Rx #00 Transmission Problem?

[smooth1]

I really don't think the scan tool is going to help here without getting a check engine light. The sensors in the RX act up and send out bad readings causing trans problems like the reverse issue. Problem is the ECM is not recognizimng sensor failure and does not generate a code. I know there are OBDII codes for the sensor, that you will get if the sensor flat out fails, but that is not the case.

That's why I recommended one that has Freeze Frame. The ECU is not a warning system. It logs data and applies the correct programmed logic to the information it has acquired. Just as an example, take a knock sensor. If it logs a knock event, it will log that in the ECU,but no cel will come up yet. If the knock occurs X amount of times in any given period of time, it will !Removed! or advance the ignition as required. But if the knock continues even beyond that it will trigger the cel to go off. But if the sensor stops working, then the cel will come up as the resistance meter will be outside it's parameters and read as a failed sensor. But the events are still there to look at and see what has been going on. The lack of a cel is what I was looking at here. which is why I recommended switching the sensors back to thier original position, clean them off again while your doing that and see if the problem still exsists. If so, maybe the sensor is reading a real problem, but the events haven't happened enouph times to trigger the cel as it's reverse now, (how long are you in reverse for?) Once we can determine the sensor is good or bad, then we can move on to other contributing factors. Yes or no?

[miller5]

I would check those snesors again first. Maybe pull em and see if they need cleaning again, then switch them back. Maybe consider doing this a few times to make sure it's not the problem before moving on. You may need to replace the sensors. It's hard to say with out the ODB II scan to tell us whats going on.

ok thx...

I really don't think the scan tool is going to help here without getting a check engine light. The sensors in the RX act up and send out bad readings causing trans problems like the reverse issue. Problem is the ECM is not recognizimng sensor failure and does not generate a code. I know there are OBDII codes for the sensor, that you will get if the sensor flat out fails, but that is not the case.

I am sure you have the sensors clean, because I have done this before and there is not much to it. Just wipe it off. The big question here is: Does the RX react differently when the sensors are swapped?. You may want to swap again to verify this. I would expect you to have the reverse issue when they are in one position and some kind of foward shifting issue when they are in the other position. If this is the case one of the sensors must be bad. I would just replace them both. If you are going to do this you have to verify which ones you have. They are either Aisin Seiki or Toyota. The Aisin Seiki are labeled Aisin Seiki on one side of the sensor and Toyota on the other side. I am not sure how the Toyota ones are labeled, most likely Toyota on both sides. You can get them from rockauto.com for about $70/each. They are under cruise control sensors.

I don't really suspect the fluid unless they didn't use a compatible fluid. If that's the case you could do another flush to get all the fluid out and replace with Toyota type T-IV.

If it were me lastly I would drop the trans pan to make sure the trans filter isn't plugged. This shouldn't be the case as the factory filter is a free flowing screen. Unless someone changed it to a paper filter when they serviced the trans previously.

Before the sensors were swapped the transmission would shift hard between 1st and 2nd. After the sensors were switched the car has run like a dream until the reverse issue today....

[miller5]

I really don't think the scan tool is going to help here without getting a check engine light. The sensors in the RX act up and send out bad readings causing trans problems like the reverse issue. Problem is the ECM is not recognizimng sensor failure and does not generate a code. I know there are OBDII codes for the sensor, that you will get if the sensor flat out fails, but that is not the case.

That's why I recommended one that has Freeze Frame. The ECU is not a warning system. It logs data and applies the correct programmed logic to the information it has acquired. Just as an example, take a knock sensor. If it logs a knock event, it will log that in the ECU,but no cel will come up yet. If the knock occurs X amount of times in any given period of time, it will !Removed! or advance the ignition as required. But if the knock continues even beyond that it will trigger the cel to go off. But if the sensor stops working, then the cel will come up as the resistance meter will be outside it's parameters and read as a failed sensor. But the events are still there to look at and see what has been going on. The lack of a cel is what I was looking at here. which is why I recommended switching the sensors back to thier original position, clean them off again while your doing that and see if the problem still exsists. If so, maybe the sensor is reading a real problem, but the events haven't happened enouph times to trigger the cel as it's reverse now, (how long are you in reverse for?) Once we can determine the sensor is good or bad, then we can move on to other contributing factors. Yes or no?

