P0171 system too lean

Sorry, that was my fault, I gave the wrong block (I was looking at a log on my S3 chasing an issue with a map I had when I fist got it). Block 009 is requested & actual boost. Looks like your RS4 valve (assuming that's what you've got fitted?) is failing. I've seen them spike upto 200Bar on gearshifts but not during WOT like that. However I can't see this being your issue.

Also, your boost is pretty low for a Revo on boost setting 9 - usually they peak around 2.9Bar.

Here's an extract from my car using the same vcds blocks;
Code: 
Group A:    '003                Group B:    '230                Group C:    '118           
    Engine Speed    Mass Air Flow    Throttle Valve Angle    Ignition        Rail Pressure    Rail Pressure    Rail Pressure             Engine Speed    Intake Air    Boost Pressure    Boost Pressure
TIME    (G28)    Sensor (G70)        Timing Angle    TIME    (specified)    (actual)    Difference        TIME    (G28)    Temperature (G42)    Control (N75)    (actual)
STAMP     /min     g/s     %     °BTDC    STAMP     bar     bar     bar        STAMP     /min    °C     %     mbar
301.37    5160    269    98    9    301.5    129.99    129.24    0.75         301.25    5000    14    61.2    2370
301.76    5520    292.64    99.6    9    301.89    129.99    135.59    -5.6         301.62    5400    15    63.9    2880
302.14    5880    309.97    99.6    9    302.28    129.99    128.93    1.06         302.02    5760    16    66.7    2860
302.53    6200    323.56    98.4    10.5    302.65    129.99    132.66    -2.67         302.4    6080    16    69    2800
302.92    6480    312.92    39.6    12    303.05    129.99    132.38    -2.39         302.8    6400    17    71    2920
303.31    6760    324.83    44.7    12.8    303.43    129.99    134.43    -4.44         303.17    6680    17    71.8    3080
303.69    6640    307.92    42.7    6    303.83    129.99    124.28    5.71         303.56    6880    18    70.2    3000
304.09    5400    259.11    40.4    9    304.21    129.99    130.71    -0.72         303.96    5320    18    63.9    3080
304.47    5520    262.42    40.4    6.8    304.6    129.99    131.06    -1.07         304.35    5480    19    64.7    3040
304.87    5640    269.42    40.8    9    305    129.99    132.28    -2.29         304.73    5600    20    65.5    3040
305.24    5800    278    40.8    9    305.38    129.99    137.45    -7.46         305.12    5760    21    66.7    3060
305.64    5840    44.58    19.2    27    305.76    115.94    134.12    -18.18         305.51    5800    21    1.6    2660
 
nluk100 said:
Sorry, that was my fault, I gave the wrong block (I was looking at a log on my S3 chasing an issue with a map I had when I fist got it). Block 009 is requested & actual boost. Looks like your RS4 valve (assuming that's what you've got fitted?) is failing. I've seen them spike upto 200Bar on gearshifts but not during WOT like that. However I can't see this being your issue.

Also, your boost is pretty low for a Revo on boost setting 9 - usually they peak around 2.9Bar.

Here's an extract from my car using the same vcds blocks;
Code: 
Group A:    '003                Group B:    '230                Group C:    '118           
    Engine Speed    Mass Air Flow    Throttle Valve Angle    Ignition        Rail Pressure    Rail Pressure    Rail Pressure             Engine Speed    Intake Air    Boost Pressure    Boost Pressure
TIME    (G28)    Sensor (G70)        Timing Angle    TIME    (specified)    (actual)    Difference        TIME    (G28)    Temperature (G42)    Control (N75)    (actual)
STAMP     /min     g/s     %     °BTDC    STAMP     bar     bar     bar        STAMP     /min    °C     %     mbar
301.37    5160    269    98    9    301.5    129.99    129.24    0.75         301.25    5000    14    61.2    2370
301.76    5520    292.64    99.6    9    301.89    129.99    135.59    -5.6         301.62    5400    15    63.9    2880
302.14    5880    309.97    99.6    9    302.28    129.99    128.93    1.06         302.02    5760    16    66.7    2860
302.53    6200    323.56    98.4    10.5    302.65    129.99    132.66    -2.67         302.4    6080    16    69    2800
302.92    6480    312.92    39.6    12    303.05    129.99    132.38    -2.39         302.8    6400    17    71    2920
303.31    6760    324.83    44.7    12.8    303.43    129.99    134.43    -4.44         303.17    6680    17    71.8    3080
303.69    6640    307.92    42.7    6    303.83    129.99    124.28    5.71         303.56    6880    18    70.2    3000
304.09    5400    259.11    40.4    9    304.21    129.99    130.71    -0.72         303.96    5320    18    63.9    3080
304.47    5520    262.42    40.4    6.8    304.6    129.99    131.06    -1.07         304.35    5480    19    64.7    3040
304.87    5640    269.42    40.8    9    305    129.99    132.28    -2.29         304.73    5600    20    65.5    3040
305.24    5800    278    40.8    9    305.38    129.99    137.45    -7.46         305.12    5760    21    66.7    3060
305.64    5840    44.58    19.2    27    305.76    115.94    134.12    -18.18         305.51    5800    21    1.6    2660
Click to expand...
I can't make sense of that log, but I'm pretty sure it's just a stock valve I checked the part number when I had my manifold off and it was just the stock return. Why would it be requesting 180bar? I'm more confused now lol
 
