[1.2 any] - HELP: 6.9L/100km

[TitusM]

I have an A2 - 1.2 tdi - 2001 ~odo:190k km - with climatronic and servo.

My fuel consumption is 6.9L/100km

 

Next things are new and modified in the last 1000km:

-n75 valve

-maf

-timing belt  (torsion value is now ~1+ but before this the consumption was around the same)

-oil and filters

-oil chain and gears

-thermostat

-water temperature sensor

-new clutch and gearbox basic settings

-new vacuum lines (vacuum drops only on brake pedal -> usually vacuum is around  -0.75 bar)

-egr blocked and not blocked -> the same result

-Breaks seem fine - not stuck

-tires have factory specified inflation ->2.5/2.9 bar

 

I just did a graph for boost and maf. This part seems fine.  The turbo actuator moves freely. Boost seems ok.  

 

Any other tips where to look? 

The car seems to work fine. After n75 change it seems to respond better but consumption is the same.

 

They say I am an aggressive driver but I do not believe I am 3 liters aggressive:) .

I live uphill so every time I commute home I drive uphill around 9km usually at maximum speed but the little one reaches maximum +110km/h.

Edited October 2, 2020 by TitusM
update

[Brukterer]

vor 4 Stunden schrieb TitusM:

I have an A2 - 1.2 tdi - 2001 ~odo:190k km - with climatronic and servo.

My fuel consumption is 6.9L/100km

Hi there, this cannot be true.

An 1.2 tdi takes between 3 to 4 liters of diesel fuel.

May be its galleons or another measure size they have in the UK or in Romania or Siebenbürgen.

 

Now i got it. You look for help cause your 1.2 tdi uses so much fuel.  

Sorry, i have no idea why your engine takes so much.

Edited October 2, 2020 by Brukterer
Ergänzung

[DerWeißeA2]

vor 4 Stunden schrieb TitusM:

-Breaks seem fine - not stuck

 

Seems fine or are proofed fine? Did you opened the brake drums?

What about the diesel filter, has it been renewed throughout the years?

 

[Schwabe]

This seems very difficult.

Your description of the problem is very fine.

First suspicion are the brakes, but you say they are fine.

If you check the Temperatures by VCDS are the temperatures the same for the G2 and the G62?

If you lift the car all tires run free?

Charge air is OK? No leak?

Sorry but i can't read your diagramm.

I have no idea!

Sorry. Good luck!

 

 

[TitusM]

@DerWeißeA2

When the car was lifted on elevator the breaks were free.

I hate the way it brakes (I changed a good pair of brake pads on front because they were awful - changed from textar to ate and now it brakes a little bit better). The rear drums also have no restriction.

All filters are changed - including fuel filter.  (usually I change the filters with the oil - at 15k not 30k)

Wheel brake lines are changed also - front and back. 

 

@Schwabe :

Charge air - or boost seems good. In the graph you can see that the actual boost vs specified boost are very close. This means that the boost is fine. 

I have to check the G2 and the G62. Any idea what group these are in  vcds?

I changed only one temperature sensor the one on top of the engine. Is there another one?

I checked the brakes with a thermal camera. Usually when I arrive at home the front disk brakes are around 90degrees Celsius but this is due to braking.  The drums are somewhere around 40degrees. 

 

I will check the brakes again but this consumption was almost the same before all this.

Today I did 120 km on rural roads - quite some hills to climb. I got 5.6liters/100km.

I would have expected at least somewhere under 5liters but the car was "full" - 2 extra passages.  

 

I get almost the same consumption with my golf 6 1.6 tdi as I do with the audi on the open road. Audi is around 5.6Liters (this is for Golf 1.6 tdi on highway ~135km/h).  The golf consumes usually around 6.4 Liters on the open road but very hard driving (almost race style:). 

 

As a comparison:

The golf dinks around 9Liters - the Audi drinks 6.9 on the same road (on the way home - uphill).

Golf reaches ~140km/h maximum -> Audi around 115km/h maximum. I am starting to believe that the road home might be to heavy on the machines. 

 

 

I will check turbo and vacuum and...fuel system again...and why not the brakes too. 

