Hesitation problem at various speeds (TSB info post #159)
#1231
Pole Position
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I drove 45 miles home from the dealership yesterday in “normal” mode, no sport mode as I wanted experience the full effect of the update. Today I’ll take it out and see how “sport” mode performs around town. Before the update, I was using sport mode all the time and, in sport mode, would not experience the slow speed lag or hesitation when rounding a corner then accelerating out of the corner...that’s the condition that’s still an issue. My guess is that sport mode will correct that. Maybe the procedure will be: sport mode around town and normal mode on the freeway since it did not hunt at all on the freeway yesterday. I don’t know how many software updates there have been thus far with this 8 speed, but I don’t think this is the last. Again, thank you for your help and have a safe weekend, Jesse J.
#1232
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I have run top tier Chevron 89 octane from day one, we don’t have 93 in So Cal, only 91 for premium. I’ll give it a try and see what happens. My car is a 2019 RX350L AWD, so my software is different because the shop foreman had to pick out the exact model to compare apples to apples in terms of factory loaded software with similar build dates. The test drive car had the very same drivability issues as mine, and because of that fact, I thought that Lexus was going to say, “ performing as designed.” This canned response is typical with a Ford. I did have to push him to do the TSB update, and the reason he resisted was because I did not use the term “bucking.” The TSB has specific “key” words in the description title; don’t describe the issue properly, and maybe get pushback. I called BS on the very subjective terminology, but argued that we are talking about the same thing or same driving issues. I digress, I will be on the road for a week traveling, so we’ll see how things go. Thanks for the fuel tip and your experience. Jesse J.
#1233
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Interestingly I just finished my first full tank of 87 octane fuel since having the TSB applied and I got significantly better mpg. Pre-TSB I averaged 19-20mpg and with this last tank I was at 23mpg. n=1 so who knows - I don't believe there was too much of a difference in highway vs town driving over this tank - I'll keep an eye on this over the next few tanks.
I'd be interesting if he TSB not only made the car more drivable but also increased efficiency....
I'd be interesting if he TSB not only made the car more drivable but also increased efficiency....
#1234
Driver School Candidate
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took my 2017 rx350 f sport to dealer to have them look at hesitation and drone and shift slow .
- they reprogram the ECU .
car running great without any hesitation or drone noise.
- they reprogram the ECU .
car running great without any hesitation or drone noise.
#1235
Pole Position
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I also have a 2017 F sport. Did they only do the TSB for hesitation and that took away your droning or did they do the exhaust TSB as well?
#1236
Driver School Candidate
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but - car have zero hesitation and no drone noise.
Notes, I told the Service Adviser that all this is on normal drive mode,, not on sport or sport+ ,,
so none hesitation and drone noise on normal drive mode now.
#1239
#1240
Driver School Candidate
#1242
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From Techstream:
USA
L-SB-0032-19 (July 2, 2019)
Vehicle Bucking on 1 - 2 and/or 2 - 3 Upshifts and Surge Between 0 - 46 mph
Canada
TSB L-TCI-5285 (July 29, 2019)
Vehicle Bucking on 1 - 2 and/or 2 - 3 Upshifts and Surge Between 0 - 75 km/h
USA
L-SB-0032-19 (July 2, 2019)
Vehicle Bucking on 1 - 2 and/or 2 - 3 Upshifts and Surge Between 0 - 46 mph
Canada
TSB L-TCI-5285 (July 29, 2019)
Vehicle Bucking on 1 - 2 and/or 2 - 3 Upshifts and Surge Between 0 - 75 km/h
#1243
Driver School Candidate
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Recently bought a new RX350. Coming from a 2013 RX 350 I have noticed that throttle input is pretty stiff on the new 2019. Not sure this is associated with the hesitation people have mentioned, or an inherent design of the Gen 4 RX350's having just a little over 400 miles on it I can't say I've noticed any hesitation while driving. Are 19's coming with ECU flash, or is only upon request?
#1244
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Did you apply the Canada TSB? I may ask dealer check this in next service.
#1245
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Recently bought a new RX350. Coming from a 2013 RX 350 I have noticed that throttle input is pretty stiff on the new 2019. Not sure this is associated with the hesitation people have mentioned, or an inherent design of the Gen 4 RX350's having just a little over 400 miles on it I can't say I've noticed any hesitation while driving. Are 19's coming with ECU flash, or is only upon request?