fault p1031

Andrew · 8 Dec 2019

PlasticMac said:
If '2.300 V' is the voltage on the valve, it would be constant, as no call for flaps to move. I'll try to do a log while driving. Just need a co-driver/laptop operator!
(Like you said though, could all be gibberish!).
Mac.

Hi Mac,

You don't need a co-driver/laptop operator, just put the laptop on the passenger seat, get VCDS to the measuring block screen and set it going, press 'Log' and then 'Start' (from memory) and go for a drive.

But from a safety point of view!!!!!

1. Make adequate provision for the OBD cable to not interfere with your legs.

2. Set the laptop to work with the lid closed (somewhere in Control Panel). Drive with the lid closed or it is too tempting to be distracted. I would imagine driving with the lid open you would liable to prosecution under mobile phone use type legislation while driving.

Andy

Andrew · 8 Dec 2019

Here is a small chunk my log data at higher revs, the 1.6 appears for me too.

Generally speaking the requested value of 0% occurs at anything over roughly 3000rpm, but not always, very strange behaviour sometimes. I assume 1.6 is near enough to 0 for the ECU to be happy it is within operational tolerance.

Andy

PlasticMac · 9 Dec 2019

The flap return (to open) spring is very important then, as important as the flaps themselves moving freely. For me, knowing that the default flap position is open, and that this is spring loaded (and independent of the actuator) is a revalation.
The list of things to check, as well as the obvious suspects, Vacum Valve ( N316), and Potentiometer, should now include, the vacum tubing (15+ year old rubber), the Non Return Valve, and the Actuator.
The test using VCDS to log potentiometer (and flap) movement while applying external vacum (aka sucking) direct to the actuator, is going to be very handy, I think.
Those flaps, and their operation, is a bit less mysterious than it was, to me at least!
Mac.

mrbroons · 9 Dec 2019

Andy's file attached

Dropbox - Error - Simplify your life

www.dropbox.com

lfield · 9 Dec 2019

Andrew said:
No Vacuum = Flaps fully open!

My previous comment in post #68 becomes

Notice the REDIR FAIL! = Nobody has provided a customised label file for this ECU. This means VCDS is allocating labels on a best guess basis based on the nature of the data. Now then if Block 142 is data about the flaps then its got it wrong and 'Load' is inappropriate, conjuring up images of engine load. I suspect that post #26 above is correct in that the first field is 'Flap % Open - Actual' and the second field 'Flap % Open - Requested', therefore a value of 100% = Fully Open and a value of 0% = Fully Shut. (This could all be gibberish!!!).

I think that you were correct with your original post. With no vacuum the flaps are open and the value is~0% hence 'Flap % Close - Actual' seem appropriate as 100% would be be closed.

lfield · 9 Dec 2019

If found this video useful to explain FSI and this one shows the flap moving. It defines the two modes of operation as "statisfied mode" and "homogeneous model". The flap is used to restrict the airflow to use only half the cross-section and puts the engine in statisfied mode. So flap up (vacuum actuated) closes off the lower channel and puts the engine into satisfied mode and flap down (default resting position) opens up the lower channel and puts the engine in homogeneous model.

lfield · 9 Dec 2019

Here is the result from starting the car and pushing the accelerator a few times.

RPM	Load %	Load %
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
1320	33.7	0	ADP. Run
1000	100	100	ADP. Run
760	100	100	ADP. Run
680	100	100	ADP. O.K.
1080	100	100	ADP. O.K.
2680	100	100	ADP. O.K.
3000	100	100	ADP. O.K.
3320	33.7	0	ADP. O.K.
2280	33.7	0	ADP. O.K.
1160	100	100	ADP. O.K.
920	100	100	ADP. O.K.
800	100	100	ADP. O.K.
1480	100	100	ADP. O.K.
2080	100	100	ADP. O.K.
2480	100	100	ADP. O.K.
2880	100	100	ADP. O.K.
2920	100	100	ADP. O.K.
3160	100	0	ADP. O.K.
3320	33.7	0	ADP. O.K.
1720	33.7	0	ADP. O.K.
1040	100	100	ADP. O.K.
840	100	100	ADP. O.K.
2160	100	100	ADP. O.K.
2800	100	100	ADP. O.K.
2920	100	100	ADP. O.K.
3160	33.7	0	ADP. O.K.
3720	33.7	0	ADP. O.K.
3040	33.7	0	ADP. O.K.
1560	68.2	100	ADP. O.K.
1040	100	100	ADP. O.K.
840	100	100	ADP. O.K.
800	100	100	ADP. O.K.
1840	100	100	ADP. O.K.
2440	100	100	ADP. O.K.
2880	100	100	ADP. O.K.
3000	100	100	ADP. O.K.
3120	100	100	ADP. O.K.
3240	33.7	0	ADP. O.K.
3280	35.3	0	ADP. O.K.
2960	33.7	0	ADP. O.K.
1480	100	100	ADP. O.K.
1000	100	100	ADP. O.K.
800	100	100	ADP. O.K.
800	100	100	ADP. O.K.
600	100	100	ADP. O.K.
0	100	100	ADP. O.K.

