thomaszr

I have a 99 RX300 with 180k. It runs fine at first but loses power and won't go very fast after it gets warmed up.

I pulled these 3 codes from it. P0125, P0330 & P1135.

Any ideas or suggestions would be appreciated.

Thanks in advance.

carguy07

Air/Fuel Sensor in in bank 1 (the one closest to the firewall. https://www.clublexus.com/forums/rx-...el-sensor.html

thomaszr

Thanks carguy07.

That makes sense.

I've read so many different posting online that I've kinda over thought & confused myself.

I was thinking along those lines because I've only ever had to change the one in the front of the engine.

(& I had to take off the exhaust manifold and put it in a vice to get it out)

Cross your fingers...

thomaszr

Sensor ordered; patiently waiting...

thomaszr

The firewall side fuel sensor finally came in and I installed it today. (Was a PITA to get out; wiggle, wiggle, spray, spray repeat x 30 & then re-tap...)

It ran good all the way home. (about 15 minutes at 60 mph).

About a block from my house the check engine light came on.

I pulled a P0330 Knock sensor 2 circuit ban 2 error code & a P0446 Evaporative Emission system vent control circuit pending code.

It seems to run ok. I cleared the 2 codes and will test drive it more tomorrow.

Any one have any ideas what I should do next?

maxSteel

The P0446 code won't return until the car goes through the full test cycle, which is affected by speed, fuel level, time, etc.
Make sure gas cap was tightened properly.
If the code comes back you can try a new cap, or proceed directly to testing the canister and VSV's.
There is a big thread on this

The knock sensor might need changing. Big thread on this too.

salimshah

Pending code may become real or it may disappear. It is like an error was logged, but it needs to be reported again [not sure how many times] before it becomes real. I would not change a pending code.

Salim

thomaszr

Argh, I've cleared/erased the 3 times with my code reader and the P0330 & P0446 keep coming back...

It seems to run ok but I have a dream of one day driving without the "check engine" light on...

:-(

salimshah

P0446 can be diagnosed lot better with an advanced reader. There are two solenoids involved and pressure monitor. Live reading will be able to pinpoint which is malfunctioning or a leak in the hoses.

Knock sensor usually last about 140-160k miles. It can be the wire too. If left unattended, you will be locked out of the overdrive.

Salim

thomaszr

I guess it's" good news / bad news" situation.

Good news is after I replaced the Canister Purge Solenoid (NAPA #CRB 228207) near the fuel tank the P0446 code is gone.

Bad news is now I have a "P0171 System too lean Bank 1" one... :-(

From what I've read it sounds like a vacuum leak.

I haven't found any leaks and I'm wondering if the difference in the replacement part could have anything to do with it. (see below)



The 2 hose connections on the original part on the left are opposite of the 2 connections on the new part on the right.

I had to reroute the connections with longer looping hoses. (I made sure they were snug and not kinked)

Does anyone think the reversed connection part could have anything to do with it?

PS: I still have the P0330. Replacing the knock sensors is on deck.