miller5

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

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.....? <_<

Thx...will order them and post what happens.You guys have been great :D

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......

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....

ok thx...

Got in it to go to lunch and when I put it in reverse it bucked a few times.....Should I buy new sensors, trans fluid before getting another transmission?

Any thoughts on how long before I know if this problem is really fixed? That's a tough question. It all depends on the frequency of the problems you were having and how many cycles you go through problem free before feeling comfortable that it is fixed. Just got in it to goto lunch and when I put it in reverse it started bucking. Is the transmission shot or do I need to get new sensors?

Any thoughts on how long before I know if this problem is really fixed?

Ok thanks for the information...you guys have been great and possibly a lifesaver.....I'll let you know what happens.... ;) Cleaned the MAF sensor and cleaned and switched the speed sensors. The first speed sensor that I took out (the one that is 45 degrees from the battery) had some sludge on it but the other one had the pink transmission fluid on it. Drives great so far-better than when we bought it a couple of years ago. I will keep you posted. If this doesn't fix the problem when will I know? Should I go ahead and get the transmission fluid replaced just to be sure it has the right kind in it? Because the first sensor had sludge on it, does that mean they didn't flush it like they said they did?

Update: Cleaned the MAF sensor and cleaned and switched the speed sensors. The first speed sensor that I took out (the one that is 45 degrees from the battery) had some sludge on it but the other one had the pink transmission fluid on it. Drives great so far-better than when we bought it a couple of years ago. I will keep you posted. If this doesn't fix the problem when will I know? Should I go ahead and get the transmission fluid replaced just to be sure it has the right kind in it? Because the first sensor had sludge on it, does that mean they didn't flush it like they said they did?

Good point about the scanner. What does one run @ $125...?

Ok thanks for the information...you guys have been great and possibly a lifesaver.....I'll let you know what happens.... ;)

Before I take them out should I remove the neg battery cable or does it matter?

Thanks for your advise. I appreciate your input. Where is the speed sensor located? Is there anywhere on this site that shows you where they are located. According to a few posts that I've read, they are easy to get to and clean...

Unfortunately, your friend at the dealership could be correct. HAve you had the transmission flushed regularly before? I see this problem alot. Flushing your trans always sounds like a great idea, but only if you have done it form the beginning and thru out the life of the trans. The issue is the heat from the trans breaks down the fluid, which reacts with the surfaces of all the internal components causing them to tarnish and create sludge. Once this has happened it is better to leave it alone, and just replace the fluid 3-4 quarts at a time from the pan. Because if you remove all the tranish and sludge, what you leave behind are gaps and spaces that cause the transmission to slip and stick. If this starts to happen, the only thing you can do is drive it while you save up for a transmission rebuild or a new transmission. This is ridiculuos! It's up to them to know what the correct fluid is. Alot of car manufacturers have very specific ATF requirements. If they are unaware of them, then they are not qualified to be performing transmission flushes! He was giving you the " I'm an idiot, heres some BS, now go away." line! If they didn't replace the fluid with the correct one, then you very could have a case for the issues your having. According to them it wouldn't have taken this long for the problem to show up if it was a flush problem. I have read other posts here that mimick my problem and the advise was to clean the speed sensors and put them back on or possibly the knock sensor....any thoughts? :( We are the 2nd owners of this car and the only time the transmission was done was a drop and fill.....

Unfortunately, your friend at the dealership could be correct. HAve you had the transmission flushed regularly before? I see this problem alot. Flushing your trans always sounds like a great idea, but only if you have done it form the beginning and thru out the life of the trans. The issue is the heat from the trans breaks down the fluid, which reacts with the surfaces of all the internal components causing them to tarnish and create sludge. Once this has happened it is better to leave it alone, and just replace the fluid 3-4 quarts at a time from the pan. Because if you remove all the tranish and sludge, what you leave behind are gaps and spaces that cause the transmission to slip and stick. If this starts to happen, the only thing you can do is drive it while you save up for a transmission rebuild or a new transmission. This is ridiculuos! It's up to them to know what the correct fluid is. Alot of car manufacturers have very specific ATF requirements. If they are unaware of them, then they are not qualified to be performing transmission flushes! He was giving you the " I'm an idiot, heres some BS, now go away." line! If they didn't replace the fluid with the correct one, then you very could have a case for the issues your having. According to them it wouldn't have taken this long for the problem to show up if it was a flush problem. I have read other posts here that mimick my problem and the advise was to clean the speed sensors and put them back on or possibly the knock sensor....any thoughts? :(