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2.9Bar on VCDS is 1.9Bar BTW

If you're on a stock valve then it can't hold that much fuel pressure on WOT
 
nluk100 said:
2.9Bar on VCDS is 1.9Bar BTW

If you're on a stock valve then it can't hold that much fuel pressure on WOT
Click to expand...

This gentleman is right! I forget to subtract atmospheric pressure from that reading.
You must post requested vs actual boost and AFR ratio.
 
Last edited:
blondieee said:
where do I get AFR?
Click to expand...

Block 031 bank1 is your "air fuel" . Its not exact, its a little bit off one way or another, but it can give you a rough ideah.
Multiply the values of bank1 by 14.7 and it will be close.(just do it in excel.)

Or in block 002, but you'll need a spreadsheet to convert the raw data into A/F ratio.
 
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torquemaster said:
Block 031 bank1 is your "air fuel" . Its not exact, its a little bit off one way or another, but it can give you a rough ideah.
Multiply the values of bank1 by 14.7 and it will be close.(just do it in excel.)

Or in block 002, but you'll need a spreadsheet to convert the raw data into A/F ratio.
Click to expand...
Ok will do that on way home from work. I use the torque app aswell and I know it requests stoich on idle and cruising and I think 12:1 on WOT. Might not be the same since my settings are in now.. I'll double check.
 
blondieee said:
Even if I have an rs4 it can't hold that much pressure either tho right?
Click to expand...

No, but after quite a lot of VCDS logging of fuel pressure myself I worked out that it's not an exact science and that you do get spikes upwards of 180Bar when you change gear and the occasional blip, but the logs show consistent request of more than 135Bar which the standard valve just can't cope with. I would replace it with an RS4 valve regardless as they are only around £45 and R-Tech will want one fitted anyway.
 
nluk100 said:
No, but after quite a lot of VCDS logging of fuel pressure myself I worked out that it's not an exact science and that you do get spikes upwards of 180Bar when you change gear and the occasional blip, but the logs show consistent request of more than 135Bar which the standard valve just can't cope with. I would replace it with an RS4 valve regardless as they are only around £45 and R-Tech will want one fitted anyway.
Click to expand...
Yeah I plan to do that
 
Why are you changing that? As I said before, I've seen pressures jumping up on gear changes like yours did so I suspect both the sensor and the valve are ok.

Can't read your latest logs as it's asking me to sign in?
 
nluk100 said:
Why are you changing that? As I said before, I've seen pressures jumping up on gear changes like yours did so I suspect both the sensor and the valve are ok.

Can't read your latest logs as it's asking me to sign in?
Click to expand...
https://1drv.ms/x/s!AnDvQxsY08bsgiarQva7KrQqQsXe

Try this, I had already ordered the bit the other day, as I have seen a few people with revo maps have problems with the wrong sensor being put in and apparently the ones from the a3 have a 1 signal and the s3 have 2 signal? I swapped it out with a single signal one (the longer one) and it made no difference, so I just wanted everything to be the best that is in it. The best that can come of this is that It has the best of everything for going down to R-tech.
 
nluk100 said:
Why are you changing that? As I said before, I've seen pressures jumping up on gear changes like yours did so I suspect both the sensor and the valve are ok.

Can't read your latest logs as it's asking me to sign in?
Click to expand...

Before log I was suspecting this sensor because is a known weak part. It is cheap and is much better to be sure about it.
After the log I'm waiting to see requesting vs actual boost because as noticed, you are under a lot of fuel and under stock boost. Only 1 bar if you subtract the atmospheric pressure (1 bar). This would explain your black spark plugs.
But you ECU still thinks you are running lean so, is your lambda sensor properly located? You are on after market downpipe and if the sensor is not inserted enough it will read lower amounts of oxygen.
For a RS4 valve I would say the fuel pressures are quite normal. I still don't understand the asking 180bar but this is a tuner area.
 
