FSI Hesitation - Finally got VCDS

Well, it isn't pretty. Symptoms are an intermittent lack of power which manifested itself to barely being able to move. No obvious rattles or knocks from the engine. Here are they codes, any ideas?

Address 01: Engine
Controller: 036 906 013 F
Component: MED7.5.11 5130
Coding: 00051
Shop #: WSC 00482
WAUZZZ8Z83N020473 AUZ7Z0B2226100
11 Faults Found:
17439 - Manifold Change-Over Valve (N136): Setpoint Not Reached
P1031 - 35-00 - -
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-00 - -
16687 - Cylinder 3 Misfire Detected
P0303 - 35-00 - -
16785 - EGR System: Insufficient Flow
P0401 - 35-00 - -
16395 - Bank 1: Camshaft A (Intake): Retard Setpoint not Reached (Over-Advanced)
P0011 - 35-10 - - - Intermittent
17699 - Coolant Temp Sensor at Radiator Outlet (G83): Signal too Large
P1291 - 35-10 - - - Intermittent
16712 - Knock Sensor 1 (G61): Signal too High
P0328 - 35-10 - - - Intermittent
17733 - Knock-Control: Cylinder 1: Regulation Limit Exceeded
P1325 - 35-10 - - - Intermittent
17736 - Knock-Control: Cylinder 4: Regulation Limit Exceeded
P1328 - 35-10 - - - Intermittent
17734 - Knock-Control: Cylinder 2: Regulation Limit Exceeded
P1326 - 35-10 - - - Intermittent
17735 - Knock-Control: Cylinder 3: Regulation Limit Exceeded
P1327 - 35-10 - - - Intermittent
Readiness: 1010 0101


Dick Chown Award 2016

Firstly, remember that these codes could be old, so save the details into the log in VCDS and then clear all codes, run the car for a short while and then rescan for errors, these will be the most current ones.

Then you have a chance of pinning down the cause.

Steve B
Fuel filter is a good shout, though if there are fuel issues surely the ECU would give lean fuel trims?

I'll reset and go for a drive at some point this weekend and post the results.

Thanks for the advice,


A2OC Donor
I would do the following things in order.

Clean the earth point
Check the spark plugs, my previous fsi wasn't using the right plugs they were much shorter than the originals.

If the plugs are fine then look at the coil packs. Try swapping them over and rescan the car to see if the fault is moving to another cylinder.

Last and worst case scenario which is what happened to me is its a faulty fuel injector which is a common problem with the fsi. Thankfully I only had one that was faulty but it's not a cheap repair.

Let us know how you get on

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Earth point checked and cleaned a couple weeks ago along with a new set of spark plugs. Old plugs showed no signs of running either rich or lean and were in reasonable condition. Injectors is certainly something I intend on checking but all knock sensors exceeding their limit is worrying, something is causing the knock sensors to read high and it's not detonation then there's not a lot else it can be other than, well, knock. The fuel filter is a must though, but i'm sure a poor supply would also through a code. I'll update as I know more.


A2OC Donor
Try swapping over the coil packs and see if the fault jumps to another cylinder. Wondering if it could even be a manifold problem?

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My TDI only came up with a misfire on the diagnostics (my symptoms were hesitation, a lack of power and the engine cutting out) yet when I changed the fuel filter it was all fine again. I don't know if it's different on the FSI though.
Try swapping over the coil packs and see if the fault jumps to another cylinder. Wondering if it could even be a manifold problem?

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Forgot to mention, tried swapping coil packs, the misfire usually stays with cylinder 3.
Discovery - Requested inlet camshaft angle is not following actual, eg. requested is 10-15 degrees and actual is 0....

Anybody know anything about the camshaft timing control?

Okay, I cleared the codes (though I was unable to take her for a drive, insurance has been swapped to the TT while the A2 is kaput) and the returning codes are intake flap, misfire cylinder 3 and camshaft over advanced.

I'm going to remove the belts and rocker-cover and check for any 'sludge' in the oil galleries for the actuator and check the engine timing is spot on. The belts look in good condition but i'll have a proper look once the belts are off. Once reassembled i'll check to see if there is any improvement and if no, replace the camshaft position sensor and see if that makes any difference.

This makes sense given the way is intermittent and literally turns on and off like a switch!
I've decided to update this thread for the many folks on here who seem to have poor running issues with their FSI and I think I'll start from the top.


