I have an odd issue that has popped up in the past 1000 miles or so. My car is a 2017 with 64k miles. When cruising at light load on flat ground with the throttle barely open (5-10%) and engine RPMS around 1700-2500rpm, I will get slight hesitations and recorded misfires. Worst I have seen on my commute is around 5-15 on CYL 1/3/4 and 20-30 on CYL 2. Commute is 40 miles and about 45 minutes.
I hadn't logged the car all winter as it had been running super well. Been running my 91oct tune with 28psi max observed boost and settles into 27-28psi. I rarely had a chance to use any of that boost due to a pretty snowy winter.
I took some WOT logs this evening on a new tank of 93oct. Only logged out to 6300rpm, but largest timing correction was -2.25 with peak timing being a whopping 4.1degrees. WG Duty looks solid. I haven't smoked tested, but I used some carb cleaner to spray any suspect vacuum leak areas and no RPM drops occurred. I am dropping the link to a couple of logs below:
[Actually linking to the hesitation log as I might have found something off.] Looks like the ECU is dumping fuel sporadically (based on lambda, rail, pressure, and LPFP duty values) at low load and then the ECU immediately trims out the excess fuel (if I am interpreting the data and order of operations correctly.
https://datazap.me/u/arob157/hesitation-log-212023-2-wot-logs?log=2&data=0-1-9-11-12&solo=11
My mod list is pretty long, so I haven't ruled out something being damaged. Going through the usual suspects prior to compression/leakdown test. I installed a Euro manifold when I installed MPI and Vortex turbo at 55k miles. No codes have been thrown or stored related to misfires (did have the SAI codes when the solenoid was dead). Valves were in pretty good condition. I have been running LiquiMoly valve cleaner every 2k miles or so and fuel injector around the same since the turbo install.
Items replaced recently:
SAI Blockoff Plate/delete (hesitation issue was present prior to install blockoff install; SAI solenoid was dead)
Plugs (Running NGK 7347-9s; installed fresh this week; replaced an 8k mile set of 7348-9s)
RS3 Coils (done at 55k miles; L revision which seem current)
PCV Valve and Hose to TIP (installed tonight 4/5; PCV was stock from factory; both AP rev which seems current)
Apologies for the novel of a post. Thanks for taking a look at the logs ahead of time and chime in with any thoughts. Hoping the issue maybe a faulty exhaust/lambda sensor at this point. Maybe something weird with the throttle body or intake manifold.
I hadn't logged the car all winter as it had been running super well. Been running my 91oct tune with 28psi max observed boost and settles into 27-28psi. I rarely had a chance to use any of that boost due to a pretty snowy winter.
I took some WOT logs this evening on a new tank of 93oct. Only logged out to 6300rpm, but largest timing correction was -2.25 with peak timing being a whopping 4.1degrees. WG Duty looks solid. I haven't smoked tested, but I used some carb cleaner to spray any suspect vacuum leak areas and no RPM drops occurred. I am dropping the link to a couple of logs below:
[Actually linking to the hesitation log as I might have found something off.] Looks like the ECU is dumping fuel sporadically (based on lambda, rail, pressure, and LPFP duty values) at low load and then the ECU immediately trims out the excess fuel (if I am interpreting the data and order of operations correctly.
https://datazap.me/u/arob157/hesitation-log-212023-2-wot-logs?log=2&data=0-1-9-11-12&solo=11
My mod list is pretty long, so I haven't ruled out something being damaged. Going through the usual suspects prior to compression/leakdown test. I installed a Euro manifold when I installed MPI and Vortex turbo at 55k miles. No codes have been thrown or stored related to misfires (did have the SAI codes when the solenoid was dead). Valves were in pretty good condition. I have been running LiquiMoly valve cleaner every 2k miles or so and fuel injector around the same since the turbo install.
Items replaced recently:
SAI Blockoff Plate/delete (hesitation issue was present prior to install blockoff install; SAI solenoid was dead)
Plugs (Running NGK 7347-9s; installed fresh this week; replaced an 8k mile set of 7348-9s)
RS3 Coils (done at 55k miles; L revision which seem current)
PCV Valve and Hose to TIP (installed tonight 4/5; PCV was stock from factory; both AP rev which seems current)
Apologies for the novel of a post. Thanks for taking a look at the logs ahead of time and chime in with any thoughts. Hoping the issue maybe a faulty exhaust/lambda sensor at this point. Maybe something weird with the throttle body or intake manifold.