We only got a check engine light for @ 5 minutes before, when the sensors were in the original position, then it went away. We were in reverse just long enough to back out of a parking spot-still no engine light then. I had to back out when I left work and reverse worked fine......

[smooth1]

Transmissions are a world all to themselves. ASE certified mechanics aren't even qualified to work on them. You may need a transmission specialist to sort out this. But first, I would just swap the sensors, clean em again when you do. If the problem persists, or switches back to 1st and 2nd, then it very well could be one of the sensors. But then it's figuring out which one. YOu could just replace both, or you could try and find out which on it is, and just replace that one. If you replace them both, and still have this issue, then it's really time for you to take it in and have the tranny pros tell you how much it will cost.

[mikey00]

"Before the sensors were swapped the transmission would shift hard between 1st and 2nd. After the sensors were switched the car has run like a dream until the reverse issue today...."

That certainly makes it look like a sensor issue. I would get 2 new ones. The RX used 2 different types of sensors with a slightly different connection. Make sure you read my post about getting the right ones so they fit the connector in your RX. Rock Auto is the cheapest at about $70 ea. The Lexus dealer will get $90. + for them.

[miller5]

"Before the sensors were swapped the transmission would shift hard between 1st and 2nd. After the sensors were switched the car has run like a dream until the reverse issue today...."

That certainly makes it look like a sensor issue. I would get 2 new ones. The RX used 2 different types of sensors with a slightly different connection. Make sure you read my post about getting the right ones so they fit the connector in your RX. Rock Auto is the cheapest at about $70 ea. The Lexus dealer will get $90. + for them.

Thx...will order them and post what happens.

You guys have been great :D

[miller5]

"Before the sensors were swapped the transmission would shift hard between 1st and 2nd. After the sensors were switched the car has run like a dream until the reverse issue today...."

That certainly makes it look like a sensor issue. I would get 2 new ones. The RX used 2 different types of sensors with a slightly different connection. Make sure you read my post about getting the right ones so they fit the connector in your RX. Rock Auto is the cheapest at about $70 ea. The Lexus dealer will get $90. + for them.

Thx...will order them and post what happens.

You guys have been great :D

What makes them go bad? How do they go bad? Do they lose their magnetic pull.....? <_<

[mikey00]

"Before the sensors were swapped the transmission would shift hard between 1st and 2nd. After the sensors were switched the car has run like a dream until the reverse issue today...."

That certainly makes it look like a sensor issue. I would get 2 new ones. The RX used 2 different types of sensors with a slightly different connection. Make sure you read my post about getting the right ones so they fit the connector in your RX. Rock Auto is the cheapest at about $70 ea. The Lexus dealer will get $90. + for them.

Thx...will order them and post what happens.

You guys have been great :D

What makes them go bad? How do they go bad? Do they lose their magnetic pull.....? <_<

Not sure. I was lucky, I just cleaned mine and swapped their positions and the problem never returned.

[miller5]

"Before the sensors were swapped the transmission would shift hard between 1st and 2nd. After the sensors were switched the car has run like a dream until the reverse issue today...."

That certainly makes it look like a sensor issue. I would get 2 new ones. The RX used 2 different types of sensors with a slightly different connection. Make sure you read my post about getting the right ones so they fit the connector in your RX. Rock Auto is the cheapest at about $70 ea. The Lexus dealer will get $90. + for them.

Thx...will order them and post what happens.

You guys have been great :D

What makes them go bad? How do they go bad? Do they lose their magnetic pull.....? <_<

Not sure. I was lucky, I just cleaned mine and swapped their positions and the problem never returned.

