AdrianPH

An update. After doing several small trips and a couple of 70 mile journeys. I soon found that after blanking off the Evap inlet, the mpg readings were once again excellent, back to the 60+ region for my typical runs. I got an EVAP error PO441 quite quickly when travelling on the motorway, but no running issues, and after a few days of similar mpg readings I bought a replacement EVAP valve from Ebay, in fact I bought two both at under £9 each Although I could not find one listed specifically for my can I just went for the same part number from the old one, 6QE906517, seems to be a popular one for Audi, SEAT, Skoda and VW. So at the moment all seems well and I am starting to get back confidence in my car. Just annoying that I was told it was tested and was fine. Time will tell but at the moment keeping fingers crossed it stays fine. Adrian

Managed to do some testing today. Bought a fuel pressure gauge over the weekend pressure at 3.4 bar around 49 psi so that looks OK. Took the fuel rail off with injectors,checked the injectors were not leaking, also placed plastic tops over the outlet of each one and turned over the engine for around 18-20 seconds and then weighed the tops with petrol in them and all around the same at 9 grams plus or minus 0.02gram, so I think close enough. No signs of leakage around the exhaust to engine manifold, no gas burns around the O2 sensor so not suspecting a problem with air in the exhaust. What I have also done is taken off the Evap to inlet manifold for the time being and blocked the manifold hole. The engine is running fine at the moment with no signs oof the issue so will test for some time the reconnect and see if the issue comes back, not sure if there is a vacuum gauge that can be fitted to monitor that system or not. How the hell does one disconnect the plastic fuel line connectors where the line come up near the engine on the side of the suspension turret? Tried pushing in the clips pulling twisting etc.

Still awaiting my mechanic friend to get back to me. I used the app again yesterday as the fault once again reared it's head with the PID mpg dropping to 36 on a flat motorway journey down the M55 at 63mph. And yes I do think it looses power as the throttle response was not as expected when the problem was showing. When back at home I used the mobile app and it showed a "Pending Fault P2177 Power Train System too lean off idle bank 1". No other indications. Now just thinking out loud and wondering how the PID calculates the MPG reading, and wondering if it is using the injector pulse width together with the road speed from the ECU to work out a figure. The wider the pulse width or 'ON-Time' the more fuel it uses, in which case I wonder if this could be pointing towards low fuel line pressure. I have nothing to test this with and I notice there is no Schrader valve on the fuel line, so the lines would have to be disconnected and a gauge placed in line. So looking what is available to remove the fuel line connectors and test.

The original fault started around April/May when it went in for the CAT, and now we are in Winter I could see no dependence on hot, cold, wet, dry. The car only gets used on journeys over 30 miles. I have to trust that the auto electrician went through testing of things like the 3 coil packs. I certainly do not feel any stuttering for the majority of the driving, even when I can see the mpg drop. I would think that as only having 3 cylinders if one started to miss it would be noticeable. As I said only when the screen started to indicate very low mpg did I notice anything. Last service was in July and it was running fine at the time. I think I need to contact my friend again with the VAG software to ask about any ODB2 work when changing injectors, if it does not need it or he can do it for me I will just swap them.

I am not aware of there being any other codes, even the auto electrician I have had it back to only quoted that number to me, see this previous post on the past history. https://www.briskoda.net/forums/topic/532791-possible-ecu-problems The car is unfortunately still giving poor mpg when it feels like it, very intermittently, many a time it can be fine then on a run it drops, then next time OK. As to engine performance, I do not notice poor performance, then again I am not trying to push the car hard, when it did drop to the low figures I would occasionally get what felt like a miss fire, a sort of stutter. But nothing like that recently. The app I use Torque with the adaptor is ODB2, and I do monitor live the O2 sensor 1 and sensor 2 as mentioned earlier when I think the fault is occurring.

No codes at present. Aftermarket Cat, I could not justify a OEM one at over £1200 for a 10 year old car. The cat was supposedly damaged due to over fuelling? When clear of the problem the car will happily average 60+ mpg on my motorway journeys this is with the aftermarket cat. When the fault is starting it drops to around 45 for the journey (same journey). Previously, during a particular bad run before the fault code light came on, I watched it drop from high 50's to 25 mpg on a straight motorway run. This is the instantainious mpg reading on the small Garmin screen. So back to my initial question, can I just put in new injectors to see if it clears the fault, or are there changes that need to be done via an ODB tool on fitting them? £60 as a try could be better then the £800 plus I have spent already without clearing the fault. Adrian

Just to add a comment, the fault code is not showing at present although fuel consumption has dropped around 15%. When the engine is warm after being on a run, I am monitoring the voltages of O2 sensor 1 and O2 sensor 2 at tick over, I was told to expect the first to cycle between say 1 Volt and 0 volts as the system maintains the correct fuel mixture to the engine, this is not always happening the O2 number 1 sensor stays high and the O2 sensor no 2 is around 0.8 Volts. But sometimes all is OK and No 1 cycles and No 2 drops to probably around 0.4 - 0.5 Volts. The ECU has been checked OK. Checks have been made on the vacuum system for any leaks the exhaust CAT was replaced a few months ago because of this fault. But it is that intermittent, leaving it with a garage has meant I have been without a car for several weeks waiting for the fault to occur and stay log enough for them to find it. So looking myself at replacing/doing what I can. As there are no ports to check pressure on the fuel line I can not check the fuel pressure, but assume if the pressure was low, I would loose power at motorway speeds which does not happen? So always open to ideas for things I could check/try. I have the Torque ODB2 app on my phone but that is about it. Adrian

