Hesitant acceleration

[Barry14UK]

Hi Folks,

On a couple of occasions last year I experienced hesitancy when proceeding slowly on light throttle and using only electrical powered momentum but then pressing the gas pedal more nothing happened.  This happened twice today and I was obliged to press the pedal quite firmly whereupon the car accelerated more than I really wanted.  For those of you that are familiar with carb fuelled cars, it was like a flat spot.  The coolant was up to temperature.  This has happened either side of a major Lexus service including new s/plugs.  I have avoided using the E10 petrol and the trip computer showed about 90 miles left, about a quarter of a tank full. 

Has anybody else experienced this and if so were they able to resolve it?

[Vadim]

Haven’t experienced this behaviour so far. Do you drive in “Eco” mode? If so, what happens in normal and “S” modes?

I presume the ECU would readily flash error lights, if there was something really wrong with the powertrain.

It has been 2nd refill with E10 for my car - no issues so far.

[mikey2001]

Barry, was your RX ever included in the low pressure fuel pump recall? Just curious if that may have anything to do with the hesitency.

[Barry14UK]

Yes, always drive in Eco mode.  I have had sports cars and motorcycles over the years but my RX450h does all I need in this mode nowadays.  It's so strange that it has only hesitated a vey few times.  On the last occasion I was keeping slow place in queue with traffic as  approached traffic lights.  When the lights turned green, everybody accelerated and not wishing to leave too big a gap I did what I normally would do pressed the gas pedal a little more but nothing happened.  The distance increased between me and the car in front so I had to press the pedal quite a it more to get a response and then the car took off.  So I then had to brake as I caught up very quickly  with the car in front.  Not the way I like to drive.  This only seems to have happened when a bit of moderate acceleration from electric mode to requiring the engine to cut in.  There has never been a time I can recall when underway with engine that it does not provide instantaneous acceleration.  So I think it must be lag in transitioning to engine power when on electric power. 

I will mention it to Lexus Cheltenham and get their opinion.  I will also take the opportunity to ask whether the car had any due recalls as they know the history of it having serviced it from new.