Put the new ones in last night and everything seems fine so far-just like last time. You said in an earlier post that you wouldn't take it to get flushed/filled again. Is there an additive that you would recommend? A friend of mine has an LS 400 and he was having some shifting problems and he found a tube of stuff that used to only be available at the dealer but now is found at the parts stores. He couldn't remember what it was called. Do you know and if so, would I need it just to cover my bases?

Thx

[miller5]

"Before the sensors were swapped the transmission would shift hard between 1st and 2nd. After the sensors were switched the car has run like a dream until the reverse issue today...."

That certainly makes it look like a sensor issue. I would get 2 new ones. The RX used 2 different types of sensors with a slightly different connection. Make sure you read my post about getting the right ones so they fit the connector in your RX. Rock Auto is the cheapest at about $70 ea. The Lexus dealer will get $90. + for them.

Thx...will order them and post what happens.

You guys have been great :D

What makes them go bad? How do they go bad? Do they lose their magnetic pull.....? <_<

Not sure. I was lucky, I just cleaned mine and swapped their positions and the problem never returned.

Put the new ones in last night and everything seems fine so far-just like last time. You said in an earlier post that you wouldn't take it to get flushed/filled again. Is there an additive that you would recommend? A friend of mine has an LS 400 and he was having some shifting problems and he found a tube of stuff that used to only be available at the dealer but now is found at the parts stores. He couldn't remember what it was called. Do you know and if so, would I need it just to cover my bases?

Thx

CEL came on at lunch and I took it to Advanced Auto to get a reading and the code was P1130....? Very low on fuel. Could that be the cause?

[smooth1]

??? How is the car driving? is it a shifting problem, or a hesitation, stutter, stumble problem? I was under the impression the car wouldn't shift or had hard shifting issues. I don't understand how we went from a transmission issue to an 02 issue.

[miller5]

??? How is the car driving? is it a shifting problem, or a hesitation, stutter, stumble problem? I was under the impression the car wouldn't shift or had hard shifting issues. I don't understand how we went from a transmission issue to an 02 issue.

It's driving good and smooth.....

[miller5]

??? How is the car driving? is it a shifting problem, or a hesitation, stutter, stumble problem? I was under the impression the car wouldn't shift or had hard shifting issues. I don't understand how we went from a transmission issue to an 02 issue.

It's driving good and smooth.....

is it an o2 issue or an a/f sensor..?

[miller5]

??? How is the car driving? is it a shifting problem, or a hesitation, stutter, stumble problem? I was under the impression the car wouldn't shift or had hard shifting issues. I don't understand how we went from a transmission issue to an 02 issue.

It's driving good and smooth.....

is it an o2 issue or an a/f sensor..?

It did have shifting issues...hard between 1st and 2nd(before the sensor switching) and reverse problem (after sensor switch)....

[mikey00]

I thought we had 2 seperate issues here right from the beginning. First is the reverse and foward shifting issue. It sounds like you may have this fixed with the new sensors, which only time will tell. If the trans problem is fixed, I wouldn't go looking for a tube of some sort of trans conditioner. Also, I don't think the sky is falling just because they used a compatible transmission fluid rather than genuine Toyota type T-IV. If it were me, I would get some life out of the fluid and then go back to Toyota type T-IV in the future with a flush or multiple drain and fills.

Second is the check engine light which went out on it's own and we thought may have been fixed with you cleaning the maf. But the CEL is back now. A P1130 is a Air Fuel Ratio sensor (bank 1 sensor 1). Here is a link to a previous discussion on the sensor complete with a pic of its location and a source for the part.

http://www.clublexus.com/forums/showthread.php?t=364261

[miller5]

I thought we had 2 seperate issues here right from the beginning. First is the reverse and foward shifting issue. It sounds like you may have this fixed with the new sensors, which only time will tell. If the trans problem is fixed, I wouldn't go looking for a tube of some sort of trans conditioner. Also, I don't think the sky is falling just because they used a compatible transmission fluid rather than genuine Toyota type T-IV. If it were me, I would get some life out of the fluid and then go back to Toyota type T-IV in the future with a flush or multiple drain and fills.