Thanks, the new log confirms that the boost is almost stock @ 1.1Bar peak, which is very odd if you're running boost 9 setting.
 
torquemaster said:
Before log I was suspecting this sensor because is a known weak part. It is cheap and is much better to be sure about it.
After the log I'm waiting to see requesting vs actual boost because as noticed, you are under a lot of fuel and under stock boost. Only 1 bar if you subtract the atmospheric pressure (1 bar). This would explain your black spark plugs.
But you ECU still thinks you are running lean so, is your lambda sensor properly located? You are on after market downpipe and if the sensor is not inserted enough it will read lower amounts of oxygen.
For a RS4 valve I would say the fuel pressures are quite normal. I still don't understand the asking 180bar but this is a tuner area.
Click to expand...
Yeah I had ordered it before then anyway just to make sure, it's no biggie, I bought it from supplier for £20 bosch brand.
The Lambda is 100% located properly and in properly.
 
nluk100 said:
Thanks, the new log confirms that the boost is almost stock @ 1.1Bar peak, which is very odd if you're running boost 9 setting.
Click to expand...
And that's what it's actually requesting! If I'm getting too much fuel and not enough air.. you'd think it would be running really rich. But I recreate my boost leak and without the extra air my car runs spot on. I'm past the point of understanding the Revo map. When first on boost, even just cruising around it hesitates like, almost like it's on/off/on/off. I feel like there's nothing left to check but the map.
 
Well, if this is what is requested I would call it case closed. It is a map issue. Maybe the map was written with the conditions present at that moment.
Stop investing and wait till you see a tuner.
 
I dont understand why you dont just find the closest REVO dealer and get the map reloaded if yours is corrupt.
 
paddy said:
I dont understand why you dont just find the closest REVO dealer and get the map reloaded if yours is corrupt.
Click to expand...
Well I didn't know it was corrupt, and I took it to the Revo dealer last week as I explained to get the settings back in, to see if maybe the issue was they had been wiped for a while. Slight improvement but not much. My closest Revo dealer isn't the greatest. I plan on doing this with my day off in the next couple of days, but he isn't the most helpful so not sure if he will tbh.
 
Contact REVO, they did used to have a rep on audi-sport and he helped me out no end when i was stg1 revo. they will get your local guy to pull his finger out and get you sorted. Point them to this thread so they can see the story.
 
nluk100 said:
Thanks, the new log confirms that the boost is almost stock @ 1.1Bar peak, which is very odd if you're running boost 9 setting.
Click to expand...

blondieee said:
And that's what it's actually requesting! If I'm getting too much fuel and not enough air.. you'd think it would be running really rich. But I recreate my boost leak and without the extra air my car runs spot on. I'm past the point of understanding the Revo map. When first on boost, even just cruising around it hesitates like, almost like it's on/off/on/off. I feel like there's nothing left to check but the map.
Click to expand...

I think I have a logical explanation for this.
The map was written taken into consideration the previous existing condition - a boost leak. Now, ECU tries to lower the boost to meet the previous status quo but is still getting a lot of air compared to programmed and it triggers a lean error.
 
The REVO maps are generic written years ago, they are all the same thats why i say just get it reloaded
 
So would it be right to assume revo don’t do any kind of health check before loading a map? Is that not a bit crazy


Sent from my iPhone using Tapatalk
 
torquemaster said:
I think I have a logical explanation for this.
The map was written taken into consideration the previous existing condition - a boost leak. Now, ECU tries to lower the boost to meet the previous status quo but is still getting a lot of air compared to programmed and it triggers a lean error.
Click to expand...
I thought the same that why I went down to the garage. Same problem occurs when 0 0 0 and he said always F9 B9 and timing 4/5. That's always what they do on these cars. I'm gonna go down tomorrow I don't think he will be happy about my suggestion
 
Revo Maps are not car specific. Its a generic map the franchise downloads to your car from Revo HQ. It doesnt take into account anything your car is doing or has fitted. There is a recommended spec but its up to you to meet the requirements of their map not for them to meet the requirements of your set up.
 
Ok so, I phoned Revo today.. they asked for logs etc from main dealer... they also said my settings shouldn't be what they are.. however in between this, I decided to fit my fuel pressure sensor and oooaft! Cars running great, no more hesitation... fuel trims are now at 11% (I suspect because the settings are wrong) also turns out I have stage 2+ .. anyway, car is booked in on Thursday to get the settings hopefully set up properly. Turns out it wasn't all down to the map at all. Fuel pressure is much more steady now.

Thankyou to everyone who helped, Its very much appreciated!
 
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Actually its all down to you so give yourself a pat on the back :) Its your determination that won through. Well done on an interesting thread which we can all learn from. :)
 
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paddy said:
Actually its all down to you so give yourself a pat on the back :) Its your determination that won through. Well done on an interesting thread which we can all learn from. :)
Click to expand...
Thanks. I had a bit of help along the way, definately a steep learning curve!
 
Glad you got it sorted :icon thumright:

You're going to notice quite some difference when they put the 2+ map on it!
 
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