Pav Posted August 16, 2022 Report Share Posted August 16, 2022 Hi all, I'm new to the forum, but i've had my R33 GTR about 2 years now which already had a plugin G4. I had it mapped last year which was all fine, however the tuner had to dial back the power as he said the ecu was old tech it didn't have much safe guarding features. I have now upgraded to the NGTRX with bigger ID1050X injectors, my question is that on idle the engine seems to run a little 'rough/ lumpy'. Initially with the new ecu it would idle around 850-900 rpm and the afr was reading so lean it was off the gauge, i increased the injection duty cycle from 5 to 7ms this has raised the idle to about 11-1200 rpm now and afr is 12-13 maybe a little rich but still fine. Back to the rough idle, it has stage 2 cams 264 and 272 could this be the reason? Just as precaution i have done a compression test and all cylinders coming back at approx 150psi, i have the R35 coil pack conversion kit and new plugs. Any ideas on trying to smooth out the idle? Many thanks Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 16, 2022 Report Share Posted August 16, 2022 Attach the tune and a short log of it idling. Quote Link to comment Share on other sites More sharing options...
Pav Posted August 16, 2022 Author Report Share Posted August 16, 2022 Hi Adam, Thanks for your reply, please find attached the tune and idling log. Regards Pav Pav - Own.pclx PC Datalog - 2022-08-16 6;31;56 pm.llgx Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 16, 2022 Report Share Posted August 16, 2022 I have made some changes to the idle control settings, the main ignition table, accel enrichment and I have turned off the dual fuel table. I turned off fuel table 2 because there are some cells with -11% in them with zeros on either side, at idle it is bouncing between the -11 and zero. Did your old G4 not have the open loop AFR table enabled? It is very odd for that to be disabled with a GTR and that probably explains why the dual fuel table is so extreme. This should really be enabled before you re-tune, but it will likely through your fuel tune out quite a bit. Pav-Own idle changes.pclx Quote Link to comment Share on other sites More sharing options...
Pav Posted August 17, 2022 Author Report Share Posted August 17, 2022 Hi Adam, Thank you for the changes, i will save it to the ecu tonight and let you know how i get on. Regarding the afr, the can lambda is connected and working. How do i enable the open loop and if i do it will it be safe to drive? I ask because im having it properly tuned on a dyno once i have sorted all these little adjustments such as the idle etc, or is it best to leave it to the tuner to turn it on? Quote Link to comment Share on other sites More sharing options...
Pav Posted August 17, 2022 Author Report Share Posted August 17, 2022 Hi Adam, Just tried the new changes and there is definitely a noticeable improvement in the idling but it is still uneven. I forgot to mention yesterday that also as i increase the rpm through the rev range the same 'idle bounce' is also there, almost like a misfire. I'm quite sure its not a misfire, as the coil packs are firing as they should and i have used the pclink to test each coil individually. Do you think it could be to do with the timing settings, they have copied as per the previous G4 was setup. Also i have added a Bosch IAT 0280130085 but can't find that p/n in the selection list. Both fuel and oil are being monitored by the Bosch 0261230341 i believe these are both functioning correctly. I have attached 2 logs, first is from cold start and the second is with engine at operating temp. Please let me know what you think. Kind Regards Pav PC Datalog - 2022-08-17 6;39;50 pm.llgx PC Datalog - 2022-08-17 6;49;15 pm.llgx Quote Link to comment Share on other sites More sharing options...
Pav Posted August 17, 2022 Author Report Share Posted August 17, 2022 Hi Adam, I've also just realised my can lambda isn't working, in runtime values i'm getting the codes 16, 33 and 34. I have checked the help section for these codes and it says possible wiring fault, but i am definitely getting power to the lambda controller, i have even tried another bosch lsu sensor and still the same errors. I have wired it as per the instructions using the preferred method on the quick start guide. Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 17, 2022 Report Share Posted August 17, 2022 5 hours ago, Pav said: Also i have added a Bosch IAT 0280130085 That uses the std Bosch NTC calibration. ECU wise the idle control looks reasonable now. You could probably drop the dashpot offset so it is not so slow to come back to idle after you lift off. Cant see the misfire or reason for it in the log. 4 hours ago, Pav said: I've also just realised my can lambda isn't working, in runtime values i'm getting the codes 16, 33 and 34. 4 hours ago, Pav said: I have wired it as per the instructions using the preferred method on the quick start guide. These errors are common with a noisy power supply. So you have the lambda on its own relay connected direct to the battery, or is there other stuff sharing the same supply? Quote Link to comment Share on other sites More sharing options...
Pav Posted August 18, 2022 Author Report Share Posted August 18, 2022 Hi Adam, Lambda is on its own replay, but i have taken the 12v supply and the switched 12v from another source. I will run a clean supply directly from the battery and see how it goes. Yes as you mentioned the idle is much better now. Regarding the misfire, i don't think it actually is a misfire, but as it was doing at idle the revs are not stable increasing through the rev range, they are 'bouncing' as i raise them from idle, especially on slow acceleration. If i blip the throttle quickly its not so noticeable, its difficult to try and explain it in words. I've uploaded a short clip of the pclink, at about 1800rpm you can see the rpm fluctuating and the engine tone is different. Video 2022-08-18 at 8.51.08 AM.mp4 Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 18, 2022 Report Share Posted August 18, 2022 That sounds much like cam lope to me. Quote Link to comment Share on other sites More sharing options...
Pav Posted August 18, 2022 Author Report Share Posted August 18, 2022 Possible the timing could be off? Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 18, 2022 Report Share Posted August 18, 2022 I assume you are talking about cam timing? Hard to tell from here... But doesnt sound to unusual to me. Obviously you need to set your base timing. Quote Link to comment Share on other sites More sharing options...
Pav Posted August 24, 2022 Author Report Share Posted August 24, 2022 Hey Adam, Yes base timing was slightly out, thank you for mentioning. Also the connector on injector 6 wasn't seated correctly so i guess the combination of the 2 would make it run as it did, all good now. However it does still smell very very rich and lets out a bit of smoke on hard acceleration which appears to be unburnt fuel, but might just be me overthinking??? Quote Link to comment Share on other sites More sharing options...
Adamw Posted August 24, 2022 Report Share Posted August 24, 2022 It will need the tune checked before you give it a hard time. G4X is quite different than G4. It will be close enough to run, but I wouldnt be confident the fuel tune will not need tweaks. Quote Link to comment Share on other sites More sharing options...
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