 

What I never checked...is the CAT - maybe it is clogged although the evac seems free. The "smoke" comes out pretty strong from the tail pipe.  But a I expect a clogged cat to make the car slower and it does not seem the case. 

 

[Romulus]

Smoke + under performance sounds like air deficit: air filter blocked?

 

Has the car still its original software?

[axels]

Hi Titus,

 

my 1.2 drinks normally far below 4l/100km. But in the beginning, when i adopted it, it was far more. 

In my case the brakes were not really free and the mechanical thermostat was always a little open. so the motor was to cool.

In Your case i think the smoke is the key issue. it seems to get to much fuel / to less air.

 

- Control the small hoses for proper fit 

- Look for pressuere leaks in the boost line 

- Have a look on the turbocharger wether it works properly  

- You can try to disable (block) the AGR and see what happens.

[fendent]

Check also leaks in the underpressure (vacuum) hoses.

 

[mäddis]

Please check also the track of the wheels. It has a big influence on consumption.

[Phoenix A2]

 

vor 15 Stunden schrieb TitusM:

What I never checked...is the CAT - maybe it is clogged although the evac seems free. The "smoke" comes out pretty strong from the tail pipe.  But a I expect a clogged cat to make the car slower and it does not seem the case.

 

In what situationen does strong smoke come out of the tail pipe?

If it is black smoke then this indicates too much fuel in comparison to the air mass.

What is the momentary fuel-consumption on the DIS when you drive 100km/h on a flat road without strong wind (engine already with normal temperature, not cold)?

 

What you can also check is the engine-idle-rev fuel adjustment for each cylinder (VCDS: ECU, Measurements, Value Block 13, any value above +-2.0 could indicate a problem with the injectors).

[TitusM]

On 10/3/2020 at 10:06 PM, Romulus said:

Smoke + under performance sounds like air deficit: air filter blocked?

 

Has the car still its original software?

Yep...the car still has original software.

 

I will check the  intake pipe of the filter box. The filter is new <3 months

[TitusM]

On 10/3/2020 at 10:11 PM, axels said:

Hi Titus,

 

my 1.2 drinks normally far below 4l/100km. But in the beginning, when i adopted it, it was far more. 

In my case the brakes were not really free and the mechanical thermostat was always a little open. so the motor was to cool.

In Your case i think the smoke is the key issue. it seems to get to much fuel / to less air.

 

- Control the small hoses for proper fit 

- Look for pressuere leaks in the boost line 

- Have a look on the turbocharger wether it works properly  

- You can try to disable (block) the AGR and see what happens.

I will have to take the turbocharger apart it seems. on the sensors it seems fine (i attached a graph with boost level -actual vs specified and they are very close)

The egr was blocked on my car - i discovered that when i replaced the vacuum lines - the vacuum line that went to egr was blocked. 

 

On 10/4/2020 at 5:48 AM, fendent said:

Check also leaks in the underpressure (vacuum) hoses.

 

I did check and replaces all the vacuum hoses. 

Do you have any idea what is the normal vacuum value for this engine? i am not sure how much it should be. The gauge i have shows ~ -0.7 to -0.8 bar of vacuum.

 

[TitusM]

On 10/4/2020 at 12:43 PM, Phoenix A2 said:

 

 

In what situationen does strong smoke come out of the tail pipe?

If it is black smoke then this indicates too much fuel in comparison to the air mass.

What is the momentary fuel-consumption on the DIS when you drive 100km/h on a flat road without strong wind (engine already with normal temperature, not cold)?

 

What you can also check is the engine-idle-rev fuel adjustment for each cylinder (VCDS: ECU, Measurements, Value Block 13, any value above +-2.0 could indicate a problem with the injectors).

When stationed there is no smoke.  On hard acceleration there is very little black smoke.

 

I will have to check the momentary consumption for flat road. Interesting idea. I must find a flat area:)...I am surrounded by hills. 

 

vcds: Block 13 is 0.20 maximum for one injector - very close to 0 most of them.

 

[TitusM]

Update:

 

I reopened the rear brake drums and one of the pistons was stuck. (I ordered new rear brake pads and everything)

Managed to unlock the piston.

The consumption is now "back" around 5.5 ->6 liters on the same route. 

