Lexus Troubleshooting Questions? Ask a Lexus Expert
The check engine light is on with a lean condition code. Vehicle has 150,000. Transmission serviced at Lexus dealer at 100,000 fluids and filter changed. Fluid was dirty. Today fluid is again dirty. I have owned vehicle since new, driven lightly. At operating temp is when problen occurs. Transmission shifts normally when cold then refuses to upshift to overdrive after 10-20 miles. It has been doing this for 4 days and about 300 miles. I am going to flush the fluid and change the filter tomorrow hoping this will help. My mechanic things there may be wear in the transmission causing the malfunction
The codes are P0171, P0330.
Thank you for the code reading and advise. I cleaned the mass air flow sensor and the 0171 code cleared. I flushed and changed the transmission fluid (it was due for service) and the transmission still fails to upshift into overdrive after 10 minutes of driving (when engine is cold overdrive locks out, then for a few minutes overdrive is available and stays locked in until car slows and shifts down, from then on no overdrive). Now the code P0330 returns and indicates knock sensor 2 is the fault. Do I need to change both knock sensors or is it safe to change just #2 on the front cylinder bank? The time estimate is 3.3 hrs for the change so doing both would make sense except that the sensors are $216 each from the dealer. I found knock sensors on the internet mailorder for $157.02 each, is it safe to uses aftermarket parts for this? Is there a specific parts number for the 1999 model? Is the harness a separate part? Do I need anything else besides the manifold gasket for the reassembley? Thanks for the great advise.
Thank you for the reply and follow up, I figured cleaning the sensor would clear that code and resolve the issue (as well as save you from paying for a new sensor!)
We already touched on the knock sensor issue previously, as I stated if there is no signs of rodent damage to the harness then proceed as I recommended. YES these sensors are VERY expensive but you do NOT want to pay another 3.3 hours labor to go back in there if the other one fails. No do not use aftermarket parts, if you are looking for a wholesale price on OEM factory toyota parts then go to www.metrotoyotapartsnow.com and order BOTH sensors as well as the sub wiring harness for these sensors (it will crumble when removed from the old sensors).
Let me know if you have any follow up questions, thanks.
metropartsnow.com has knock sensor part # XXXXX for engine 1MZ-FE Sienna which appears to be equivalent to the lexus pasrt number 89612040 called for on RX 300 1MZ-FE on Alldata, Are they interchangeable, identical? Metro did not offer the Lexus part.
Thank you, Will