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Discussion Starter #1
HAving some problems with loss of power, going back home yesterday and I decided to go into full throttle suddenly my rpm was at 4000 and there no more power had to get my foot of the pedal then and there it could go above 4 any ideas of what that my be. But if I kept my foot down it studdered.
 
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Discussion Starter #2
yann you have a Q4..??


it sounds like it could be a vacume pipe split or something similar......
steve webb maybe able to offer you more help.
 
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Discussion Starter #3
Wheres that piece located and what is it?

And its a Q4
 

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Yann

The same thing happened with me a couple of months ago.The ECU cuts the power,probably it's sensing your boost is too high.There is an overboost valve(little alluminum thing with a black vacuumhose on top) sitting on the radiator side,close to the left headlight.There are 2 vacuumhoses attached to this valve(bottom side).One is coming from the wastegate,the other from the turbohouse itself.If one of them came of,or became split this can cause a too high boost situation.If everything looks allright,maybe the overboost valve is faulty.There are two wires attached to the valve(bootom side,right next to those vacuum hoses).Deattach these wires,and your when you floor the car your boostreading should be 0.6 bar(baseboost).
Hope this helps!

ps:Sorry for my english mates!
 
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Discussion Starter #5
Your English is very good M80....don't worry. Even I understood that and I don't own a Q4 :)
 
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Discussion Starter #6
Thanks I'll check it out today, i'll keep you posted.
 
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Discussion Starter #7
I checked out the wires they seem ok. Now since that is working fine what should I change.
 
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Discussion Starter #8
Was it popping and spitting and generally running like a dog?

The problem is that when you split a small bore pipe, especially near the APS (absolute pressure sensor) the ecu thinks that the car is not producing any boost, but infact it is. So the ecu leans the engine out hugely. Not difficult to fix, but just don't use it till you fix it, running that lean could cause you to melt something , probably a piston.

I've had this happen to me twice now, first time on track, car suddenly wouldn't pull, and running very rough, turns out the small bore pipe going to the APS on the bulkhead had come adrift. 30 second fix.
The next time, a pipe had split where two small bore pipes are joined with a copper insert, pulled off the split part and stuck the two pipes back together, hey presto, fixed.

Get yourself a torch and hunt around for that split pipe.

Steve
 
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Discussion Starter #9
Did everything you guys told me to and there still seems to be a problem with my cars power. Any other ideas of what it might be.
 
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Discussion Starter #10
Right the next thing is plugs, is your car moddified or is it standard? How long ago did you change your spark plugs?

When I had my turbo upgraded, at somewhere around 3750/4000 rpm the turbo was building boost pressure at such a high speed that it was effectively blowing out the spark plugs. Full throttle in 3rd would cause the car to stutter, once the plugs were changed to harder/colder plugs the problem pretty much went away. And i'm not running silly amounts of boost, just 1.35 bar.

Steve
 
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Discussion Starter #11
Just found out today that the wire which gives the electronic data to the baseboost is cut open and now i cant see at what level my bar is. wiht the spark plugs I changed those like a month ago.
 
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Discussion Starter #12
The car is standard havent done anything yet to the motor.
 
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Discussion Starter #16
Its still a standard one, seems to be able to cope, or has been for the past 20k miles, think it might be on its way out soon though. I don't indulge in the traffic light GP so the clutch gets a fairly easy life.

Steve
 
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