 

So good catch with the brakes:) Thanks for the guys who suggested. That wheel was not stuck but the brake was rubbing. 

 

I still have to dig forward to find the big culprit. 

 

 

 

[TitusM]

On 10/4/2020 at 12:43 PM, Phoenix A2 said:

 

 

In what situationen does strong smoke come out of the tail pipe?

If it is black smoke then this indicates too much fuel in comparison to the air mass.

What is the momentary fuel-consumption on the DIS when you drive 100km/h on a flat road without strong wind (engine already with normal temperature, not cold)?

 

What you can also check is the engine-idle-rev fuel adjustment for each cylinder (VCDS: ECU, Measurements, Value Block 13, any value above +-2.0 could indicate a problem with the injectors).

Any ideea what other  VCDS measurements to log? (I posted a log with boost levels - I also checked maf and injectors). 

They all seem fine except one interesting thing: 

When the car is in neutral and i read the boost levels(actual vs specified) it seems way off. When I drive the car this values are very close to each other. 

I am trying to rule out the boost part without dismantling it. 

 

[Frickler]

How much is the fuel consumption per hour, when you are not driving? Just starting in my head to exclude possible options....

[TitusM]

14 hours ago, Frickler said:

How much is the fuel consumption per hour, when you are not driving? Just starting in my head to exclude possible options....

At Idle engine in VAGCOM it says: 0.3/0.4 liters

[TitusM]

updates:

I had a little time today (after I changed the engine mounts) and did some print screens:

What I do not understand is no: 023. It looks like it is way off but I think it might be a vcds error.

Group 13  goes to 0.4 on cylinder 3 sometimes but this is in limits. 

I am not sure how to read g72 and g62 (it looks ok). I changed g62 this summer. - Schwabe i do not see the g2 you mentioned.

 

[TitusM]

Also I did a vcds log when I went to pick up the kids.  Downhill and uphill. It was raining so I was a little slower than usual. 

The dashboard sais now 6.

 

You can plot the csv log here (all are free): 

https://kiksu.net/vcds-graph/    or 

https://forums.tdiclub.com/index.php?threads/vag-com-plotting-software.201161/    or 

https://www.logview.net/download-logview/

 

These were the values I could log now. If you have ideas I can log other groups. 

@Phoenix A2, @DerWeißeA2, @Romulus any ideeas what else to log?

I own a vagcom so i can do readings whenever i have time. 

 

Back where i started....6.9Liters: The rubbing brake drum seems to not have had any influence (only better braking).

The car does not feel underpowered like  when a vacuum hose is out. If i disconnect the main vacuum line i can not go uphill with more than 50-60 km/h, I tested that. 

LOG-01-001-007-015.CSV

Edited October 13, 2020 by TitusM

[TitusM]

PCV CCV Valve? 

Is this breather important in fuel economy?

I see some oil around the breather pipe. Does this mean that there is something wrong with it?

 

 

 

https://forums.tdiclub.com/index.php?threads/diesels-do-not-have-pcv-valves.10234/

"Just thought I'd mention that the crankcase ventillation systems employed on diesels are not PCV (Positive Crankcase Ventillation) systems. They are Closed Crankcase Ventillation (CCV) systems."

 

Edited October 13, 2020 by TitusM

[TitusM]

Can the diesel return line to the diesel tank be restricted and therefore have a greater consumption?

Is this even a valid question?

[DerWeißeA2]

Am 2.10.2020 um 21:29 schrieb DerWeißeA2:

 

What about the diesel filter, has it been renewed throughout the years?

 

 

vor 1 Minute schrieb TitusM:

Can the diesel return line to the diesel tank be restricted and therefore have a greater consumption?

Is this even a valid question?

 

[TitusM]

@DerWeißeA2 I changed the fuel filter myself:) this summer. It is surely new. I used MAN filter.

 

About the diesel return line - any idea how to test?

[clekilein]

One Question @Titus,

 

How fast does your car drive in ECO Mode V-Max?

Does it really drives upt to 160km/h until it cuts off in eco mode?

[TitusM]

17 minutes ago, clekilein said:

One Question @Titus,

 

How fast does your car drive in ECO Mode V-Max?

Does it really drives upt to 160km/h until it cuts off in eco mode?

@clekilein  hmm good question.

