Ive posted about this problem before but now it's almost gotten me killed. The car shifts fine but once it gets above 2nd, the car shifts and takes a second before the revs just shoot up for some reason even if im trying to have a chill ride. Yesterday i was pulling onto a main road and gave it 70% throttle to quickly get up to speed but the car just took is sweet time to realize wth I'm trying to do and nearly got me rearended by a semi. Any help would be appreciated, not rlly tryna have to pay lexus's $250 diagnosis fee on top of whatever is wrong. My car is a 2010 is250 awd

 

It's likely a transmission solenoid issue but that would just be a guess. Any mechanic with a mid to high level scanner can get the codes for you but do you have any warning lights on the dash?

 

no warning light, but the car will shift just fine sometimes and then will do this bs. I'm thinking it's a throttle body issue or something, cuz i feel like the trans is fine

 

I have a similar thing with my car, it is an is250 2008 RWD and When the car is in normal drive mode it’s almost like I have to step on the pedal quickly with decent force and give it 70-80% gas for it to hop up to speed quickly, otherwise it just slowly goes up. I have had my throttle body cleaned before and my performance is overall pretty normal. I have found that if you drive it with the paddle shifters you get a nice consistent smooth acceleration, you could also try to reset your ecu and see if that does anything sometimes it can get used to driving habits and feel less responsive.

 

I have a 2010 Lexus IS250 Sport and mine has done this since I purchased it. I've just gotten accustom to it at this point.

 

Problem is that this is a new thing that its been doing, and its very annoying because the acceleration and where i have my foot set at just doesnt match. I attached a video, not sure if it will play, but the car quickly shifts to fourth, and once it does, it goes up a bit in revs, then drops, then goes back up and shifts to 5th, and then the revs shoot back up quickly

 

I have the same car with the same problem and like you said it is really bad when trying to accelerate it would so delayed it was ridiculous. What I can say that I did that worked for me and I don’t have that problem anymore is that 1. I cleaned the throttle body. 2. I clean the intake manifold and the lower part with the valves which just remove the bolts and it pops up and you clean the valves really good bc our cars are notorious for carbon build up which I believe is the problem bc it reduces engine performance. It took me an an hour to really clean it that’s how dirty it was. 3. I used Valvoline Restore and Protect engine oil which is advertised to clean out your engine and remove carbon deposits on your pistons and such which I’ve checked and it’s done an amazing job. All that really worked for me and also cleaning your fuel injectors as well which I used Redline cleaner which I think is really good and so far my car runs better than ever. My advice would be to do those maintenance and clean it up cause it does make a difference

 

Hey man thanks for the advice, but i changed the sparkplugs about 4 months ago, and while i did that i changed the pcv valve, maf sensor, and cleaned the valves from carbon deposits manually. So i doubt its because of that. Im frankly stumped at the moment. Also i have already cleaned the throttle body

 

I believe you need to do a throttle body re-learn after cleaning it
See if that helps...

 

ive done this already too man 😭😭
coming here was my last resort