qewani1

LS400 2000 model,
I have noticed that throttle body Plate does not open fully at all. I think something is wrong? any one have same problem.

This is the maximum throttle body Plate opening in my car when i turn using hand the throttle linkage to maximum open position.

My problem/question is similar to what this person having.
http://www.youtube.com/watch?v=I3xXifUAd18

qewani1

i had seen several videos on youtube about throttle body, i have noticed that all of them opens maximum with full acceleration pressed. what could wrong with my car?
BTW no CEL/DTC.

PureDrifter

iTrader: (10)

are those videos specific to the LS?

in NA cars it isnt unusual because past a certain percentage of opening there's no restriction. also, is that opening done manually or via the electric motors in the DBW system?

qewani1

i could not find any lexus throttle body videos on youtube. Opening is done manually by turning the throttle butterfly.
PureDrifter,
you have LS400 why don't you check your car' s throttle body and report back.

qewani1

Repair manual says that standard throttle valve opening percentage with full accelartion applied should be 60% or more. but in my car its not more than 25%

http://home.student.utwente.nl/gombe.../SFI/sf-36.pdf

skperformance

iTrader: (6)

it is normal for drive by wire cars as well as yours. Mine opens 60% or so when done by hand the rest is by the electric motor .

PureDrifter

iTrader: (10)

according to my obdii setup at full throttle my absolute throttle position is ~80.2-80.8% open.

skperformance

iTrader: (6)

that is with the engine running it is 80% .
Open it by hand , engine off with the key "on" and watch the reading.

qewani1

am not getting more than 25% at WOT "wide throttle open" i think my low MPG and other LS400 owners maybe mainly due to this, since engine isn't getting enough air with full acceleration. People suggesting change of engine air filter, but if the throttle plate's maximum open percentage is only 25% then we got something else to fix first.
I have googled for this issue. I don't know what could be the problem. any suggestions?

billydpowe

iTrader: (1)

I dont want to mess with mine.. I get 28+ to 30 mpg on the freeway, with AC on. my average is 24.... who is getting bad mileage?

j three

I get about 19-22 mpg per tank according to my dash display.

qewani1

billy if you could use obd2 scanner and read the "absolute throttle position" value with full acceleration applied and report back?
, thanks

GRAND_LS 4

iTrader: (2)

I was thinking what was said above, its an electronic butterfly, so with the engine off, your not going to be able to move it much. Mine was about the same and had to use a rod to open it fully. Does the car "feel" slow?

carfun

Hi can you please let me know what software have you been using ??
Many thanks in advance for your reply.