A few points to note. The expected value is either 0 or 100% and this agrees with the two modes of operation as mentioned in the previous post. The change seems to happen at 3200 rpm. My flaps seem to be moving so both the solenoid value (N316) and the potentiometer (G336) are operational. The issue seems to be that the resting point is 33.7%, which is strange as yesterday it reached 1.6%.

lfield · 9 Dec 2019

Here is the result of manually applying a vacuum.

RPM	Load %	Load %
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	90.2	0	ADP. Run
0	100	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	87.1	0	ADP. Run
0	100	0	ADP. Run
0	100	0	ADP. Run
0	100	0	ADP. Run
0	33.7	0	ADP. Run
0	46.3	0	ADP. Run
0	94.9	0	ADP. Run
0	100	0	ADP. Run
0	100	0	ADP. Run
0	100	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run
0	33.7	0	ADP. Run

Andrew · 9 Dec 2019

Excellent videos.

There is an excellent thread on here from a year last Spring by B4Andra on his FSI project car. One post here shows the dismantled manifold and short video on manually exercising the flaps. I only mention it because it highlights right at the end the role of the spring on the flap rod on opening the flaps when the vacuum is removed.

Andy

PlasticMac · 9 Dec 2019

lfield said:
Here is the result from starting the car and pushing the accelerator a few times.

RPM
Load %
Load %

0
33.7
0
ADP. Run
0
33.7
0
ADP. Run
0
33.7
0
ADP. Run
0
33.7
0
ADP. Run
0
33.7
0
ADP. Run
0
33.7
0
ADP. Run
0
33.7
0
ADP. Run
0
33.7
0
ADP. Run
0
33.7
0
ADP. Run
1320
33.7
0
ADP. Run
1000
100
100
ADP. Run
760
100
100
ADP. Run
680
100
100
ADP. O.K.
1080
100
100
ADP. O.K.
2680
100
100
ADP. O.K.
3000
100
100
ADP. O.K.
3320
33.7
0
ADP. O.K.
2280
33.7
0
ADP. O.K.
1160
100
100
ADP. O.K.
920
100
100
ADP. O.K.
800
100
100
ADP. O.K.
1480
100
100
ADP. O.K.
2080
100
100
ADP. O.K.
2480
100
100
ADP. O.K.
2880
100
100
ADP. O.K.
2920
100
100
ADP. O.K.
3160
100
0
ADP. O.K.
3320
33.7
0
ADP. O.K.
1720
33.7
0
ADP. O.K.
1040
100
100
ADP. O.K.
840
100
100
ADP. O.K.
2160
100
100
ADP. O.K.
2800
100
100
ADP. O.K.
2920
100
100
ADP. O.K.
3160
33.7
0
ADP. O.K.
3720
33.7
0
ADP. O.K.
3040
33.7
0
ADP. O.K.
1560
68.2
100
ADP. O.K.
1040
100
100
ADP. O.K.
840
100
100
ADP. O.K.
800
100
100
ADP. O.K.
1840
100
100
ADP. O.K.
2440
100
100
ADP. O.K.
2880
100
100
ADP. O.K.
3000
100
100
ADP. O.K.
3120
100
100
ADP. O.K.
3240
33.7
0
ADP. O.K.
3280
35.3
0
ADP. O.K.
2960
33.7
0
ADP. O.K.
1480
100
100
ADP. O.K.
1000
100
100
ADP. O.K.
800
100
100
ADP. O.K.
800
100
100
ADP. O.K.
600
100
100
ADP. O.K.
0
100
100
ADP. O.K.

A few points to note. The expected value is either 0 or 100% and this agrees with the two modes of operation as mentioned in the previous post. The change seems to happen at 3200 rpm. My flaps seem to be moving so both the solenoid value (N316) and the potentiometer (G336) are operational. The issue seems to be that the resting point is 33.7%, which is strange as yesterday it reached 1.6%.

@Ifield
Are you sure that the flaps are fully open, physically I mean? If so, the potentiometer would seem to be the likely problem. It must have a pretty hard life, carbon track or wire wound. Could easily be intermittent high resistance giving the 37 reading, or the connector.
Mac.

lfield · 9 Dec 2019

PlasticMac said:
@Ifield
Are you sure that the flaps are fully open, physically I mean? If so, the potentiometer would seem to be the likely problem. It must have a pretty hard life, carbon track or wire wound. Could easily be intermittent high resistance giving the 37 reading, or the connector.
Mac.

I am quite confident that that flaps are fully open. I can try to measure travel of the vacuum actuator arm to be sure. It was strange that yesterday the reading was 1.6%. It only went to 33.7% when I switched to basic settings to do the adaption. At least we can rule out the solenoid value (N316) as the issue is there where I disconnect the pipe and apply the vacuum manually.

