Poor running FSI and feels underpowered

PaulA2

Well-Known Member
Thought I would post this as very little experience on the FSI. I visited an A2 FSI owner Thursday evening as they asked me to scan their car due to poor running and starting when warm with engine light on too.

Fault codes
Address 01: Engine Labels: Redir Fail!
Part No: 036 906 013 F
Component: MED7.5.11 4628
Coding: 00051
Shop #: WSC 00487
VCID: 122053EE5EA31AB1C8B-5120
WAUZZZ8Z73N025325 AUZ7Z0B2265541

3 Faults Found:
17746 - Camshaft Position Sensor (G40)
P1338 - 35-10 - Open or Short to Plus - Intermittent
17439 - Intake Manifold Tuning Valve (N316)
P1031 - 35-00 - Setpoint Not Reached
16502 - Engine Coolant Temp. Sensor (G62)
P0118 - 35-10 - Signal too High - Intermittent
Readiness: 0000 0000

All cleared and engine run to see which are long term faults and first 2 appeared instantly. I know he has swapped thermostat and a few coolant sensors before due to a previous fault and now this. I have suggested cleaning up the main earth behind the headlight as a no cost fix but wandered if any FSI owners can shed the light?

thanks Paul
 
Hi Paul. The poor running will be down to the inlet flaps not being active -set point not reached. This will probably be the plastic arm from the vacuum actuator that has snapped. Along with the temp sensor causing incorrect mixture (remember the Fsi is extreme lean burn engine).
The arm is not easy to change and requires the inlet manifold etc to be stripped and the flap assembly cleaned. The arm breaks when the load increases due to the flaps being sticky. It is possible for the arm not to be broken and the flaps are just not able to reach the correct angular position -- if your really lucky. You can see the arm at the back of the engine on the left hand side - it you can wiggle it then it's broken. If it's solid then I suggest running sea foam or the inlet cleaning spray from whyns.
Hope this helps mike.
 
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Mike

Many thanks for the detailed response, have sent a link to the forum member so he can look into it.
 
?...If it's solid then I suggest running sea foam or the inlet cleaning spray from whyns.
Hope this helps mike.

I have the same 'not reaching the set point' problem. Can you tell me where to spray the cleaner into manifold? I can't figure out how it should be done.
 
Hi Paul. The poor running will be down to the inlet flaps not being active -set point not reached. This will probably be the plastic arm from the vacuum actuator that has snapped. Along with the temp sensor causing incorrect mixture (remember the Fsi is extreme lean burn engine).
The arm is not easy to change and requires the inlet manifold etc to be stripped and the flap assembly cleaned. The arm breaks when the load increases due to the flaps being sticky. It is possible for the arm not to be broken and the flaps are just not able to reach the correct angular position -- if your really lucky. You can see the arm at the back of the engine on the left hand side - it you can wiggle it then it's broken. If it's solid then I suggest running sea foam or the inlet cleaning spray from whyns.
Hope this helps mike.

Hi Mike, I'm the poor soul that PAULA2 is referring to in his post. I've had a look at the back of the engine on the left hand side & can't see the 'arm' anywhere. Any chance you could PM me a photo or something?

I've had the the MAF & intake pipe off & can see the flaps, they look clean as a whistle but I know this doesn't necessarily mean anything. I can see the BOSCH Actuator unit in front of the inlet with small black pipes coming out the other side at the back of the throttle body but no plastic arm. Can you point me in the right direction??

Also, don't understand the temperature sensor sending back a fault as they've all been changed for new ones (at some considerable 'pain in the ass' to get at) effort!.

Any help much appreciated, cheers

Gf03Fsi AKA - Paul. (Not PaulA2)
 
Hi Paul yes I'll locate a picture for you. I'm confused to one point though - you say you can see the flaps? Have you removed the upper manifold then? As they are buried deep. Cheers Mike be back soon.
 
image.jpg
It is item 17 black plastic top on metal plate the black plastic arm is only just visible down the side of the upper manifold. Hope that helps. Mike ask more if needed.
 
Hi Paul yes I'll locate a picture for you. I'm confused to one point though - you say you can see the flaps? Have you removed the upper manifold then? As they are buried deep. Cheers Mike be back soon.

Mike,

I got the impression from Paul's post that he was referring to the throttle body butterfly valve. Paul, the flaps are much further along the intake stream, very close to where the inlet enters the head.

Matt.
 
Cheers Mike, Matt,

Your right, I've been looking at the throttle body. Will check further along with a mirror or something - it's getting on very tight back there to do anything much!

Will update when I've located it.

Thanks. Paul
 
Paul

I would discount the coolant sensor code as this may be an old legacy issue for now. When I cleared the faults and started engine the only codes to return were the first 2 codes listed.
 
Hi Mike,

Just to update, we've located the actuator & the arm, & like you say, to get at that if it's broken will be a major job.

When you say - "if you can wiggle it, it's probably broken", can you be more specific.

Using long nose pliers we can move the arm vertically up & down which is presumably what the actuator is supposed to do. We removed the big breather pipe above it with the MAF sensor, to get better access & putting a finger & thumb behind & in front I could move it forward & back a little with some resistance but there is no loose floppy feel about it.

With one of us watching it, I started the engine & upped the revs then tried putting it in gear with handbrake on & let out the clutch gently to simulate load on the engine, but neither of us could see the arm moving at any revs? = is it surposed to??

Just need to know because obviously if this has to go into a garage it's gonna big bucks!

Cheers, Paul
 
Becore going to the expense of a garage, i would suggest trying a can of Wynns EGR3 spray available from eBay for around £7.99 delivered.

The manifold flaps could be stuck, by a build up inside the manifold, instead of a broken arm.

Worth a try for the small cost

http://www.eurocarparts.com/mobile/.../petrol-system-additives/?555770160&0&cc5_861

There are usually discount codes about for eurocarparts too.

eBay prices have gone up to £9.95
 
Last edited:
Manhattan where do I spray this.

Mine is giving the 17439 code, and I have read up on it. Mine has a new manifold fitted before I got it and the arm is moving fine.

Can this be reset on VCDS?
 
Manhattan where do I spray this.

Mine is giving the 17439 code, and I have read up on it. Mine has a new manifold fitted before I got it and the arm is moving fine.

Can this be reset on VCDS?

I sprayed mine just before the Mass Airflow Sensor, although i would suggest spraying it after the sensor.

You will see a large pipe with a metal clip either side of the sensor, i used large adjustable pliers to grip the clip and pull the pipe off.

Spray the EGR3 in short bursts whilst someone else is in the car keeping the revs between tick over and 3k.

Use the whole can, then clip the pipe back on.

You can reset the throttle body after via vcds.
 
I sprayed CRC Carburettor Cleaner into the throttle, but I removed the air sensor first.
Did it on the hot engine, holding revs at 2500 by fitting a wooden plank between the throttle and the seat.
I think it helped since the 17439 is gone now.
 
Thank you gents I will try and get some today and get it in there, yesterday I drove it like I stole it and I have to say this morning it drove beautifully, so fingers crossed just a bit sticky in there and just needs a good clean
 
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