Power loss-please help!!!

[jonesey1964]

hi, i've got a 1999 tt quottro(225) and am having problems due to a power loss. I put a boost gauge on it and ever since then it's lost a lot of power! This may just be coincidental because we've gone through and checked for air leaks in hoses and checked for cracks in the diverter valve and there is still a big loss. The vacuum is very strong at idle and i don't think it's a vacuum leek. It's running very low boost. The only visible split is on a breather hose that comes out of the rocker cover into the induction system.Could this be affecting the performance? Or can you suggest anything else that might be the problem?

The MIL(engine) light is not illuminating when the ignition is switched on. Maybe the previous owner had something to hide!
Thanks a lot, help is much appreciated!

Martyn Jones
(jonesey1964@yahoo.co.uk)
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[Wak-VAGCHECK]

where are you based?

 

[jonesey1964]

nuneaton near coventry. Think you can help? It's been on a diagnostic and it's kicking out the code 17697 and 17955 which is pointing at the turbo wastegate solenoid. However i've changed this sensor and it's still coming up with the same code. I've been advised that it's an electrical problem with this sensor! Money out!!! Please help
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[Wak-VAGCHECK]

do both faults return? the first error relates to the N249, which is a valve that can open the DV if needed

the second error is related to the turbo wastgate controller N75.

which valve have you changed? If its the N75 Its worth pulling the battery -ve terminal for 5 mins
reconnect
ignition on, dont start
wait 20 s
iginition off then start


if its both faults then it would imply a wiring issue but some data logging may help isolate the problem.

 

[jonesey1964]

Thanks mate. Both codes do return yes.
I changed the N75 valve(wastegate regulator), reset the battery but didn't do the thing you said about waiting and turning the ignition back off then nack on again. Would this make a difference?
I've spoke to my local audi specialist(not the dealer)and he suggested it may also be an electrical issue too.
Do you know how tricky/expensive this could be???
Thanks for your help!
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[Wak-VAGCHECK]

its hard to say, coil pack wiring looms are known to get brittle and short, the N249 follows the same path and perhaps there is a chance something is there.
It needs some attempt at diagnosis, reviewing wiring diagrams and checking continuity as well as each component. it could be found in 1 hour or a few more than that.

Need to find a local specialist as we are too far.

The ignition on and waiting is a throttle body reset, its adviseable to do this after a battery disconnect making sure no pedals are touched.

 

[mark hobbs]

whats the car doing when u driving it mate , does it feel like its holding back and not letting the power through on the turbo. if so ive just had the same problem i was told its the air mass meter ive brought a new one fitted it and now she is running sweet and i can here the turbo working fine now its a common fault with all vw audi cars try it ........ costa around 50 to 70 pounds for a new one or try ebay u may get a new one for a bargain............ mark hoobs