batdude

I hate posting in threads filled with stupid posts....this ins't a synthetic oil or brake fluid issue.

This is becoming a BIG problem in my 2015. Just shy of 2000 miles.

Typically, this is a RIGHT TURN, 1400-1700(ish) RPM issue where the car pretty much has a complete loss of power for 1-2 seconds.

Today it was a freeway on-ramp where i had a yield sign - and needed to hustle to beat the 20 cars turning left across traffic also entering the same ramp. i gave the car a bit more throttle and it slammed into gear pretty hard (seems to me to be a 2-3 upshift - but i didn't have that display up)

i discussed with my dealer the other day - actually had him note it on the WO - but didn't let them do any troubleshooting or anything (just document that the car is doing what I'm saying)

Frankly - I'm disappointed in the vehicle so far.

My 2008 IS-F was a more fun car to drive TBH - and never had a single issue like this where it's obvious that something is seriously wrong either with the ECU or Transmission control programming or something.


Has ANYONE gotten headway with identifying the root cause and corrective action to fix this issue?

Also - how many of you are experiencing it?


Thanks!

doug

rjmalm

Yes I have this now and then but have not been able to capture the BIG 2 second one on video yet. Did have 2 large stalls/dips in 6 months. Yes they were always after removing some amount of steering angle. I have a GoPro pointed at the rpm and multi function display and am waiting for a clear large dip. These often happen 2nd gear manual mode, about 1800 to 2000rpm for me. Same in auto but I have not have the multi function display showing the gear. The link below shows a small one. Notice the orange acc indicator increases and the rpm dips (torque convert lock point). This has been discussed in several threads but no solution has been posted except by ISF001 posted a workaround. One should attempt to avoid this rpm area, use manual and accelerate through it in 1st before going to 2nd and keep the revs above 1800.

ISF001

I am sorry to hear about this issue. No...I do not have anything like this, but how are you driving the F?

Are you a spirited driver? I ask because the ECU in the RC F, like the IS F, will train based on your driving habits. I had this issue with my 2012 IS F for nearly 2,000 miles until I started to drive it more aggressively.

However, if you are driving in normal mode versus sport or sport +, you will experience this kind of lagging performance.

I suggest that you try driving the F in manual, sport/sport + and report back. It should be immediately responsive. I RARELY use auto. It should perform like this:

ISF001

I watched RJ's video. If you are driving in Atkinson cycle at very low rpm and then put in a request for increased horsepower, the RC F will "hunt" for a gear and then deliver.

Remember: this engine is designed to rev high. It wants to be driven at 4,000 rpm and above.

Maintain higher rpm and you will not have an issue. This is the RC F--a muscle that really wants to be flexed all the time. It simply was not designed to be proficient at lower speeds in automatic with Atkinson cycle engaged.

Direct shift (manual) in sport or sport + will not under deliver. Auto sport + will make you look like a maniac in traffic.

ba2sy

iTrader: (1)

I think I have the same thing based on your video. There's that delay in normal mode as if it's on Eco mode. If you want faster response, go for Sport or Sport+ modes. If you still have that problem, then, there's something wrong. Another you can do is add an Apexi TC and put it on Purple or Red modes. I was testing mine last night and it was responsive. Some Lexus SC300 thought I wanted to race because my car was jumping back and forth. Then, he freaking bolted wanting to race me. Lol

Ryanmcd

So your below 2k and gas it and it dips for 1 second lol. Why are you EVER below 2k unless your going 80MPH, would you drive a stick ever below 2k RPM and floor it? I just think most people don't know how to drive or are trying to make this drive like a Camry or something, this car is NOT tuned to run like that it's tuned for TOP end that's why peak power is at redline.

I have 8k miles on my car now and NEVER had anything like this come up ever, no fuel pump no hang up in RPM and I need new rears already if that tells you how I drive the car.


Watching over the video, you have about 20% TPS then you go to 0 so the car shifts a gear then you floor it, WTF do you think's going to happen and who drives like that? A car cant fix a bad driver.

johnnyreb

I remember rite after i had mine installed & i was waiting at the red lite & wasn't really paying attention & was on the phone & just touched the gas & it squealed the tires & was really jumpy. I couldn't believe how much of a difference it made, especially in 1st & 2nd, it's really jumpy. I LOVE IT

batdude

i think what I'd like to do is figure out how to get the ECU in my car completely reset.

then i'll figure out a way to video the behavior.

I don't think - at all - that this is a "how I drive" problem. For now, i spend most of my time just in drive - not in sport or sport + --- i'm still learning the cars behavior. On my 08 F - i drove it in sport every single time i started it.

I'm a fairly aggressive driver - keep in mind i drove a 2008 F for 7 years (!) and for what it's worth.... my thoughts:

(a) this is not a gear hunting issue
(b) this is a timing/ECU issue - aka "engine" vice "trans" - again, my thoughts

my car had 96 miles on it at delivery. it was driven by the dealership GM --- i doubt he drove it like a pansy. (LOL)


doug

corradoMR2

Did you try disconnecting the negative terminal of the battery for a couple mins then reconnecting?

LRCSALES

iTrader: (1)

i was going to say this. Maybe the Apexi throttle controller will help him if this does not clear it up.

JCtx

The same thing happen to me once so far. And I ALWAYS drive in manual mode in sport or sport+. The problem is at low rpm/speed when you need to move to another lane, take off quickly after a semi-stop, etc. It could be many things, from change from Atkinson to Otto cycle, when torque converter locks up, torque vectoring diff setting causing ECU confusion when turning, or a combination of the above. But whatever it is, it's a programming issue. In general, this is not a big problem for me since I rarely drive in heavy traffic, but one of the many things that is very un-Lexus-like on this car. When the tranny slammed into gear (with the car I cut into almost slamming on my tail too due to the delay), wy wife said 'what the ****** was that?' So now I'll downshift to 1st if I ever need to make another such slow speed quick maneuver. I don't have a problem anywhere else due to always using manual mode. The only annoyance is the converter locking up every time you're accelerating in 2nd gear past 1,800 to 2K rpm with a jerk (dip), but I'm used to that by now. And no, this is not something a throttle map controller fixes. In my case, it's on the contrary; the tranny would only slam harder into gear with more throttle. What fixes it for the most part regardless if auto or manual, is using sport or sport+, and learning how to avoid the rpm/gear areas where it can happen. This is another issue Lexus needs to step up to the plate and fix it.

EDIT: What auto mode users can do is downshift with the paddles to avoid that rpm range when needed, and then press (and keep pressed) the right paddle for a second for auto mode to reengage immediately. Hope this helps.

papasmurf1

ive felt some hesitation when I step on it a few times mostly on the freeway didnt really pay attention to what gear or rpm Ive started always driving in sport + hasent happened since......anyone have an idea if this could be a fuel pump issue? not a mechanic just know some people have been having issues with the fuel pump

rjmalm

You made some very good observations.

We dont have a case to present to Lexus until some RC-F owners can document exactly how to recreate dangerous long pause over and over (not just a small dip which we know how to do) or worst case someone finally gets hurt.

Yes we can use a workaround, but someday one of us could be hurt or at least damage our car.

mjeds

I pulled the negative battery cable for 10 minutes and it seems to reset mine, the response was night and day.




I have also found that Sport + mode floor it then brake hard a couple times and it wakes things up, though that is probably best done on a back round..