think it might be. Any suggestions readily accepted.
Cheers
GBH

 

[nervus]

It could be a leaky hose somewhere. There is a Y piece hose which notoriously breaks in the v of the y (make sense). It taps off boost to the brakes i think! Check all your hoses for leaks, its sometimes tricky to spot.

It could be the boost actuator sticking (happened to me with 8k miles! Lets hope not unless under warranty as the actuator is part of the turbo housing and thus a new or recon turbo needed

Could also be the diverter valve leaking, its a common problem. I would expect power to be permanently down though not intermitant. maybe its sticking

Its easy to check, remove it (two jubelee clips and a pinch clip).

Push the diaphragm spring up the chamber with your finger then place the palm of your hand over the side outlet of the valve. If the diaphragm piston stays at the top its okay, if it returns to the bottom its leaking!

Thats all i can suggest but there are some real experts on here who will know more PM Ess_three he is the resident wizzard!
Hope this helps!

 

[RichA3Turbo]

When you say its like there is no turbo, does it actually spool up at all? If not, then check the wires onto the N75! Ive seen before when one of the wires in the plug has snapped which gives you ZERO boost. Worth checking out. Have you got VAG-COM? are there any fault codeS?

Rich

 

[gbhdavies]

Don't have a VAG-COM Im afraid. I first noticed a problem on the motorway when power seemed to drop right off at about 4000RPM. Then it semed to be fine again. This morning, it was only running like a 1.8i or something and was then fine again. Does anyone know anywhere I can get it plugged in? My local stealer is busy for 3 weeks.
Cheers for the help
GBH

 

[gbhdavies]

ps I,m in Birmingham at the moment. Can get away from work if necessary.
Cheers
GBH

 

[benk]

I thought that loss of power at 4000rpm was often said to be a MAF problem..

 

[gbhdavies]

The 4000 RPM was an example but this problem just seems to manifest itself and then disappear. Thanks for the advice re: the MAF sensor, but I had a new one 12 months ago and have done less than 5000 miles since then. I appreciate it could be this but it doesn't feel the same as it did last time. I also have an aftermarket RC valve so hope it isn't this. I need a plug in, but I'm cluthing at straws before I book it in. Ess_Three are you out there?
Cheers everyone
GBH

 

[gbhdavies]

Bigvern, you may well be my saviour!
Only this weekend have I fitted new Samco intercooler hoses. And the problems started tuesday. Could be that the intercooler hoses haven't been fitted correctly. I'm a bit thick with the technical stuff, why would the intercooler hoses cause power loss and can anyone offer advice on ensuring they are fitted properly?
Cheers
GBH
They better not be split, they're brand new Samco ones!

 

[bigvern]

might be losing boost pressure then going into limp mode i think thats what happened to mine but I'm not clued up either
vern