bchehab

Hi Guys.

I have the 1999 RX300 AWD. Recently the car started to act strange in gear shifting. Every time the gear shifts it hesitates for 3 or 4 times before going to the next gear and in case the hesitation is minimal I feel some delay in shifting. The hesitation occurs especially from gear 1 to 2 and 2 to 3, or even downshifting. no hesitation from 3rd gear to the 4th or downshifting from 4th to 3rd.
I also noticed that if I am at full stop and I shift to reverse, there is about 1 or 2 seconds of delay then the gear hesitates for 3 or 4 times before the reverse gear takes place. within those 2 seconds delay, I can hear a very low sound of whining.
Another issue I noticed also that started to happen at the same time, every time I start the car, the rpm does not idle correctly, it idles for around 1 second between 750 and 1000 rpm then drops and even sometimes the car switches off and I have to start it again.

I am afraid the transmission is starting to die.
I really appreciate any information or clues to what is happening.


Regards
Bassem

Lexmex

I'd have to ask first when the last time the transmission fluid was checked and replaced including the filter.

bchehab

Thank you Lexmex for your reply.
Actually the last time I changed the fluid and the filter was last may, but since last august, I traveled to Nigeria and the car was rarely driven by my wife. and I came back 2 moths ago.
Early morning today I took it to the mechanic to change the transmission fluid and the filter, and I was surprised to see that the oil is completely burned out with a very bad smell. According to the man, this is a really bad sign that the transmission life is coming to an end.

hypervish

If that was the case, i suggest draining and filling the transmission atleast another 2 times preferably 3 to get the most amount of burnt fluid out and maybe save the transmission from failure.

Burnt fluid doesn't necessarily mean transmission failure, but heat is the number one cause of transmission failure in any car.

thomas1

As for your idle problem the Idle Air Control Valve may need cleaning....Do a search..

bchehab

Thank you hypervish and thomas.

Today I did another drain and fill, and probably I will do another one in the coming few days. I also removed the battery for 15 minutes then I drove the care uphill, and I noticed that the hesitation and the jumping while shifting is stronger when driving up.
What I forgot to mention is that my a/f sensors need to be replaced. but I am not sure if bad a/f sensors can result in such behavior.


regards.

hypervish

The a/f sensor should't be causing this type of behavior. Try driving more aggressively since you have disconnected the battery, and see if that helps.

What type of ATF did you use this time? Toyota type-iv?

I have a feeling the delay with shifting and hesitation has to do with the IACV and the throttle body being dirty.

kidlex93

Seems like what happened to me a couple of months ago. I had my CEL's on and all of a sudden while driving it would jerk while shifting gears. I dont remember which gears but I do remember it was very violent shifting up and down. Also a couple of times I would start my car and it would just die just like yours. I had to replace a couple of sensors (apparently the sensors caused me to have 9+ codes on the OBD scanner). Or maybe I'm just completely off and its your tranny . Good luck and lets hope its not :]

bchehab

Hi Kidlex93,

what censors did you change ?

kidlex93

All I know is that one of them was the o2 sensor but he said he replaced 2 or 3 of them (i dont remember :[ ) sorry i cant of any more help. If it helps he said my car was misfiring, it would change gears roughly, would die after i started the car, and the CEL would blink when I turned the heat on for a while but stop when I turned the heat off and restarted the car. However I dont know about your burnt oil so I hope I'm not leading you down the wrong path :]

Lexmex

That flashing CEL is often a misfire, but there is also a flashing light on the air conditioning panel that can occur after the a/c is turned on. The most common issue with this is that the accessory belt in the engine compartment is wet (and thus slips) and will cause this light.

bowen.chau

Hi bchehab,

Did you find out what cause the problem?
I have the same problem as you now. Lexmex, do you recommend to take out the EFI fuse for 5 minutes first?

Lexmex

The EFI fuse for about 1 minute should be sufficient, the other route is to leave the battery cables off for the same amount of time.

bowen.chau

Hi Lexmex,

I have just tried to take out the EFI fuse and waited for 5 minutes yesterday. And then I have tried to drive it very gently. The transmission seems working fine. However, I am afraid the problem will come out again.

I have just changed my transmission oil last last Friday when I first spotted the problem. By the way, is there any problem if my mechanic over-filled my transmission oil? What will the problems be?

Lexmex

For years my transmission has been overfilled on the stick. Not something I would recommend, but I have had no issues with it.