Second is the check engine light which went out on it's own and we thought may have been fixed with you cleaning the maf. But the CEL is back now. A P1130 is a Air Fuel Ratio sensor (bank 1 sensor 1). Here is a link to a previous discussion on the sensor complete with a pic of its location and a source for the part.

http://www.clublexus.com/forums/showthread.php?t=364261

I saw from another post somewhere that the RX 300 couldn't use anything but the Toyota Type T-IV fluid or it would cause the transmission to go bad.

The light hasn't come back on since I left work.....do you think it was a hiccup or something I should go ahead and do? What does this sensor do anyway?

Thx for all your expertise B)

[mikey00]

To oversimplify it, the air fuel ratio sensor measures the engines exhaust output and sends a signal back to the ECU to vary the air/fuel mixture the engine receives. It is part of the emmissions system. You can google it if you want to get into it a little more. As long as your CEL went off, I would wait to make sure it is a valid problem before changing the sensor.

To answer your question about the fluid. I realize there are people out there that say the sky will fall if you don't use Toyota Type T-IV. Others swear by some compatibles that claim to exceed manufactures specs such as Amsoil fluid. I prefer to use the Toyota fluid but as long as the shop used a compatible fluid you should be fine. If it were me, I would get my moneys worth out of the present fluid and change back to Toyota when it's time. If it gives you piece of mind change back sooner.

Make sure you post back and let us know if the sensors fixed the trans problem after you take some time to test. I hate to think of all the 5k transmission swaps Lexus did that could have been fixed by sensors.

[miller5]

To oversimplify it, the air fuel ratio sensor measures the engines exhaust output and sends a signal back to the ECU to vary the air/fuel mixture the engine receives. It is part of the emmissions system. You can google it if you want to get into it a little more. As long as your CEL went off, I would wait to make sure it is a valid problem before changing the sensor.

To answer your question about the fluid. I realize there are people out there that say the sky will fall if you don't use Toyota Type T-IV. Others swear by some compatibles that claim to exceed manufactures specs such as Amsoil fluid. I prefer to use the Toyota fluid but as long as the shop used a compatible fluid you should be fine. If it were me, I would get my moneys worth out of the present fluid and change back to Toyota when it's time. If it gives you piece of mind change back sooner.

Make sure you post back and let us know if the sensors fixed the trans problem after you take some time to test. I hate to think of all the 5k transmission swaps Lexus did that could have been fixed by sensors.

I put the new sensors on last Sunday a week ago and no problems until tonight. Again, it has driven better than ever until I put it in reverse when I was coming home tonight. When I was backing up it started lunging a little. I got the sensors from a local parts store. Did that come back to bite me....?

[mikey00]

To oversimplify it, the air fuel ratio sensor measures the engines exhaust output and sends a signal back to the ECU to vary the air/fuel mixture the engine receives. It is part of the emmissions system. You can google it if you want to get into it a little more. As long as your CEL went off, I would wait to make sure it is a valid problem before changing the sensor.

To answer your question about the fluid. I realize there are people out there that say the sky will fall if you don't use Toyota Type T-IV. Others swear by some compatibles that claim to exceed manufactures specs such as Amsoil fluid. I prefer to use the Toyota fluid but as long as the shop used a compatible fluid you should be fine. If it were me, I would get my moneys worth out of the present fluid and change back to Toyota when it's time. If it gives you piece of mind change back sooner.

Make sure you post back and let us know if the sensors fixed the trans problem after you take some time to test. I hate to think of all the 5k transmission swaps Lexus did that could have been fixed by sensors.

I put the new sensors on last Sunday a week ago and no problems until tonight. Again, it has driven better than ever until I put it in reverse when I was coming home tonight. When I was backing up it started lunging a little. I got the sensors from a local parts store. Did that come back to bite me....?

Sensors from a local parts store most likely come from the same manufacturer, so I wouldn't expect a problem with them. Maybe it's time to try a flush or a couple of drain and fills in succession to remove the "compatible"?? fluid.

