I have a '99 GS300 w/ 105,000 miles and have recently began noticing that there is a lag in acceleration. It happens mostly when I've slowed down to around 30 mph to make a turn. After I get back on the gas as normal, the car only downshifts one gear and lags in acceleration around 2,000 - 3,000 RPM until it gets up to around 3000 rpm. It feels like it is lacking the low -end torque it once had. Once it gets over 3000, while all this time staying in the same gear, you feel the torque curve kick back in. It seems that the car has just begun doing this. I remember that it usually will downshift two gears to provide the power it needs. I have to forcefully press into the pedal for it to downshift to the higher gear. I know it's just started doing this...

Has anyone experienced this or have any advice as to what is causing the downshift/acceleration lag?

 

Have you had your fuel system checked lately or maybe Spark plug's

 

I would say as a non-experienced Lexus owner.............is the gas tank full or close to E

 

is there any unusual noise from the exhaust? I got that same problem on my old Accord and it was cracked exhaust & header. That cause disruption to the air flow and might be the reason why you lost the power.

 

just reset the ecu. you might have been babying it, and its learned that over your past driving habits. there isnt anything wrong with your car mechanically, since once you get into the right RPM the car goes. its not spark plugs, cuz that would affect the engine across the board. if it was fuel, then your problem would be it accelerating bad from the right gear, rather that it not going into the right gear at all.

just reset your ecu. easiest way is to take off the negative terminal from your battery.

GL and let us know how it works out.

 

Add fuel injection cleaner to your gas....buy premium gas....then clean your throttlebody.

Pete

 

Thanks,

Throttle body does need to be cleaned and I do need to reset the ECU. I do pretty much baby it and it's probably shocked whenever I do get on the gas...