1999 Lexus RX300 rx from North America - Comments

I have 2002 lexus RX300 and the check engine light came on when code P1155 A/F senor heater circuit malfunction (bank 2 senor 1)

The MAF sensor is right next to the air filter box. You can unscrew it. Disconnect the electrical plug and clean it with alcohol spray and wipe down.

Should we buy a 1999 RX300? Seems like there are a lot of problems.

Can anyone tell me where the 2 knock sensors are located? I see one switch on the right (passenger side) of the engine screwed into the manifold (I believe). It looks like pictures I have seen of the part. Where is the second sensor? I can't see it.

Thanks, Ron.

The knock sensors are located under the manifold. Bank 2 is near water outlet and bank one is further under manifold. Just pulled my plenum and manifold off (not an easy job).

I have a 2001 Lexus 300 RX with 280,000 Kms on it. This car has been well maintained - visit to the garage every 5 - 10,000 km. What is happening now is that my check engine light and VSC lights both come on sometimes. I have been told to replace the knock sensors - but am not sure this is the problem!The reason I am not sure about this is that these lights do not come on all the time - sometimes several weeks go by and they stay off - but then come on for a day or two.

My rpm's do sometimes increase - but by stopping the engine and re-starting - this seems to solve the rpm problem.

I also have noticed that using a higher grade of gas seems to keep these lights off.

The air filter was replaced in April, 09 and two VSC sensors were replaced in Feb. 09.

My 1999 RX300 will not shift into overdrive after running for 5-10 minutes. The check engine light yields codes P0171, P0325 & P0330. A dealership wanted to replace the MAF sensor and both knock sensors to the tune of about $1,500. Does anyone have any suggestions? Why would the transmission shift into overdrive for the first 10 minutes or so? I don't hear any knocking either.

Many thanks!

My suggestion is to trade it in if it is at all economically feasible for you. My personal experience with a 99 RX300 is once things start going on them, they become a real money pit.

We traded ours a month ago and are very happy that we don't have to pour money into it anymore.

One the other hand - they do have a lot of positives until they start wearing out.

Good Luck.

"My 1999 RX300 will not shift into overdrive after running for 5-10 minutes. The check engine light yields codes P0171, P0325 & P0330. A dealership wanted to replace the MAF sensor and both knock sensors to the tune of about $1,500. Does anyone have any suggestions? Why would the transmission shift into overdrive for the first 10 minutes or so? I don't hear any knocking either.

Many thanks!"

Try having your transmission fluid flushed and replaced. Then have the codes cleared. Drive it for awhile, and if it comes back, then your dealer might be correct about those problems. But try these solutions first as they are much cheaper.

Do not bother with having your tranny flushed... it is the check engine light (knock sensors) that is causing your tranny not to shift. I too have the same problem. Getting my knock sensors done Monday, will update you all with the results.