It is good that you have also suggested that to try as I have started that already. It was a suggestion to me by the auto garage trying to diagnose the fault. It is on 3/4 of it's second tank of Shell petrol and it's second bottle of injector cleaner. The bottles are supposed to be for 60 litres but the tank is only 35 litres so should be close to a double dose of cleaner! I notice one can get the injectors from just under £13 (UKP) up to over £100 each depending on make. From Borsehung B11165 at the cheap end to the Meat & Doria 75114832 at the other end with Bosh at around £80. But I do not know if it is just a matter of fitting new ones or if settings have to be changed? Adrian

I would just like to ask, I have been having issues with the car for some months, very intermittent, fuel economy will drop sometimes, in the past I got the engine light on and a P2177 but not that often. I was wondering if I could have an injector sticking open a bit. So I looked at injector testing on the internet and most were send away for testing costs around £18 to £25 per injector. Doing another search I find one can buy the injectors new for a similar price each. But my question is this, is it just a matter of swapping them or do I need to change settings within the Engine management via ODB2. I ask because when I had a diesel Mondeo each injector had a code that needed to be entered when swapped, I know this is a petrol and may be simpler but I need to ask? Cheers Adrian

I will gladly admit to not being that much of a smart phone user except for basic calls and SMS, a bit of a Luddite if you know the term, I hate all the data collection etc. But I digress. I have used the Torque Pro software and there are no error codes logged in the car at present, so I will see how things go over the next few months. Many of the things the App will do such as 0 to 60 etc I think are a bit useless on the Citigo, but the basic functions will do what I need. I have spoken to my mechanic friend and there are ECU updates, when he worked for a main dealer they typically did them under the warranty period of the car. It was also discussed that the ECU software errors could well have led to an over fuelling of the engine for a period of time which may have led to damage of the catalytic converter. The typical mpg did drop from high 50's to low 60's typically to around 47 for some time prior to the 1st repair. I thank all for your responses and I keep my fingers crossed that all is now well that the repairs costs will have stopped and I am back to basic service jobs. The engine data as in an above post from Jack25 it is a 3-cylinder gasoline engine 1.0 l/44 kW intake manifold injection base engine is TH4 Thanks Adrian

Pass I do very little on this car myself, it gets an annual service by a garage I trust and apart checks to oil, water,wash etc. That I do, which when the car does little annual mileage. It because of all the electronics now I tend to leave alone. The only other issue I have had was a gear shift stiffness which a bit of oil/grease seemed to have cleared. I now have the car back after an "ECU software update", so time will tell in a few months. Perhaps a widening of parameters before a fault is logged. Now armed with the basic software I can do more diagnostic myself. I love the car, for me it is ideal, pity the map software is no longer supported but that is for another thread sometime. I will try the odb2 app later and see if all clear. Adrian Still on phone

Giacomo. Thanks for your message. As far as I remember a base 1000cc engine, I don't have all details with me at moment, I have decided to visit the auto shop to try and get a face to face update. I have had an offer from a mechanic friend who has the VAG software terminal in that he will have a look at it if needs be. Let's see what response I get. Adrian On phone again one finger typing.

AG Falco; Sorry for the brief answer yesterday, I was using my phone and find it a bit awkward to use at times. I have just had a look at the ODBEleven web site and at some of the reviews on Google app store. Am I correct in thinking this is a subscription software, does you need credits to clear faults and find out what they are etc. I do note there are some fancy things that can be done, sorry for the question but at 66 I am probably a bit out of the loop on all these software apps. I have just bought the Torque pro at £2.95 and awaiting installation from the app store so can at least try that on the wife's car. Thanks for your answers. Adrian

The car is still at the auto electrician's went in on the 20th May. So I have no codes but the app will be for me when I get it back. Adrian

I have a 2015 Citigo with around 50000 miles on it. In January I had a engine management light come on, with a weird diagnostic number, I assumed my old reader would not recognise it, but was able to clear it and everything was fine for 2 months. Then the light came on again so I took it to my normal service garage and they did a few readings as suggested it could be the ECU going faulty as they were getting all sorts of messages from incorrect fuelling to wiring issues etc. They did not charge me for anything but suggested I took it to an auto electrician which I did. These diagnosed a faulty catalytic converter, and fitted an after market unit. Approx 2 month later the engine light came on again and it is back with the auto electricians, they are now saying the ECU needs a software update or something similar as it is showing software errors. I am wondering if this may have been the original issue. So I wonder are there software updates for the ECU, can one fit a unit from a scrapped car and have it reprogrammed to my car, Trying to figure what the options are as it seem I am being kept in the dark as I am not getting any feedback when I ring? Is there any good ODB2 reader people can recommend to install on my phone, I have a Konnwei blue tooth dongle that still seems current, not expecting miracles but just one that is up to date and give good readings? Cheers Adrian