It's been like that ever since I got it a year ago. It cuts out as it warms up fully 90% of the time (100% fuel related) as i have a LPG system so I can drive the thing(has left me stranded more than a couple of times before I installed it) Sometimes it runs fine on petrol for some time and after i turn it off and then 10 mins later try to start it up again on petrol, it starts and dies almost instantly or straight up doesnt start at all. When it starts it reeks of petrol and dies like 5-10 secs later. When i switch to LPG it just goes and i have zero problems. I want to be able to drive the car normally on petrol as well(when it goes it goes very well), so I have done quite a bit of work on the car, namely: No error codes whatsoever Replaced lambda Replaced CoolantTemp Sender two times already(not OEM, new, cant find OEM) Replaced plugs two times already Replaced ecu with a digi 3.0 - same prob Replaced dizzy/cap/and the thing that distributes the spark as well(cap and rotor I guess new) Replaced Crank Position Sensor (new, not OEM) and didn't have a torque wrench as i tightened it, made no difference to original OEM one Replaced Fuel Pressure Regulator with Bosch OEM new Replaced Fuel Pump with Bosch OEM new Tried 3 different coils with no result Replaced Fuel Pump Relay and ECM Relay Checked timing and it was a tooth off, timed it right but same as before Checked fuse relay box - took the thing off and apart to make sure - looks immaculate. Checked grounds - all checks out I havent messed with the knock sensors yet, that is litterally the last thing that comes to mind, but it wouldn't cut out the starting. P.S. as it cuts out in driving, tacho still works, switch over to LPG and away you go..... Im so sad as it's running like a 115HP GTI with the LPG system, not the 150 16V i'm searching for. Any help will be highly appreciated.
since its fine on LPG if a bit slow this suggests to me its not a sensor or wiring fault, I would be looking at the fuel rail seals, fuel injectors, pressure regulator or maybe the pump though if it was that I wouldn't expect the rich smell when it cuts out.
Pump and regulator are both new OEM Bosch parts+new fuel filter. I will take injector rail off the car, check seals and clean the rail and have the injectors cleaned and will post the results. Thanks for the tip, the car has previously also had LPG before I had it, injectors are probably in a bad shape - sometimes on cold starts it starts up rough for a few seconds until it gets itself going fine and if i give it some throttle it smokes black smoke as if its really rich, but stops doing it after it warms up a bit.
another thing you can use vagcom/vcds to check your sensor measuring blocks so you can see the readings in real time, the coolant temp sensor for example can be checked from cold to make sure it reads sensible values. heres a thread with ABF label files for the 3.1 and 3.2 ECU to make this process easier: https://clubgti.com/forums/index.php?threads/vag-com-abf-digifant-3-1-and-3-2-label-files.199583/
I've been using my trusty old VCDS from years now. I've replaced the first coolant temp sensor which was the original one because it showed 58C as the rad fans kicked on. Next one i put on showed like 72C as the fans started kicking on (after getting a month old) and the one now shows about 94-98C as they kick on, which i'd count as fair enough, thermostat is new and I've flushed the cooling system. I have just now taken the thing apart and found some interesting stuff regarding injectors. https://drive.google.com/file/d/1-J7mcHeP2YZAq6pmO0G2W73Zho4SIoBn/view?usp=drivesdk
I have been wanting to have the label file since a while now, but I'm not allowed to download them. Could you PM them to me or just upload them over at Google Drive for me?
I have just bought myself a complete injection rail with the injectors from a known good running car (got smacked in an accident) and will install them first thing in the morning and post up. Rubjonny, can you tell me if I would able to see more information on the Measuring blocks with the label files, because I think even not having the label files I can see everything from group 000 to group 006 I believe is the last one, and it's mostly labeled fine. On the good old ABF if I wanted to measure timing I'd need a timing gun, yes?
once you get 10 forum posts your account will be upgraded then you'll be able to download non-image files from the forum the label files dont give access to any further blocks, all it does is give them better labels so if you already know what each block represents it doesnt give you anything extra ignition timing is shown in group 4 IIRC?
I went on to install the fuel rail on the car this morning and it sprung two leaks from the pressure check cap and from one of the two back bolts, I transferred the pressure check cap from my old rail but couldnt fix the leak from the bolt - I think the rail is warped, will be transferring the injectors altogether on the old rail and try again tonight. I'm going to check if timing is been shown on group 004, it should be like 6 BTDC when warmed up and idling or so? And what should it be say at 6000RPM at WOT?
Just installed "new" injectors with my old rail which was pretty clean actually and same thing - hooked it up to VCDS - all values of everything are perfect - as soon as the car warmed up to operating temperature, mashing the throttle shuts it off instantly - I am starting to wonder if my cam chain is timed right or am I going insane. I still havent measured compression - could this be due to low compression - car starts perfectly both on LPG and on petrol? And on Group 004 of measuring blocks I'm again missing the label file - it's them good old 0s and 1s. EDIT: will log temperature from cold to fans kicking in. There isn't any measuring block for knock detecting, or this has to do with the label files again?
After reading a thread on similar symptoms of cutting out and being sorted by replacing the ECU temp sender with Bosch OEM part, I have managed to source a new one for myself which will be here tommorow and I will test again and log with label files - thanks @rubjonny !!!
What I'm getting at group 004 where timing should be https://drive.google.com/file/d/109GOYs482jc8aP75jyTQAr8RNbEqu_Xe/view?usp=drivesdk Can it be that ecu isn't seeing timing at all?
Just had a look at mine, group 4 block 3 is also 255 and looking it up in ElsaWin it says 'not relevant so can be ignored. If you still have the DF3.0 ECU though, this block is shown as ignition timing (calculated figure) so you could plug the older ECU in for a look, though I doubt this is your issue since it runs fine on LPG? Have a look at the throttle position block when the issue occurs again, does it go funny when you stab the throttle? the vacuum line to the ECU is worth a look too, but again not sure how it would still run on LPG if either of those were the problem...
IT IS FIXED!!!!!! New OEM Bosch Temperature Sender (black, part number ends with 040) And a CLOGGED inlet fuel line - just before the fuel rail. It's purring, just redlined it in every gear up to third after waiting it to get fully warm, changed the oil and filter because they were due and the car is PERFECT. I'm so happy right now I just can't describe it. Thanks again, @rubjonny !!!
I just wanted to share that the car is almost straight piped - ABF LHD manifold and original rear silencer, it is just outrageous.