Foster 525

I have had my 07 RX 350 for 3 weeks now and just turned 1000 miles on the odometer, so the break-in period is done. The final assembly date is February 14, 2006 and builit in Cambridge, ON. When I use any grade of fuel, 87,89,93 octane, there is a moderate throttle lag/hestitation when the gas pedal is depressed 1/4 of the way down when it is moving. When I depress the accelerator further down, 1/2 way, the hesitation is gone. I would prefer the hesitation to not even exist, of course.

Since my car is an early production vehicle, are there any known TSB's on this issue? Does the ECU need to be looked at? I know the RX 330 had this problem, and I thought the problem was solved with the RX 350. I am bringing the car to dealer this Friday, 7/22 for the LPS settings and a few minor things. I hope they can correct the problem.

Any thoughts/suggestions would be appreciated. Thank you.

Lexwang07

So Lexus learning mistakes past, I had an 01 RX300 happened same thing over again! An Lexus transmissions built by another company! I don't know the name company. That's why new ES350 had recalled transmissions problem? I am badly changed buying new car, and stupid throttle lag push a little or hard. Dumb *** 98 Camry 4 speeds transmission. My right feet tired all the time and throttle stiff to running smooth!

tlking98

Same here with a 07 RX350. I have a slight hesitation when pushing the gas peddle. Can be annoying... Let me know what you find out at the dealer.

32kcolors

I haven't seen this with my Canadian-made RX350, unless I'm not perceptive enough.

Update: I can now feel the slight hesitation upon pressing the gas pedal when backing up, but not going forward. Shifting is still smooth.

ChRX350

+1 on the hesitation issue with the 07 RX350. I'm wondering if the ECU can be reprog'd to adjust. Also wondering if the ECU can be mapped to any perf related items... anyone have any ideas?

Larry96815

My RX 330 goes in Tuesday morning for ecu update. I will let you know if it was worth while.

Aloha
Larry

Nostics_RX

Dejavu....I hope rattles/squeeks is not next!!

jamesfabin

I have the same issue on light application of the gas. I also noticed this on every RX I test drove, and it seemed more noticable on the FWD models (I went with the AWD). I just passed 1000 miles and thought the problem went away, but after reading your post I tried it being gentle (which I always do on a test drive) and the problem is present. My guess is a TSB will be coming out soon with a re-program for the transmission.

James

kgreddy

Same thing with my RX350 ... has around 350 miles and i feel hesitation and shifting is not smoth on both up/down shift.

CK6Speed

iTrader: (1)

Sorry guys. I hope I'm wrong here, but I think this is just the nature of the beast. My 04 RX330 already has the latest TSIB transmission update provided by Lexus. I still have some anoying lag on my transmission. The TSIB flah update came out before the RX350 so I doubt that would help the RX350 owners out since they should have the latest transmission programig anyway. If RX350 owners are still having lag issues than the problem will probably never get fixed fully since Lexus had from 2003 to come up with a solution. They already have about 3 generations of transmission ECU updates so its not like they haven't tried.

Larry96815

Chris,

The latest update was 2/06. Did you have that one done? Mine goes in tomorrow for the surgery. I will let everyone know how it works.

Aloha,
Larry

CK6Speed

iTrader: (1)

I had mine done in late March, or early April 06.
https://www.clublexus.com/forums/sho...mission+update

My lag and jerk only seems to happen at lower speeds I think. Hard to tell because it is my wifes car and I don't drive it every day. Off memory though it seems like what some of the above members have said. If you do a partial throttle (About 1/4 way) to accelerate slightly you get no response for about a second or two. If you hit the gas hard it seems to have your typical auto tranny lag though which isn't the issue. Also, when you are going real slow like over speed bumps, and feather the trottle after you clear the bump, it seems to go nowhere, then all of a sudden kick in with a jerk and off you go. Kind of annoying especially when there are multiple speed bumps and and you have to slow down quickly again. It is almost like a novice manual tranny driver at those low speeds

bigbadbuff

Everyone getting the TSB done, please let me know if this helps!!

RHODY401

From what I read elsewhere, the 2/06 update for the 2004 model was just the old one with a broader range of VIN #s unlocked. (it was changed to let other vehicles apply the same patch)

That update made an amazing difference in my 2004. It drives almost like a 2005 or 2006 now.

The fly by wire design (computer controlled instead of a throttle cable), has a bit of a delay associated with it. I suspect your issue may just be normal operation, but get it checked just in case!

Mike

CK6Speed

iTrader: (1)

I hate to say this on a Lexus forum, but I don't think it is the Trottle by Wire, or Drive by Wire system itself. If you drive Honda/Acura cars with Drive by Wire there is no delay. It is either in the way Lexus programs it, the adaptive tranny that can't learn multiple drivers, the choices of gear ratios, the tranny itself, or something else odd going on. I do; however, suspect it is normal for the RX as it is just designed and built that way. For me, as I mentioned once before it is almost like the RX comupter is a notice manual tranny driver that doesn't always let the clutch on soon enough, or lets it out too fast, or is sometimes in the wrong gear. The car is still drivable, but if you are used to other transmissions it it quite obvious someting odd is going on.