 

On highway it struggles to reach 130 in eco mode.  160km in eco mode with kickdown or not?

 

The truth is I did not drive one of those before buying it. It was just a dream of mine:)...that now costed me more than the other car (and I still have to fix stuff). I owned a 1.4 fsi Lupo with the same gearbox so I knew what to expect and i had experience with bad actuator and clutch and etc.

 

Right now I want to get out an test it out of the city. I will do a vcds log with speed and consumption and maybe boost.

 

Any hints? What should be the consumption at 130km/h highway speed and how hard should it be to maintain this speed?

 

Hooking up the vcds and going for a drive. I hope it can log such a long way.

[clekilein]

A good engine can easily drive 160 (tachometer) in eco mode w/ a fuel consumption less than max in eco mode.

(No "Kickdown" ofc - this stops the ECO mode)

i dont know max fuel exactly in 5th gear but its around 6.X something.

 

More it cant consume in 5th gear due to the limit maps.

When reaching 160 it should throttle a bit.

 

 

A bad engine struggles with 160 a bit, but less than 140 is totally abnormal.

 

I have 2 ANY A2, one throttles at 160 the other struggles w/ 160.

The second one has always around 0.5l average fuel consumption more. 

I checked many things, cleaned the turbo, oil change, new tires, checking the brakes, injectors... but i had to realize that one engine is a bit better in combustion efficiency.

 

So long story short;

either something is getting hot in/at your car while driving (brakes, tires, gear, ...) or the efficiency of your engine is gone and this probably results in a new/other engine

[DerWeißeA2]

Stupid question: have you reset the average consumption since you got the A2?

[clekilein]

vor einer Stunde schrieb TitusM:

 

Any hints? What should be the consumption at 130km/h highway speed and how hard should it be to maintain this speed?

Maintaining 130 shouldnt be a problem at all, there are not many hills on the autobahn that can push you below 130

 

roughly it should be like this:

80 --> 2.x l

100/110 --> 3.0 l

130 --> 4 l

150 --> 5 l

160 --> 5.6 l

 

While sailing at 100km/h it should show you 0.5 l/100 km or 1.0l at sailing 50 km/h

(Sometimes the display does need some time - it shows you a calculated short term average)

[janihani]

vor 1 Stunde schrieb TitusM:

The truth is I did not drive one of those before buying it. It was just a dream of mine:)...that now costed me more than the other car (and I still have to fix stuff).

 

The ANY is like a woman.
The ANY want's that you spend a lot of time with him, take care of him and sometimes you have to solve the riddle.

 

[TitusM]

UPDATE and lots of details:

 

Here are the logs for this evening run. I did a log with advanced measurements.

Please tell me what you think.

 

You can find the logs here directly as graph (or csv in attachment):

https://log.tunezilla.com/search?part_number=045 906 019 D  ->Click "view"  on the logs from 13-10-2020 and with lots of groups. 

 

LOG-01-011-048-061-07C-105-112-137-152_city_eco.CSVLOG-01-011-048-061-07C-105-112-137-152_NONeco_city.CSVLOG-01-011-048-061-07C-105-112-137-152_external_eco.CSV

 

the log files:

1)city_Eco - in the city with eco mode on

2)external - eco ->out of the city with eco on - and ~15km highway. The highway is not flat - i had a hard time reaching 130 uphill but after that i could reach the 160 limiter.

3)city _non eco -uphill home at the end (when going uphill the consumption jumped from ~4.5 to ~5.3 when I arrived home)

 

Findings so far:

-> cylinder deviation:

It seems that cylinder 3 is a little off compared to the other 2 - it reached almost 1 at a certain point so it might be good to clean the injectors. 

Logging a run like this is useful because you can see that injector deviation can vary pretty much. it is very possible that cyl3 injector has issues. I found a max deviation of >0.9 compared to the others. When idle or short run this was not visible.

 

boost vs speed seem fine:

 

boost pressure vs intake temperature vs speed:

(it could use better intercooler for uphill - the temperature is quite high at the end)

 

Edited October 13, 2020 by TitusM

[TitusM]

1 hour ago, DerWeißeA2 said:

Stupid question: have you reset the average consumption since you got the A2?

 yeeees...I do that pretty often. 

before the long update from this evening i did a reset again. 

