While recently driving my 2007 LS460 (25K miles, with valve recall done) at around 40 mph I floored it to pass and the engine revved like it was in neutral for 3 or 4 seconds (seemed like forever) before the transmission engaged and downshifted, then caught up with the engine rpms, and finally started to accelerate. No other car I've ever driven has taken so long to downshift and accelerate, and I was worried that I might not be able to pass in time. This was unexpected and is a safety hazard.

Apparently this is not an uncommon occurrence, as Lexus issued Technical Service Bulletin L-SB-0033-08 in June, 2008 to remedy this problem.

See this link:
[URL="http://edmunds.com/car-maintenance/tsb.html?year=2007&make=&model=&styleId=100807643&engCode=8VNAG4.6&transCode=AUTOMATIC&mileage=25000&zip=30328&type=tsb"]

and click on POWER TRAIN: AUTOMATIC TRANSMISSION CONTROL MODULE (TCM, PCM) to open it.

If the hyperlink doesn't work, here's the URL to copy and paste into your browser:
edmunds.com/car-maintenance/tsb.html?year=2007&make=&model=&styleId=100807643&engCode=8VNAG4.6&transCode=AUTOMATIC&mileage=25000&zip=30328&type=tsb

Has anyone had this Hesitation on Acceleration repair procedure done? Did it fix the problem?

 

I have,
and its not rev synchro matching like the beemers and most of all Infiniti and Nissan has, i dont see it as being a problem, since you bought a luxo-strato-lounger, and not a 4D sports car.



Lexus makes a very particular car, and its great for doing many things right, but not all of them well.

 

It might help than when your merging onto the freeway traffic, to keep the ECT button on, maybe.

 

This Shouldn't be happening though!!!

 

I have a 2008 LS460. The car sometimes stalled at very low speeds as I was leaving my house. The ECU update was applied in mid 2008. I have not had any issues after that. Merging into traffic on the highway has never been a problem. However I seldom floor the accelerator. Normal steady acceleration gets the car up to 70 mph in a few seconds while merging.

 

I wonder if disconnecting the battery would cause the ECU to reset and resolve the issue. Has anybody tried that?

Lexus should seriously consider making firmwares and software updates available via internet in 2013's LS. It's an outdated technology already.

 

I have the hesistation on acceleration issue. How to fix it?

 

Found a TSB:

http://www.lambros.net/LexusTechInfo...SB-0033-08.pdf

 

My 09 AWD does it too.

 

After my VSR while driving across the country I experienced the same hesitation, acceleration failure, and loud intermittent clanking from the engine. I brought it to another dealer and they stated that " the VSR recall parts are defective and the left lifter is bleeding so it has to be replaced "

 

I had the engine ECU TSIB and the tranny tsib and they worked like magic. No more low idle and no more feeling like the tranny was in neutral at stop lights

 

Basically the performed the TSB I posted up on top???

 

That's the same TSB that I referenced in my initial blog. I'm taking my car to the dealer this afternoon and will let you know what happens.

 

Took the LS460 in this PM to the dealer and the service tech ran diagnostics and found nothing out of the normal range. He then asked me take him for a drive and see if I could repeat the problem and, of course, the car ran flawlessly without any hesitation when I floored it at a variety of speeds.

The tech thought the problem might have been caused by some bad gasoline, since I had refilled the tank after the hesitation on acceleration occurred and it was now running on a different tank of fuel. He said that the fuel I had in the tank now checked out fine but that if the previous tank had subpar octane gas the computer would retard the timing to minimize engine knock, which would reduce power. He couldn't explain what I experienced previously, namely, when I floored it, the engine revved up as if it were in neutral - disengaged from the transmission - and then a few seconds later the transmission engaged, downshifted and the car accelerated. Now that I think about it, the tech might have a point about the gas, because the car felt likeit had much more power today when I floored it than it did last week when the problem occurred. Bottom line: I'll wait until it happens again and write down every detail to enable the tech to better pinpoint the problem. I'll let you know if it happens again.

 

I just had the same problem fixed by Reno Lexus this week. In my case, it was bad news - - both cylinder heads needed to be replaced. I bought my 07 LS new in August 2007. Looking back on it, the car always had a very slight hesitation under heavy acceleration. I thought this was normal. In December 2010, I took it in for the valve spring replacement. After the recall work, my car was losing power all the time. Sometimes it happened in heavy traffic and created a dangerous situation. Needless to say, I was not happy. I took it back to the shop and after inspection, they said the car needed new heads. The TSIB mentioned in this thread was not enough to fix the problem (although they performed the TSIB software update while they were at it). I just picked the car up yesterday and so far, so good. In fact, it runs better than ever - - power delivery is much more smooth.

My problem took a while to manifest itself. I don't put many miles on the car (12,500 after 3.5 yrs) but I must say that I am less than thrilled with my first Lexus experience. Since purchase, I've had the following problems:

1. Dashboard rattle - TSIB for this and dealer did an excellent job fixing the problem.
2. Wind Noise - I performed the jmcraney fix myself and also covered the drain holes on the side view mirrors. This did not eliminate the noise, but greatly reduced it to acceptable levels.
3. Recall to replace fuel delivery rails
4. Interior noise right by my left ear whenever I hit a crack in the pavement or a sharp bump like a manhole cover - service department verified noise but were unwilling to fix it. They said the noise was normal and was part of the side curtain airbag system. A bunch of BS in my opinion but I got over it. I don't hear it when the stereo is playing.
5. Recall to replace valve springs. While performing repair, they also had to replace the serpentine belt that was cracking (after 12k miles - - ridiculous)
6. Cylinder head replacement - discussed above, but while performing this repair they had to replace the water pump that was leaking (really? -- a water pump leak after 12k miles!!)

Lexus should be ashamed of themselves for ever letting my car leave the factory. It's the closest thing to a lemon I've ever owned. In the past, I've traded in other cars for far fewer issues (regardless of whether under warranty or not). The thing is, I love this car. I've got my fingers crossed that it is finally fixed and at least I got the extended warranty with the VSR. Sorry for the length of this post - - I needed to vent.