Rx 300- 2wd 2000model Po171 Then Po330 Obd2 And Transmission Not Going

[smgchandler]

my wifes car has 140,000 miles on it and its paid for so i have to try to fix it myself before taking it elsewhere - tried to trade it before all this happened for a civic and they hurt my feelings so we have decided to drive it until the wheels fall off but im afraid that may be soon if i cant fix it - i have read other topics on this problem but have not solved it yet - OK it started out by check engine light coming on - this was the 171 code so i bought a O2 sensor - naturally it was for the one just before the catalytic converter and not the one on the exhaust manifold - so i got the wrong one - anyhow i didnt put it on yet - then the transmission wouldnt go into od and i knew it was low - after this i drained all the transmission fluid twice and refilled with the correct t-4 fluid - reset the light and it did fine for about 20 miles - then light came back on and it wouldnt go into 3 or maybe OD - it was taching about 3000 on interstate - anyhow i tried cleaning the maf or map sensor just behind the air cleaner with the spray cleaner and that did work for about another 20 miles then light came back on - dont know where to go from here - the transmission shifts and sounds acts fine until light comes on and you get out on the road -the fluid was dark but no pieces or hunks on the plug or in the fluid - i have not changed the O2 sensor yet so that may be the problem and causing the transmission not to shift - i do believe however that the transmission was low before all this started because it does have a small leak but i never checked it until the car wouldnt pull itself in the driveway - then i checked it and it was low - i got the right fluid put in it and it did fine then - anyhow this is where im at now - anyone have any suggestions before i take it to a real mechanic ??? thank you for any help here

[mikey00]

It is important that you keep an eye on the trans fluid and do drain and fills to keep the fluid clean but that is not the problem here. With certain CELs the ECU does not allow the trans to shift into overdrive and that is what is happening here. In most cases cleaning the MAF fixes this code. Another common cause on 2000 and older RXs is the exhaust flex piece after the exhaust manifold leaking. You may also want to check out obd-codes.com for some other ideas.

The P0330 is usually a knock sensor. I would clean or replace the MAF to fix P0171 and hope it also clears the knock sensor code. If not you may to check here:

http://us.lexusownersclub.com/forums/index...sor+replacement

[smgchandler]

It is important that you keep an eye on the trans fluid and do drain and fills to keep the fluid clean but that is not the problem here. With certain CELs the ECU does not allow the trans to shift into overdrive and that is what is happening here. In most cases cleaning the MAF fixes this code. Another common cause on 2000 and older RXs is the exhaust flex piece after the exhaust manifold leaking. You may also want to check out obd-codes.com for some other ideas.

The P0330 is usually a knock sensor. I would clean or replace the MAF to fix P0171 and hope it also clears the knock sensor code. If not you may to check here:

http://us.lexusownersclub.com/forums/index...sor+replacement

thank you thank you - i sure hope it doesnt end up being the knock sensors - let me add this - the car has been spark knocking really bad at times for a long time - just thought it was the gas - guess not - the 171 code was the first code i had been getting so i will try the maf sensor first then go from there if it doesnt fix it - i really appreciate this forum and your help - i will post back when i have some good or bad news - hey tell me this the two star screws holding the maf in stripped out and i was using a start screw driver #10 - it fit the best - now i cant get them out short of drilling - any suggestions there LOL - yea kind of a bad start already - thanks again

[smgchandler]

fellas tell me this - a local business with one of the newer hi tech diagnostic machines will analyze the car for 80 bucks - will this tell me exactly whats going on and are they usually right and is it worth the money - before i go buying maf and O2 sensors or worse - anyone had this done on theirs before and was it worth it ? thanks

[mikey00]

You are not the first one to have trouble with those screws, others have resorted to vise grips. This link points to IACV screw problems but I thought it may be helpful:

http://us.lexusownersclub.com/forums/index...showtopic=30723

I have not had any experience with the advance machines you mentioned but maybe someone else can comment. For $80 I think I would get it done. Just remember check good for exhaust leaks first. A exhaust leak would most likely even fool that sacnner. In 2000 there was some kind of problem with a exhaust manifold weld and also with the flex piece after the manifold which you will see from underneath the car. These leaks often showed as CELs indicating sensor failures.

You may be able to find additional info on these subjects by searching the forum. (search is at bottom left)

[wwest]

my wifes car has 140,000 miles on it and its paid for so i have to try to fix it myself before taking it elsewhere - tried to trade it before all this happened for a civic and they hurt my feelings so we have decided to drive it until the wheels fall off but im afraid that may be soon if i cant fix it - i have read other topics on this problem but have not solved it yet - OK it started out by check engine light coming on - this was the 171 code so i bought a O sensor -

You could have stopped this dissertation right here....

Until the O2 sensor code is cleared via replacing the sensor all else is a completely UN-educated GUESS.

naturally it was for the one just before the catalytic converter and not the one on the exhaust manifold - so i got the wrong one - anyhow i didnt put it on yet - then the transmission wouldnt go into od and i knew it was low - after this i drained all the transmission fluid twice and refilled with the correct t-4 fluid - reset the light and it did fine for about 20 miles - then light came back on and it wouldnt go into 3 or maybe OD - it was taching about 3000 on interstate - anyhow i tried cleaning the maf or map sensor just behind the air cleaner with the spray cleaner and that did work for about another 20 miles then light came back on - dont know where to go from here - the transmission shifts and sounds acts fine until light comes on and you get out on the road -the fluid was dark but no pieces or hunks on the plug or in the fluid -

i have not changed the O2 sensor yet so that may be the problem and causing the transmission not to shift

EXACTLY...!!!!

- i do believe however that the transmission was low before all this started because it does have a small leak but i never checked it until the car wouldnt pull itself in the driveway - then i checked it and it was low -

i got the right fluid put in it

How low....??

and it did fine then - anyhow this is where im at now - anyone have any suggestions before i take it to a real mechanic ??? thank you for any help here

If your's is a '99 or '00 RX300 with 140,000 miles and the transaxle hasn't yet been overhauled then be prepared to shell out ~$4500.00, if not now then soon.....

'01 to '03 RX300 then only "soon".