[TitusM]

Temperature of engine and wheel when I arrived home from the run above:

 

Turbo intake temperature when I arrived home. It was a little hard to get but this was after 5 or 6 minutes of idle.

 

engine temperatures from above. - the circle in the middle is the oil cap.

 

front wheel disc temperature (same on both sides)

 

rear drum temperature (on the other side 17):

Edited October 13, 2020 by TitusM

[JasTech]

I guess you also calculated the consumption using the actual amount of fuel you put into the car? The computer is sometimes quite a bit off...

[Phoenix A2]

vor 59 Minuten schrieb TitusM:

Here are the logs for this evening run. I did a log with advanced measurements.

Please tell me what you think.

 

You can find the logs here (or in attachment):

https://log.tunezilla.com/search?part_number=045 906 019 D

Click "view"  on the logs from 13-10-2020 and lots of groups.

 

From the logs i can see a torsion value (synchronization between crankshaft and camshaft) that is a bit off spec imho (is that a typo in the label which tells group 004 field 3 ?, because torsion value is group 004 field 4), even if VCDS tells that +-3° is OK.

In the logs the torsion value is between +1.1° to +2.8° for different engine speed/load. 

Ideally the torsion value should be close to 0° (e.g. varying between -1.1 and +1.1 maximum) when the engine runs at nominal temperature.

 

It might be an idea to give torsion value adjustment (another) try.

For others that read this lines, it can be adjusted relatively easy with few tools:

 

[TitusM]

11 hours ago, clekilein said:

Maintaining 130 shouldnt be a problem at all, there are not many hills on the autobahn that can push you below 130

 

roughly it should be like this:

80 --> 2.x l

100/110 --> 3.0 l

130 --> 4 l

150 --> 5 l

160 --> 5.6 l

 

While sailing at 100km/h it should show you 0.5 l/100 km or 1.0l at sailing 50 km/h

(Sometimes the display does need some time - it shows you a calculated short term average)

When I did the test last night I found that the consumption is indeed close to you specification. 

80 ->3.x

100/110 ->4.x

130 and above ->4.5 -in my short test. 

In the graph you can see I was "pushing to the metal" it almost all the time (when i was no afraid of the wet conditions and steep curves). 

 

It is a steep uphill on this highway. I have to test it with the golf but I am sure it struggles to accelerate over 150 uphill.

 

Anyhow when i was going uphill on the way home (like the last 4/5 km) the consumption jumped 1L. So from the total of ~ 50km the last 5 km were very demanding. So i tend to believe i am in a special case...when the road itself is "high consumption".

 

 

10 hours ago, JasTech said:

I guess you also calculated the consumption using the actual amount of fuel you put into the car? The computer is sometimes quite a bit off...

Yes. Good catch. The consumption is actually a little bit higher when doing the calculations with full tank->full tank.

[TitusM]

10 hours ago, Phoenix A2 said:

 

From the logs i can see a torsion value (synchronization between crankshaft and camshaft) that is a bit off spec imho (is that a typo in the label which tells group 004 field 3 ?, because torsion value is group 004 field 4), even if VCDS tells that +-3° is OK.

In the logs the torsion value is between +1.1° to +2.8° for different engine speed/load. 

Ideally the torsion value should be close to 0° (e.g. varying between -1.1 and +1.1 maximum) when the engine runs at nominal temperature.

 

It might be an idea to give torsion value adjustment (another) try.

For others that read this lines, it can be adjusted relatively easy with few tools:

 

 

I was thinking the same thing with torsion value. I will redo the logs tonight with new torsion value.

I did this before the timing belt was changed this summer. It seems that the tools from the mechanic were a little used (but at least is on + side not on -)

As I understood it is important to have the value around 0.5, is this right? PD engine like a little bit of+ there.

 

What about injectors? what do you think?

is is possible that cylinder 3 injector to have some issues? I am thinking of this because 1.2 is a small engine and maybe tolerance should be smaller? Or this might be corrected after torsion value adjustment?