Andrew · 9 Dec 2019

@Ifield

Progress of a kind, now at least you can "see" the problem.

If I have this right, (almost too scared to say anything in case I get it wrong again and muddy the waters again), your logs indicate the problem is reported as flaps not fully opening when requested (returning to rest state) after they have been in a closed state.

If so curiously this is the same diagnosis by a VAG specialist in another current thread of a member who also with 'Setpoint Not Reached'.

How do you know the flaps are fully open? It is one thing to test the flaps manually with the manifold sat on a bench out of the engine in isolation, but another when it is back in the engine. In fact the evidence of your two logs points to the opposite and the flaps are sticking mid travel.

I agree the evidence, a consistent 100% Acutal, 100% Requested suggests the N316 and piping is fine, which leaves possibly the Potentiometer or other problem.

I am leaning towards the other.

Andy

PlasticMac · 9 Dec 2019

Is it fairly easy to remove the potentiometer, and then check it's range, manually moving the spindle, with VCDS? If so, it could be ruled in or out, either confirming potentiometer failure or sticky flaps.
Mac.

mrbroons · 9 Dec 2019

I'm happy to do any testing with my similar problem that may move things on and video the progress. So far I think that I'm going to test that the flaps are connected via the rod and then use some EGR3 as a basic way of cleaning the internals given it is at 130k. I will likely go the whole way and video the flaps removal and cleaning (I have a new sonic bath cleaner to try!) but simple things first! Any other things I can test this evening? Happy to run the same tests as above using VCDS first as a baseline for my issue as it's the same as described.

mrbroons · 9 Dec 2019

Andrew said:
In an effort to be helpful I thought I would take a VCDS log of Measuring Block 142 on my what I believe healthy FSI. I included Block 001 for RPM.

View attachment 59586
Edit. I had this next statement completely the wrong way round. Now correct in post #80.

Notice the REDIR FAIL! = Nobody has provided a customised label file for this ECU. This means VCDS is allocating labels on a best guess basis based on the nature of the data. Now then if Block 142 is data about the flaps then its got it wrong and 'Load' is inappropriate, conjuring up images of engine load. I suspect that post #26 above is correct in that the first field is 'Flap % Shut - Actual' and the second field 'Flap % Shut - Requested', therefore a value of 0% = Fully Open and a value of 100.0% = Fully Shut. (This could all be gibberish!!!).

The value of '2.300 V' never changes, whatever it is, likewise for 'ADP. O.K.' in a 15 minute log.

The start of the log (with some columns hidden for clarity).

View attachment 59587

Ignore the first few lines with zeroes, this must be the time between pressing the start log button, putting on my seatbelt and turning the ignition key to start the engine.

To be continued... I am having difficulty uploading the log file as the upload is rejected with 'The uploaded file does not have an allowed extension.' ???????

Andy

I have seen the measurement of 142 and 143 linked to this issue. I'll try that shortly along with 1 for reference

PlasticMac · 9 Dec 2019

It would be great to have a set of resistance values zero (flap open), mid and full scale (flap closed) for a known good potentiometer, so that a suspect potentiometer can be checked without VCDS. Even if yours is not known to be good, it would be be a good start. If the potentiometer can be removed, a VCDS log will confirm it as good or bad.
Good luck!
Mac.

mrbroons · 9 Dec 2019

PlasticMac said:
It would be great to have a set of resistance values zero (flap open), mid and full scale (flap closed) for a known good potentiometer, so that a suspect potentiometer can be checked without VCDS. Even if yours is not known to be good, it would be be a good start. If the potentiometer can be removed, a VCDS log will confirm it as good or bad.
Good luck!
Mac.

Sorry to be a moron, but can I get that from logging 142 and 143 against 1 and running through various engine speeds once warmed up?

PlasticMac · 9 Dec 2019

mrbroons said:
Sorry to be a moron, but can I get that from logging 142 and 143 against 1 and running through various engine speeds once warmed up?

Yes, you can confirm the pots good, or bad that way, but, only if your 100% sure the flaps are moving from fully open to fully closed. Otherwise you have two (pot and flap) potential unknowns, if you see what I mean!

Edit: Also, multimeter resistance readings, for the potentiometer, would be good for those who'd rather not get into VCDS.
Mac.

mrbroons · 9 Dec 2019

Got it, I'll check with long nose pliers first to check for free play (but friction if that makes sense) then do the logging. Hopefully have an answer within the hour and video out later this evening.

lfield · 9 Dec 2019

PlasticMac said:
It would be great to have a set of resistance values zero (flap open), mid and full scale (flap closed) for a known good potentiometer, so that a suspect potentiometer can be checked without VCDS. Even if yours is not known to be good, it would be be a good start. If the potentiometer can be removed, a VCDS log will confirm it as good or bad.

If someone has the wiring diagram for the potentiometer (G336), I will try to take some readings.

fault p1031

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