I'll caveat these by reminding people these are specific to my car, i'll describe them as best as I can:

Upon starting the car with the engine cold, the engine does not always "Fast Idle" like most, I would expect the engine to idle @ 1100-1200rpm slowly falling as the engine temperature raises. This does not happen. VCDS shows the temperatures as low, so this isn't a misreading sensor. When it does "fast Idle" the car drives like I would expect with no hessitation.

The Idle is rough and you can occasionaly hear/feel a misfire.

When driving, the car either drives as i would expect (say 5-10% of the time) with the remainder being very little power (I mean, literally, none) but no obvious signs of misfire. The induction of air is quite obvious but the engine does not increase in speed.

occasionally, upon acceleration the engine will jolt violently, like i'm opening and closing the throttle, but very quickly. Again, it does not feel like a misfire, but like the engine suddenly has, then loses power.

Fault Codes are on the first post.

What do I think is wrong?

Looking at the symptoms and the fault codes, specially knock sensors and cam timing, my diagnosis at the moment is that the engine is not correctly timed or the variable valve timing is not functioning correctly. Following on from this, injectors could well be an issue, however this is definitely the most expensive avenue, hence starting with timing.


After deciding my course of action a particurly bad experience forced me to take the plunge and take the A2 off the road - it really played up to the point where I was sure i'd be getting recovered!

Following information i've obtained from the internet and Autodata, I removed the cambelt covers and inspected the belts. The belts look like they have been recently changed with the only obvious issue being that the exhaust belt was slack.

Once removed, I inspected the tensioners, which also appeared to be new. Oddly, the only part that was not new was the cambelt idler pully, which i suspect was making the nice 'wshhhhh' noise when the engine is running.

Upon closer inspection it was also obvious the waterpump was leaking. The Idler pully and waterpump have been replaced with new items.

Once the cambelt was removed and the HP fuel pump disconnected I removed the rocker cover.

WARNING: The Inlet & Exhaust Cams are located in the rocker cover. Do not try to remove the rocker cover without first removing the cambelt.

As above, this is a new setup for me, an interesting arrangment which follows onto the rockers and valve springs - each rocker has a roller and oil spray, even at 145,000 miles the wear was minimal.

I also removed the oil control valve (N204) and inspected for operation (both connect the pins to a +12v source and ensure movement of the selector) and generally inspected the rocker cover, removed residue gasket material and cleaned.

I am also replacing the cylinder head oil filter, a small o-ring with a 50-micron gauze to protect the oil control valve. I have an idea that as this was very brittle and flat oil presure was making it's way into the head cavity instead of the oil control valve which could cause issues with inlet valve timing.

The Gasket is a gasket paste instead of a solid gasket.

To Do

I'm yet to replace the rocker cover (weather has been terrible) but I will make a video of my method as a mistake here can easily block an oil gallery and starve the top end.

Test and replace the air intake flap solenoid (The flap is free to move, the arm intact)

Replace timing belt and ensure timing is spot on.

Test and post results - next step if no success is the removal and testing of injectors.

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A2OC Donor
In parallel with your analysis and repair I am doing a similar repair on my FSI. Mine seems to lack power above 3000 rpm after warm up. Feels like it lacks fuel.

I have only one error code: 17428 - Fuel Pressure Regulation Control RangeExceeded P1020 - 35-10 - - - Intermittent

My prime suspect is the fuel pressure sensor.
I have removed the intake manifold and have cleaned it. I have also replaced the injectors, fuel
pressure sensor at the intake manifold and the
fuel pressure control valve.
The intention is to avoid removing the manifold once more. The coolant pipe and the thermostat housing was replace last year.

Hopefully I have cured the problem after assembly. If not I will swap the mechanical pressure fuel pump.
I think the only way to really find out is to measure actual pressure, i'd have a look to see if there is a test routine, though with the high fuel pressure it won't be an off the shelf test kit (I think)

There's something else that regulates the fuel pressure i'm sure - have you looked at the measuring blocks for demanded fuel pressure vs actual? (assuming they exist, from memory i'm sure they do!?)

Check the fuel pressure regulating valve shown in SSP 252 - this is for the 1.4 FSI engine but the technology is identical.

THIS IS A REALLY GOOD READ!!!! Explains how the engine enters the fuel stratifying mode

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A2OC Donor
I have read it many times, but I prefer SSP253, Direct Petrol Injection System with BoschMotronic MED 7. :)I have also checked stationaty high preassure but not while driving and during engine load.
It's good that you have checked all those bits etc but I bet the problem will still be there the fault is 17439

I have exactly the same symptoms and that's my only code, google it hundreds of threads on it

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A2OC Donor
Im more interested in resolving the engine performance issues than the error codes. I will resolve this, sooner or later. :)