Hmm, I don't think so although that's a good point. I'm almost positive it's not slipping, as both times it was very dry, and I didn't see the dash light turn on to indicate that. I've also been driving an M35 for the past 4 years and that thing slips a lot, and it doesn't feel anything like that.Yoda's Master wrote: ↑Mon Jan 30, 2023 8:53 pmtraction control? it is cold so maybe you're slipping?
Thank you for the recommendations! Wow I had no idea the car had learned behavior! This explains a lot considering the 2 previous owners were definitely grandpas. The MPG average when I got the car was 19.2, and mine has been around 17. I will try this reset before I drive home from work tonight and see if it helps. Definitely going to also try the hill thing tomorrow as well, I appreciate the tips and I'll update once I do this.crrraaig wrote: ↑Thu Feb 02, 2023 7:59 amYour first post described it more as a miss (shaking), but in your second post it sounds more like a full cut out of multiple cylinders for several ignitions? I would suspect a miss could be a coil with the mileage, full cut out of a number of cylinders is not likely ignition, I would think.
Because you mentioned Sport mode and suspect transmission, why not do a Learned Behavior reset just to rule that out.
howto-perform-an-ecu-reset-learned-beha ... 69-30.html
Also, consider dogging it to see if it is a engine load issue - heading up hill at a low speed, shift into the highest gear it will take and floor it. I've used this approach to find bad coils on a few of my cars. Good Luck!
Braking
Damn, that's crazy. Did you hear any noise from the cylinder walls getting scratched?Shanehsmp wrote: ↑Sun Feb 26, 2023 11:09 pmThis is exactly what was happening to my car back in 2021 with about 60k on the engine. I thought it was a a transmission issue, but turned out that I have low compression in 3 cylinders....I even get the shake you describe. I know this is an older post, but feel free to message me for more info. I also did a leak down test to determine if it's the valves, rings, head and the air is leaking from the crankcase which would signify bad rings. I also did a visual scope of the affected cylinders and they all have scratch marks and what looks to be gouges in the cylinder walls.
I've yet to tear down the engine, but that will happen sometime this year.
I haven't been able to recreate this issue since the initial post. I just posted an update in the comment above yours, do you think the HPFP could be the problem here? I don't think the car was actually braking, it just felt like that to go from full throttle to nothing instantly. Thinking maybe the car was running out of fuel due to the HPFPfontana dan wrote: ↑Mon Mar 20, 2023 6:55 pmAre you able to recreate this problem for a video? Take a data log of vehicle speed during this event. O2 sensors will tell you if it is running out of fuel.
When you say the car feels like it is "braking" you need to know if the ABS pump is activating in these conditions. I would recommend pulling fuse for ABS and test driving. Scan for codes in all modules.
So the car shutting off on itself was also happening to me...Tryptameme wrote: ↑Mon Mar 20, 2023 6:39 pmDamn, that's crazy. Did you hear any noise from the cylinder walls getting scratched?
So I've been driving this thing every day since the post, and I go WOT pretty much every time I drive it, and I've yet to have the problem happen again. However, these last 2 mornings have been cold, and when I start my car, the engine starts and immediately dies. If I press on the throttle a little bit as it's starting, it's fine. Prior to these last 2 days, all winter when I would start it in the cold mornings it would sound like it was about it die, but recovered right before hand.
I'm starting to wonder if both of these issues are related, and may be symptoms of a bad high pressure fuel pump. Does anyone know of how i can test the HPFP, and does it sound like it could be the cause of both these issues? I'm worrying because it seems to be a huge killer of these cars, and I should probably be replacing it ASAP if it is the problem. But I also don't love the idea of spending upwards of 3k for something that may not be the problem.
Tryptameme wrote: ↑Mon Jan 30, 2023 4:25 amI have a 2012 M56x with 105k miles, bought just a few months ago at 100k from an Infiniti dealer. The car was always dealer serviced and seems to have been maintained pretty great. The thing rides and accelerates incredibly smooth, even at 120+.
But I'm starting to have an issue that's happened twice to me in the last week. When I'm accelerating full throttle for around 5 seconds+, suddenly the car will feel like it starts to brake. Both times it happened on an on ramp, accelerating from ~40 to ~100. Initially I thought it was the IBA being weird, because I was driving directly into the sun. I fully disabled it after that, and it was off when it happened the second time. Now I'm beginning to fear it's something mechanical. No engine codes are thrown, and I don't hear any strange noises from the engine or trans after it happens. I can't say for sure if there was a noise while it happened, because there was music playing both times.
I'm a little bit afraid to cause damage to my engine or trans by replicating this again to try to get more information. But if I do... What should I be looking for to try and debug the issue? I know this most recent time it happened that it was around 100mph, and the tac read a little over 5k. It happens while my foot is still on the gas full throttle, and it definitely feels like it's braking, rather than just taking my foot off the gas.
Does anyone have any clue what could be causing this? It's worth noting I hit a deer and had bodywork done very recently, and they had to recalibrate the safety systems for that. However, I have all the safety crap turned off in the settings, and the IBA OFF button disabling that too. Is there any way it could be IBA still, or would it be mechanical?