[miller5]

To oversimplify it, the air fuel ratio sensor measures the engines exhaust output and sends a signal back to the ECU to vary the air/fuel mixture the engine receives. It is part of the emmissions system. You can google it if you want to get into it a little more. As long as your CEL went off, I would wait to make sure it is a valid problem before changing the sensor.

To answer your question about the fluid. I realize there are people out there that say the sky will fall if you don't use Toyota Type T-IV. Others swear by some compatibles that claim to exceed manufactures specs such as Amsoil fluid. I prefer to use the Toyota fluid but as long as the shop used a compatible fluid you should be fine. If it were me, I would get my moneys worth out of the present fluid and change back to Toyota when it's time. If it gives you piece of mind change back sooner.

Make sure you post back and let us know if the sensors fixed the trans problem after you take some time to test. I hate to think of all the 5k transmission swaps Lexus did that could have been fixed by sensors.

I put the new sensors on last Sunday a week ago and no problems until tonight. Again, it has driven better than ever until I put it in reverse when I was coming home tonight. When I was backing up it started lunging a little. I got the sensors from a local parts store. Did that come back to bite me....?

Sensors from a local parts store most likely come from the same manufacturer, so I wouldn't expect a problem with them. Maybe it's time to try a flush or a couple of drain and fills in succession to remove the "compatible"?? fluid.

If I go the drain and fill route should I do one each day,every few days or every few weeks? Are there directions on this site for that?

[lenore]

To oversimplify it, the air fuel ratio sensor measures the engines exhaust output and sends a signal back to the ECU to vary the air/fuel mixture the engine receives. It is part of the emmissions system. You can google it if you want to get into it a little more. As long as your CEL went off, I would wait to make sure it is a valid problem before changing the sensor.

To answer your question about the fluid. I realize there are people out there that say the sky will fall if you don't use Toyota Type T-IV. Others swear by some compatibles that claim to exceed manufactures specs such as Amsoil fluid. I prefer to use the Toyota fluid but as long as the shop used a compatible fluid you should be fine. If it were me, I would get my moneys worth out of the present fluid and change back to Toyota when it's time. If it gives you piece of mind change back sooner.

Make sure you post back and let us know if the sensors fixed the trans problem after you take some time to test. I hate to think of all the 5k transmission swaps Lexus did that could have been fixed by sensors.

I put the new sensors on last Sunday a week ago and no problems until tonight. Again, it has driven better than ever until I put it in reverse when I was coming home tonight. When I was backing up it started lunging a little. I got the sensors from a local parts store. Did that come back to bite me....?

Sensors from a local parts store most likely come from the same manufacturer, so I wouldn't expect a problem with them. Maybe it's time to try a flush or a couple of drain and fills in succession to remove the "compatible"?? fluid.

If I go the drain and fill route should I do one each day,every few days or every few weeks? Are there directions on this site for that?

Here it is:

http://www.clublexus.com/forums/showthread.php?t=220061

[miller5]

To oversimplify it, the air fuel ratio sensor measures the engines exhaust output and sends a signal back to the ECU to vary the air/fuel mixture the engine receives. It is part of the emmissions system. You can google it if you want to get into it a little more. As long as your CEL went off, I would wait to make sure it is a valid problem before changing the sensor.

To answer your question about the fluid. I realize there are people out there that say the sky will fall if you don't use Toyota Type T-IV. Others swear by some compatibles that claim to exceed manufactures specs such as Amsoil fluid. I prefer to use the Toyota fluid but as long as the shop used a compatible fluid you should be fine. If it were me, I would get my moneys worth out of the present fluid and change back to Toyota when it's time. If it gives you piece of mind change back sooner.

Make sure you post back and let us know if the sensors fixed the trans problem after you take some time to test. I hate to think of all the 5k transmission swaps Lexus did that could have been fixed by sensors.

I put the new sensors on last Sunday a week ago and no problems until tonight. Again, it has driven better than ever until I put it in reverse when I was coming home tonight. When I was backing up it started lunging a little. I got the sensors from a local parts store. Did that come back to bite me....?