 

(i have to connect the vcds to the car to see the group for torsion value - i will come back with update on this question)

 

I see torsion value above 3 in graph (if the group is correct as you mentioned):

Edited October 14, 2020 by TitusM

[TitusM]

12 hours ago, janihani said:

 

The ANY is like a woman.
The ANY want's that you spend a lot of time with him, take care of him and sometimes you have to solve the riddle.

 

 true...

If you speak nice with it it might work as intended  and might even take you to the seaside  .

[TitusM]

13 hours ago, Phoenix A2 said:

 

From the logs i can see a torsion value (synchronization between crankshaft and camshaft) that is a bit off spec imho (is that a typo in the label which tells group 004 field 3 ?, because torsion value is group 004 field 4), even if VCDS tells that +-3° is OK.

In the logs the torsion value is between +1.1° to +2.8° for different engine speed/load. 

Ideally the torsion value should be close to 0° (e.g. varying between -1.1 and +1.1 maximum) when the engine runs at nominal temperature.

 

It might be an idea to give torsion value adjustment (another) try.

For others that read this lines, it can be adjusted relatively easy with few tools:

 

Modified torsion value:

Logs here:

https://log.tunezilla.com/s/l71v76IY

 

Now is a little bit under 0. (the value is correct on the graph - it is true what you said group 004 field 4 for torsion value)

[TitusM]

I will go to a certified dealership in town to clean the injectors and replace the o-rings.

Hopefully it will not be a very expensive job.

A complete rebuild for an injector is around 100euros (completely new parts from bosch). Since it is only cleaning and oring replacement....

The oring kit cost around 15 euro for one injector but I have no idea how much does the work cost (I am a little bit afraid to diy - i might miss some tools). 

 

I read some more and it seems that it is possible  to have higher consumption because the "holding" o-rings from the injectors are worn and fuels gets loose from return line to the cylinder.

 

Logs to come after injector cleaning and oring replacements (1-2 weeks maybe)

[Phoenix A2]

vor 11 Stunden schrieb TitusM:

Modified torsion value:

Logs here:

https://log.tunezilla.com/s/l71v76IY

 

Now is a little bit under 0. (the value is correct on the graph - it is true what you said group 004 field 4 for torsion value)

 

I think the torsion value is perfectly fine now, no more adjustment necessary.

 

[TitusM]

update:

I readjusted the torsion value to be on the plus side. (new rear brake pads, cables and pistons)

I noticed that cylinder deviation is better now at idle at least - after torsion value reset.  

 

New log: - same run  - but all 3 in one ->all 56 km (city and highway ). 

Non eco...and a bit of race style (sorry i was afraid to go over 180 on  the highway because is not straight - no wonder it's limited speed).

Consumption 5.3 when home....Better than last time and with Non Eco - this is at least weird. It was a little wormer outside. 

 

I will have to redo the same run but with eco on all the way. (i think there will be very little difference in consumption - only in car feel)

https://log.tunezilla.com/s/SXzPAZNj

 

Next I will do this and injector gaskets change. Hopefully the injector deviation will be better.  

 

Edited October 16, 2020 by TitusM

[TitusM]

I did the operation above - with "Diesel Purge".

The cylinder deviation seems to be the same. After warmup cylinder 3 goes on the plus side. 

The filter was not black as in video. The return line was pretty clean. 

 

What I found out and it's weird is that the trunk pump does not seem to work (but the car starts and works) - isn't there a low pressure fuel pump?. 

On the diesel line from trunk (in picture below - the closed loop) there is no movement...I expected to have diesel running from trunk and to go in return line...but it does not. 

The car starts with no problem... but as far as I know there is a small low pressure diesel pump in the trunk that should work. Is the A2 different?

@Phoenix A2 , @janihani, @DerWeißeA2 any idea about the above - trunk pump related? Could this influence the fuel consumption or is this normal - the trunk pump is just a "filter" and level sensor?

Edited October 27, 2020 by TitusM

[janihani]

The Diesel hasn't a trunk pump. It is only a level sensor and there is no filter as far as I know.

[TitusM]

On 10/27/2020 at 11:07 AM, janihani said:

The Diesel hasn't a trunk pump. It is only a level sensor and there is no filter as far as I know.

Thanks,

There has to be a small filter of some sorts to block large things from entering the pipe system ...but if there is no pump it might just the pipes.