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Author Topic: Strange intermitent boost problem - please help :)  (Read 2135 times)

Offline RENNTAG

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Strange intermitent boost problem - please help :)
« on: November 20, 2012, 04:44:30 pm »
Hello,

Hopping someone may have an idea of what could be causing this problem. First some background.
The car has a stage 2 AMD map and a Blueflame 200cel TBE. It is DSG KO3 GTI
I went to the recent JKM rolling road day and the car only made 234BHP (There were some stage 1 cars making more power than me)
The printout from the Dyno showed my air fuel ratio to be very rich. After the session at JKM i took the car back to AMD to see if they could see whyit was down on power and running so rich. A VCDS scan showed up a fault relating to the inlet manifold. The garage cleared this fault and asked me t return at the weekend to scan the car again. The second scan showed a CAT inefficiency error?
After the first faut code had been cleared the car started doing this strange boost bhaviour where it appears to boost too high then drop off and then back up again. Here is a video;



The video was taken with constant full throttle.

AMD has said that thiscould be something to do with the flaps in the inlet manifold, but i want to try and get some of your opinions before i start investigating into the wrong thing.

Oh and this does not happen all the time, sometimes i boot it and it goes to 21psi and holds it but more often then not is doing this as shown in the video.

Any help woud be much appreciated. Sorry for the long post  :ashamed:
« Last Edit: November 20, 2012, 06:03:47 pm by bendy »

Offline RENNTAG

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Re: Strange intermitent boost problem - please help :)
« Reply #1 on: November 20, 2012, 10:00:10 pm »
No one?

Offline bacillus

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Re: Strange intermitent boost problem - please help :)
« Reply #2 on: November 20, 2012, 10:11:34 pm »
What dv do you have, a forge one?
Without traction power is nothing!

Offline RENNTAG

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Re: Strange intermitent boost problem - please help :)
« Reply #3 on: November 20, 2012, 10:19:37 pm »
OEM revision D, was fitted about 5 month ago.

Offline bacillus

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Re: Strange intermitent boost problem - please help :)
« Reply #4 on: November 21, 2012, 02:29:10 pm »
Hmm, are you able to log your wastegate duty cycle and boost with vcds?
« Last Edit: November 21, 2012, 02:41:39 pm by bacillus »
Without traction power is nothing!

Offline RENNTAG

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Re: Strange intermitent boost problem - please help :)
« Reply #5 on: November 21, 2012, 05:06:24 pm »
Unfortunately i dont have vcds. car is going back to the garage on tuesday for a proper look.

Has been behaving better today.

I will ask the garage to log the waste gate duty cycle and boost and see what they say.

Do you think it could be  a waste gate issue bacillus?

Offline bacillus

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Re: Strange intermitent boost problem - please help :)
« Reply #6 on: November 21, 2012, 06:11:27 pm »
It's just one avenue to explore and exclude in the troubleshooting list.
Without traction power is nothing!

Offline RENNTAG

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Re: Strange intermitent boost problem - please help :)
« Reply #7 on: November 21, 2012, 06:31:34 pm »
Yes this is true. Wil et you know if i find out any more. Has probably orted itself out now lol.

Offline RENNTAG

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Re: Strange intermitent boost problem - please help :)
« Reply #8 on: November 28, 2012, 09:59:56 am »
^^^^^ Just seen the typo's in that post  :ashamed:

Anyway garage has said it looks like the manifold flap is cauing the problem. Would appear it is sticking due to getting carboned up or something. Has anyone heard of this before?

Offline zerolag

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Re: Strange intermitent boost problem - please help :)
« Reply #9 on: November 29, 2012, 11:04:51 am »
What are your N75 readings?  Could well be the waste-gate actuator.

Eliminate all possibilities of a leak before adjusting the w/g actuator; last option.

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Re: Strange intermitent boost problem - please help :)
« Reply #10 on: December 15, 2012, 02:58:59 pm »
AMD were right, was a problem with the net manifold.

The flaps inside the manifold were getting stiff and and did not always do what they were suposed to.

So now this problem is resloved. on to the next one  :laugh:

Offline DSG_Steel

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Re: Strange intermitent boost problem - please help :)
« Reply #11 on: December 15, 2012, 09:50:44 pm »
Glad you got the problem sorted

How much did it cost to get the manifold flaps changed?

Offline RENNTAG

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Re: Strange intermitent boost problem - please help :)
« Reply #12 on: December 15, 2012, 09:53:50 pm »
To be honest i have no got the bill yet but i dont think its oing to be a cheap job lol