Sensors from a local parts store most likely come from the same manufacturer, so I wouldn't expect a problem with them. Maybe it's time to try a flush or a couple of drain and fills in succession to remove the "compatible"?? fluid.

If I go the drain and fill route should I do one each day,every few days or every few weeks? Are there directions on this site for that?

Here it is:

http://www.clublexus.com/forums/showthread.php?t=220061

Couple of questions: How often? What fluid would you recommend? Is there a problem with cross catamination of fluids? How long should it take to do?

[mikey00]

I would use Toyota Type T-IV which is exactly what belongs in there. Others could be better or could be worse but why deal with an unknown when you are trying to get your tranny back to normal. Some where around $4.75 per quart at Toyota dealer. You should use about 4.5 qts. per drain and fill.

Assuming you are just doing a drain and fill using the 2 drain plugs mentioned in the link, it should take about 30 minutes. If you drop the pan and change the filter add at least 40 minutes.

Remember a drain and fill is only going to get 50% of the total fluid out. So you are going to have some mixing of the old and new. Next drain and fill will get some more old out along with some new. So after 2 drain and fills you will have about 75/25 mix of new to old. You will get a diminishing return on each drain and fill. 2 or 3 drain and fills should be enough. Or you could just get a flush which will replace all the fluid at once but will cost more.

There is also a procedure around to disconnect one of the trans cooler lines and run the car to pump out the old fluid as you pour in new to replace all the fluid at once.

[miller5]

I would use Toyota Type T-IV which is exactly what belongs in there. Others could be better or could be worse but why deal with an unknown when you are trying to get your tranny back to normal. Some where around $4.75 per quart at Toyota dealer. You should use about 4.5 qts. per drain and fill.

Assuming you are just doing a drain and fill using the 2 drain plugs mentioned in the link, it should take about 30 minutes. If you drop the pan and change the filter add at least 40 minutes.

Remember a drain and fill is only going to get 50% of the total fluid out. So you are going to have some mixing of the old and new. Next drain and fill will get some more old out along with some new. So after 2 drain and fills you will have about 75/25 mix of new to old. You will get a diminishing return on each drain and fill. 2 or 3 drain and fills should be enough. Or you could just get a flush which will replace all the fluid at once but will cost more.

There is also a procedure around to disconnect one of the trans cooler lines and run the car to pump out the old fluid as you pour in new to replace all the fluid at once.

Did 3 drain and fills and it was running fine until today. When cold (1st thing in the morning) the transmission is shifting hard btwn 1st and 2nd slipping btwn 2nd and 3rd......is it gone?

[miller5]

I would use Toyota Type T-IV which is exactly what belongs in there. Others could be better or could be worse but why deal with an unknown when you are trying to get your tranny back to normal. Some where around $4.75 per quart at Toyota dealer. You should use about 4.5 qts. per drain and fill.

Assuming you are just doing a drain and fill using the 2 drain plugs mentioned in the link, it should take about 30 minutes. If you drop the pan and change the filter add at least 40 minutes.

Remember a drain and fill is only going to get 50% of the total fluid out. So you are going to have some mixing of the old and new. Next drain and fill will get some more old out along with some new. So after 2 drain and fills you will have about 75/25 mix of new to old. You will get a diminishing return on each drain and fill. 2 or 3 drain and fills should be enough. Or you could just get a flush which will replace all the fluid at once but will cost more.

There is also a procedure around to disconnect one of the trans cooler lines and run the car to pump out the old fluid as you pour in new to replace all the fluid at once.

Did 3 drain and fills and it was running fine until today. When cold (1st thing in the morning) the transmission is shifting hard btwn 1st and 2nd slipping btwn 2nd and 3rd......is it gone?

Dropped the pan and cleaned the filter. It had alot of sludge on it with fine shavings in bottom of pan. Sludge was all over the 3 magnets. Cleaned pan and filter and took it for a test drive around the block and it drove good. Where is the sludge coming from and what is it?