I have an odd problem with my 1991 LS400 (101K miles). My car used to have terrific acceleration upon full throttle, the transmission would kick in and the car would take off like a rocket.
Just recently, I noticed when I depress the throttle fully, the car doesn't kick down and I get almost no acceleration or slow acceleration. The car kind of surges but goes nowhere. My engine rpms go up to 5000, but I'm hardly moving. The kicker is, the car runs fine on normal driving (street and mostly freeway) just seems to have a problem with full throttle kickdown.
It's weird, it appears maybe the tranny is acting up? But the car drives fine normally. Any help would be appreciated, Thanks in advance.