qha_vn

Hi everyone, i just notice that my car wont allow me to rev the engine more then 2000rpm when it stands still. meaning, when i step on gas pedal and shifter is in P, the engine rev up to 2000rpms and automatically drops back to 650rpm even if my foot is still on pedal depressed. if i try again, engine rev up to 2000 and drops back to idle

If the car is in action (shifter in D) engine easily reaches to 3000 rpm before shifting to another gear when i floor

is that normal for all 1990 LS400? (95k miles on clock)

PK_Celsior

iTrader: (18)

thats weriddd. my 1995 LS400 lets me go to full redline in park. i believe there is somethin wrong there. In drive my car will shift at 3k rpm if im just cruisin and when i mash it full redline. if the owner before you drove slow that might be the reason. i would unplug the battery for 10sec -20sec. put it back on so it can reset the ecm.

PureDrifter

iTrader: (10)

tps issue it sounds like.

lexls has a tut on readjusting it

qha_vn

so what should i would start with? could you please send a link or some more details

thanks

LiCelsior

iTrader: (32)

http://www.lexls.com/tutorials/EFI/tps.html

PK_Celsior

iTrader: (18)

http://www.lexls.com/tutorials/EFI/tps.html
there the TPS readjusting

i would do the battery unplugging first and see what happens . do the easiest things first before the hardest :]

PureDrifter

iTrader: (10)

LiCelsior - 1
PK_Celsior - 0

LiCelsior

iTrader: (32)

w000t . sry pk lol..have fun at the meet.

PK_Celsior

iTrader: (18)

haha its coo. right when i click submit i saw yours come up im like dangit lol

qha_vn

thanks guys, i am still confused why tps (throttle position sensor) may be the cause as it is still working fine when the car is running (reach to 3000rpm before shifting to next gear)

PureDrifter

iTrader: (10)

it may very well NOT be the issue but its easy to check so its one of the first things i would look at.