wakebord99

Hello everyone-

I have seen a lot of forums about hesitation when accelerating from a stop, which appears fine on my car.

My car shutters when accelerating 20-30% throttle in nearly any gear but it's most noticeable above 75 mph between 2000-2300 rpm. I have no proof but it feels like the transmission is trying to determine if it wants to shift or not. Once the car downshifts it's fine.

I have cleaned my MAF Sensor but that made no difference. I need to change the plugs but since the car never misfires and is fine at all other RPM ranges i don't feel like this is the issue. I should also replace the fuel filter but again i would expect idling issues with this.

Does anyone else share this problem? Anyone have a recommended solution? I did stop by the dealer and they told me there are no updates to my ECU/Trans Comp but he didn't plug anything in.

pa06810

I have the same problem once in awhile. Make sure to only use premium, they seem to be very octane sensitive. It feels like torque converter shutter. I think the knock sensor sends a signal to torque converter that confuses it . I put in some regular for a trip from Ct to Ohio and was sorry for it, stupid I know. It went into shutter once in awhile which can be remedied by making the transmission down shift. On premium, it only happens every other day or so, livable. The most octane sensitive i`ve ever owned...2011 Model. I did put in an update which helped a bit.

Lynzoid

for dem books lol...

wakebord99

Thanks... i do use 93 octane

sktn77a

iTrader: (2)

RWD or AWD?

I used regular gas in my 2007 for 3 years with no symptoms/problems.

213374U

IMO you're asking for trouble. Regular octane fuel tends to have pre-detonation problems in engines with CR over 10:1. Our LS' engine operates at 11.8:1.

But by all means, keep doing it and post back when it finally blows up so we can see how many miles it took

sktn77a

iTrader: (2)

Ever heard of knock sensors and adaptive ECUs?

wakebord99

Thanks for your feedback all-

By the sound of it this isn't a common issue. I'll be doing all the regular maintenance on my car and report back if i have found a fix to the problem.

jasone36

wakebord99, there is a TSB for this issue.

Search my previous threads for the exact Lexus TSB number.

WNYPAT

I had a similar issue at highway speeds. Turns out there is a TSB for AWD cars that requires the front axles be replaced. I had this service performed free of charge and it is smooth as silk now.

Lynzoid

no, no and no....
1. use Toyota D4 inj. cleaner EVERY 7,5Kmiles, otherwise the DI spray pattern is waay off and tfsi system cant sustain correct ultra-lean fuel cloud. (not regular inj cleaner! ONLY D4 cleaner works! also that is why 'inj maint req'd' signage is there! it's direct injection, not regular inj)
2. use decent gas
3. use tgmo 0w20
4. check your engine mounts (do you have cold start vibration thru the body?)
5. check the fuel strainer in the tank -> this one's for the 60+mph shudder!
6. check batt voltage under load
7. problem gone

had this, drove me mad, post-tsb ecu firmware. fixed - read up

Lynzoid

this guy also had highway speeds chugging

roadfrog

Not available in North America. The only product offered by Toyota here is Toyota Complete Fuel System Cleaner. That's why most folks here resort to Techron and the like.

Lexuslsguy

Techron is just not a very effective cleaner. Very safe but not particularly great at cleaning injectors. Many other products out there are much more powerful. Even the Berryman B12 stuff is a lot more concentrated then Techron.

https://www.amazon.com/Berryman-Chemtool-Carburetor-Treatment-Injector/dp/B000CCMNAG

WNYPAT

If your car is AWD, depending on the year, there is a TSB describing your exact complaints. Before I went ripping things apart and cleaning them, like the injectors, I'd try to chase down the easy leads first: like TSBs. It'd be helpful to tell us more about your car: Year and RWD vs AWD specifically.