sayow

So my wife has a 98 LS and reported to me that the car was acting weird when shifting. So I took the car for the entire day and confirmed that it shifts perfectly through all gears when accelerating but if you are say in traffic and slowing down and re-accelerating (typical stop and go traffic) the car will rev slightly (slip?) when going from 1st to 2nd gear.

I can make it happen every time but only in the above scenario. Any ideas or similar experiences and feedback would be appreciated.

brybo86

Any background info?
Trans maintenance , fluid changes? Fluid level?

Were u waiting for someone to ask before telling us?

dicer

In what gears? Its flaring when shifting up. Sticky shift valve, solenoid, low line pressure, dirty screen, old fluid, just some things I can think of. Then theres the ecu stuff. Address what brybo86 says first then let us know how its going. How many miles on it?

Yamae

Believe it or not, it's often caused by the clogged throttle body and the air mix passage. It's not caused by the transmission.

There are many 98-00 owners who suffer that. Search the Forum and you'll find them.
Here's an example.
https://www.clublexus.com/forums/ls-...ml#post8906720

sayow

That is EXACTLY how her LS is behaving! Thank you for the information!!

dicer

So improper signal to ecu from clogged throttle body, I got it covered with the ecu stuff.

sayow

I threw a can of Techron in her for the week to see if that will clear it up. If not I will get into the throttle body this weekend and do some manual work.

alien1974

mine does this too, try putting it in 3 when slowing down or in traffic, that sorted it for me.

Daspyda

iTrader: (1)

Yesterday, I took off the intake plenum assembly and sprayed/wiped down the inside of the throttle body. I then took off the plate just above the TB opening (2 brass screws) and it was CAKED with sludge. I sprayed the area, including down each hole on either side (putting the straw down the hole as far as possible) and then wiped down everything, including the underside of the plate.

I now have a car that works perfectly. Consistent idling and low speed behavior, no more tranny "slippage". My daily drive through the parking garage is much more pleasant.

I even identified a couple of hoses that had become split and is probably affecting MPG.

Thanks, gang!

alien1974

out of interest which hoses are gone, as it could be them causing problems too, mine has the same idle and low speed behavoir, i cleaned my TB and the air pass when i got the car, but to no avail, it only idles properly when the AC is on.

Daspyda

iTrader: (1)

One hose is at the rear of the engine, at the top, and it goes into the air chamber connected to the intake plenum going to the throttle body, located on the left side of the engine,

The other one is on the right side of the air chamber, near the front by the intake air section, The nipple has actually broken off the air chamber, so I am going to try some PVC cement on that.

Scraape

my 98 does this as well.
It seems these 5-speed transmissions up-shift very quickly.
Toyota Type IV tranny fluid is new, new filter as well
I've cleaned my throttle body and air mix path and have seen minimal results so far.

Maybe it has something to do with shift valves & solenoids getting old/going bad?

dicer

Aren't these a gas pedal by wire car? It could be the pedal resister too.

Yamae

The Techron only cleans the fuel passages. It has no capability to clean the air mix passages. Simply do as MngreLMatt has done.

Yamae

Congratulations on your success, Daspyda. The problem is rather common but it seems to me that many people don't know the fact and advices given from them are a bit off from the actual problem.