Rokasgr Posted November 6, 2018 Report Share Posted November 6, 2018 (edited) Hello, i have a lupo 3L 1.2TDI and it have a average 6.5L/100km fuel consumption. I have changed air filter. Engine sounds fine to me. Can someone help me, what should i check to fix this issue? Edited November 6, 2018 by Rokasgr Quote Link to comment Share on other sites More sharing options...
RAB Posted November 7, 2018 Report Share Posted November 7, 2018 Have you scanned it with VCDS? Can you manually move the turbo VNT mechanism? Wheel bearings OK? Coolant temperature sensor OK? RAB Quote Link to comment Share on other sites More sharing options...
Rokasgr Posted November 7, 2018 Author Report Share Posted November 7, 2018 I have changed new coolant temperature sensor and wheel bearings is ok. I need to check VNT. If it is bad how can i fix it? Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 7, 2018 Report Share Posted November 7, 2018 If any diesel car gives low economy, it is usually running a rich mixture (not enough air) or braking effort somewhere/high friction. The computer will keep injecting the same fuel (it doesn't know there's a problem), but not enough air means black smoke, low power, bad economy. Hey, just thought... does the 3L have EGR? Could be stuck EGR? Quote Link to comment Share on other sites More sharing options...
Rokasgr Posted November 7, 2018 Author Report Share Posted November 7, 2018 Yes with egr, but there is no smoke behind and power looks fine i think. My computer shows 6.5l average usage while im driving in city. Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 8, 2018 Report Share Posted November 8, 2018 Maybe no problem...? heavy right foot Quote Link to comment Share on other sites More sharing options...
Rokasgr Posted November 8, 2018 Author Report Share Posted November 8, 2018 When im trying to be aconomic as possiblr i can gey 5.5l/100km... there is a problem somewere. After changing oil, checking vnt,, changing sparkplugs and accumulator and fuel filter i hope i get better resulys Quote Link to comment Share on other sites More sharing options...
RAB Posted November 13, 2018 Report Share Posted November 13, 2018 Again, can you manually move the turbo VNT mechanism? Wheel bearings OK? RAB Quote Link to comment Share on other sites More sharing options...
cj1 Posted November 13, 2018 Report Share Posted November 13, 2018 On 11/8/2018 at 7:44 AM, Rokasgr said: After changing oil, checking vnt,, changing sparkplugs Huh? 1 Quote Link to comment Share on other sites More sharing options...
Feta1994 Posted December 1, 2022 Report Share Posted December 1, 2022 Hello,i have the same problem with my lupo (converted from automatic to manual) 1.2 tdi 3l Quote Link to comment Share on other sites More sharing options...
mk2 Posted December 1, 2022 Report Share Posted December 1, 2022 What ECU are you using? Or did you have a remap? Quote Link to comment Share on other sites More sharing options...
Feta1994 Posted February 5, 2023 Report Share Posted February 5, 2023 My Lupo has Bosch Ecu code is:045 906 019 AE,and never did a remap Quote Link to comment Share on other sites More sharing options...
Joao Posted April 11, 2023 Report Share Posted April 11, 2023 On 12/1/2022 at 12:10 PM, Feta1994 said: Hello,i have the same problem with my lupo (converted from automatic to manual) 1.2 tdi 3l Hello I’m facing the same issue. -all the maintenance updated -new tires with original wheels -manual gear box. I’m working between 1500-2000 rpm -no smoke -the engine performance is really good And it’s hard to be below 5l even in open road. Any suggestions? Regards Quote Link to comment Share on other sites More sharing options...
mk2 Posted April 11, 2023 Report Share Posted April 11, 2023 (edited) Without reprogramming the ECU for a manual gearbox, the ECU will be running in emergency or fault mode. I'm actually surprised that the car works at all, because the throttle demand is decided by the ECU, not the driver (or pedal). With a regular, normal 3L, you select drive and then can plant your foot to the floor to accelerate fast. The ECU decides how much throttle to give the engine, when to back off during a gear change and then how much power to give for the next gear.... etc. If the car works, then some major modifications must have been made! 👍🏻😀 Edited April 14, 2023 by mk2 Typo 1 Quote Link to comment Share on other sites More sharing options...
Joao Posted April 11, 2023 Report Share Posted April 11, 2023 I already bought it as manual, so, I’m not sure if it was reprogrammed or not. I have a dtc regarding the gearbox as it is not installed, however I have no engine error and the engine behaviour looks normal with good performance and no smoke. I thought that gearbox error didn’t impact the fuel consumption. What is your suggestion? To reprogram the ecu to set the gearbox as manual, how should I do? Thanks in advance. BR, Joao Quote Link to comment Share on other sites More sharing options...
mk2 Posted April 14, 2023 Report Share Posted April 14, 2023 I think, but not sure because I have not tried it (3L is VERY rare in the UK), when people do an auto to manual gearbox swap thing, they wire the engine that it is always in Neutral. So it can rev for TÜV/MOT testing in a regular 3L. The gearbox selector is changed so it is always wired for N (and starting). Resistors replace the gearbox solenoids & sensors. So if driving in the start mode the load map will be wrong, because there is no control to advance the injection timing. I'm guessing- I don't know! So if driving the car in start or Neutral mode, the efficiency will not be correct because the system is set to run for not moving with no load(???). Solution is remap or different ECU and different turbo system (same as 1.4 Tdi)? I would very much like a manual 3L... Quote Link to comment Share on other sites More sharing options...
Joao Posted April 14, 2023 Report Share Posted April 14, 2023 Make sense your analysis. I thought it was easier to find that info. I need to keep investigating. There only problem by now is the Fuel consumption (4.8l/100km with very careful) but the car very well in did. Many thanks for your answer mk2. Quote Link to comment Share on other sites More sharing options...
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