I am kind of new to this forum (one other post last year) and am not quite sure how to post these things so bear with me My wife has a 200 RX 300 and a few months ago it wouldn't go into reverse either. It did it a few times with her and then stopped. I went and had the transmission flushed (not at a dealer) with the assurance and promise from the service tech that I wouldn't have any transmission problems because of the flush. This was done Back in May. A few days ago I noticed that it would shift hard between 1st and 2nd gear before the engine got warmed up. After the engine warms up it shifts fine. Then yesterday it slipped slightly (again when cold). The check engine light also came on for @ 5 minutes then it went off (wasn't flashing). I have a mechanic friend who works at the Toyota dealership as a technician and he said that the flush probably is the culprit and the tranmission is probably going bad because of the flush. The car has 130k on it and has never given us any problems until now. Could it be: -the knock sensor -speed sensors -that they didin't put the type IV fluid in it that is required? I called them to see if they put it in Lexus' when they flush them and the man said "they can.....but they need a heads up before the work is done so they can get the fluid in"...... HELP...... :(

I am kind of new to this forum (one other post last year) and am not quite sure how to post these things so bear with me My wife has a 200 RX 300 and a few months ago it wouldn't go into reverse either. It did it a few times with her and then stopped. I went and had the transmission flushed (not at a dealer) with the assurance and promise from the service tech that I wouldn't have any transmission problems because of the flush. This was done Back in May. A few days ago I noticed that it would shift hard between 1st and 2nd gear before the engine got warmed up. After the engine warms up it shifts fine. Then yesterday it slipped slightly (again when cold). The check engine light also came on for @ 5 minutes then it went off (wasn't flashing). I have a mechanic friend who works at the Toyota dealership as a technician and he said that the flush probably is the culprit and the tranmission is probably going bad because of the flush. The car has 130k on it and has never given us any problems until now. Could it be: -the knock sensor -speed sensors -that they didin't put the type IV fluid in it that is required? I called them to see if they put it in Lexus' when they flush them and the man said "they can.....but they need a heads up before the work is done so they can get the fluid in"...... HELP......

I am new to this forum and am not quite sure how to post these things so bear with me ;) My wife has a 200 RX 300 and a few months ago it wouldn't go into reverse either. It did it a few times with her and then stopped. I went and had the transmission flushed (not at a dealer) with the assurance and promise from the service tech that I wouldn't have any transmission problems because of the flush. This was done Back in May. A few days ago I noticed that it would shift hard between 1st and 2nd gear before the engine got warmed up. After the engine warms up it shifts fine. Then yesterday it slipped slightly (again when cold). The check engine light also came on for @ 5 minutes then it went off (wasn't flashing). I have a mechanic friend who works at the Toyota dealership as a technician and he said that the flush probably is the culprit and the tranmission is probably going bad because of the flush. The car has 130k on it and has never given us any problems until now. Could it be: -the knock sensor -speed sensors -that they didin't put the type IV fluid in it that is required? I called them to see if they put it in Lexus' when they flush them and the man said "they can.....but they need a heads up before the work is done so they can get the fluid in"...... HELP......

It was definitely easy to do! Unfortunately we are still having the 2nd/3rd problem, but it's not as bad and we're going to order the replacements tomorrow and get them put in ASAP. Thanks again to all who responded and helped us! What replacements did you order and how is the car running now?

get a new mechanic Yes this is great advice... <_< I swear, if everyone fired their mechanic every time they made a mistake, there would be alot of unemployed mechanics out there... Its quality posts like this one that turn people away from us for help. if you dont have any valuable advice, please allow those who know what they are doing to help and assist those who dont. FWIW the valve seals were 95% of the problem, the PCV valve is the other 5%. change it. its causing oil blow by past your rings as suggested earlier. it costs like $4 for the part and a half hour of labor. enjoy! Thanks for the post. It looks like your diagnosis was right on. PCV valve was replaced and after 2 days the smoke has cleared hallelujah!

get a new mechanic Yes this is great advice... <_< I swear, if everyone fired their mechanic every time they made a mistake, there would be alot of unemployed mechanics out there... Its quality posts like this one that turn people away from us for help. if you dont have any valuable advice, please allow those who know what they are doing to help and assist those who dont. FWIW the valve seals were 95% of the problem, the PCV valve is the other 5%. change it. its causing oil blow by past your rings as suggested earlier. it costs like $4 for the part and a half hour of labor. enjoy!

I have a 1996 ES300 and I just had the valve seals replaced because it would smoke when it started-especially when it was parked on a hill. The problem is it is still smoking although not as much. My mechanic said that he didn't know what else could be causing this. Any ideas?