Hello,

I recently both 1999 rx300. It had engine check light on which said it has bad "Knock Sensors". Because of that it was taking too much gas about (22L / 100 KM) in city. Yesterday I got the knock sensors changed and I have noticed the fuel consumption has gone down (13L / 100 KM) and the knock sensor code is gone too. But now I see a new code which says there is some issue with "Shift Solenoid". When I start my car now, initially it doesn't seem to shift gear properly, when i hit accelerator the engine seems to make lots of noise but car doesn't move much. Once I go into 40-50 KM / hour range it seem to work fine and shifts gear properly. It's just on initial stage (even reversing) it doesn't seem to shift the gears. This problem was not there before changing knock sensors.

Does anyone has experienced anything like this? or any idea what the problem could be? I would really appreciate the help.

 

It may be totally unrelated to having the knock sensors replaced. Reset the ECU by disconnecting the battery for an hour. Also, change the transmission fluid.

If a shift solenoid is bad....... that's not good.

 

So after taking it to mechanic I came to know that it's actually not shift solenoid, it's the computer that's has been damaged. They are going to replace the computer today (they found a used one at junk yard) and than take it to Lexus to reprogram the key. Let's hope this would work.

 

That sounds weird, why would the computer go bad? I hope it works out for you.

 

My mechanic told me that the other mechanic who changed the Knock Sensors has actually damaged the computer wiring and then he messed up computer while trying to fix the previous issue. He didn't know about electrical problems so he messed up everything and drove for 1 day and computer went away. Now after installing new computer they are saying it should work fine. My old key is not working with this new computer so I have to take car to Lexus to re-program. That's what my Mechanic is saying, does it make sense?

 

Any update?