Gunner41

Morning ya'll.

We have a 99 RX300 that were trying to get to pass smog. We have a P1346 "VVT Sensor Rang/Performance Problem (Bank 1)". Took it to the shop and they did their diagnosing and replaced the Cam (1) position sensor. Ok sure but it wasn't the problem. They didn't know the problem. Took it too another shop. They at least plugged in and tested the OCV. Bank 1 sticks. They removed, cleaned it and replaced it. Same problem. They now said that they have to pull the covers of bank 1 (R/S firewall). I asked about the filters and they scratched their head.
Alright enough of my sniveling, I replaced both OCV, filters and changed the oil. I switched the NEW cam positing sensor to the other bank hoping to change the code. Nope nothing worked. So now I'm thinking that its the cam phaser or tone ring? I seen ways to test it and Im good with it, now the tone ring I have no idea since its pressed on the cam.
Does anybody know if there's anyway to test the phaser or ring without tearing into the engine? I don't like messing with timing unless absolutely a have too. Thanks guys
Oop. Its a 99 RX 300 3.0

salimshah

When was the timing belt changed?

It might be worth checking the alignment marks on main and the two cams ... specially the cam1.

You can try to locate some one in your area who is good with the new type of vehicles. By back probing and scoping the sensor wiring one can observe what is going on. Without it you are poking around in the right area but swapping parts is like hit or miss and it seems you have been missing.

Also check the condition of the wires in the engine bay. First gen RX usually runs hot and the insulation may have been compromised specially if any previous work was not done meticulously .

Salim

Gunner41

I forgot to add that sir. We pulled off the timing cover and all the marks line up and no slack exist. Good call on the wiring. The speed sensor connector needed to be repaired but it works now. We didnt even have issues with it. Unfortunately I don't have too much confidence with the shops out here. We might just have to pony up and sell the house and take it to the dealership. I don't really want to dig into the Phaser unless I know that that is the problem. Thanks again Sir.

maxSteel

Salim asked, when was the timing belt changed? Historically most roads will lead there.

The diagnostic only lists:

• Mechanical system malfunction (Skipping teeth of timing belt, belt stretched)
• Engine ECU

Probably wiring and connectors to ECU could also be at issue.
I know you mentioned the camshaft position sensor but there are other codes for those, and you aren't reporting them.

Gunner41

About a year ago with the water pump. The only other DTC was P1730 (Revolution sensor) The wire was frayed but the shop repaired it. No other DTC has returned. Its still a great driving car other then the Idiot light and the smog shops. We have not noticed any issues with driving.

I was reading another place about the P1346 and Im thinking that ya'll right again. When I swapped the sensor from bank 1 to 2 I didnt check the connectors
and the same with the OCV. Im going to pull air box and back probe all the sensors like you guys said. Man do you know how dangerous I would be if I were a mechanic instead of a old retired soldier. Thanks guys

maxSteel

A year ago sounds both too old to be a bad install and too new to be a bad belt or tensioner. Bummer.

You're in the rabbit hole for sure. If you don't have one perhaps you might consider the service manual available from Rock Auto https://www.clublexus.com/forums/rx-...rock-auto.html
I bought one even though I have a lot of docs I collected over many years. For $20 plus shipping it's totally worth it.
This is what's in it:

Gunner41

It is on the list. Since they made Alldata so dang expensive cant afford it. I have always had a manual for my cars but this one is new to me. Mind if I ask one question? Here goes. When Im back probing the OCV and sensor what would be the correct voltage ya think? I read 12.0 but have no way to confirm. I might have to borrow my sons "O" scope and learn that thing.
Thanks for the help guys.

Gunner41

salimshah, maxSteel
Thanks for the help guys. I did learn a lot of new fangled technology. Never knew what VVT was but now its like Whoa... Let me summarize what I did for this vehicle.
Replaced both OCV, Filters, Cam position sensors, pigtail to bank 2. (Connector broke when I was switching the sensors around to see if the DTC went from 1346 Bank 1 to 1350 Bank 2. It did the second time I swapped them. that's when I replaced the second sensor. The filters really were not that bad but I replaced them anyway. Both OCV were replaced. Tested the old ones but seem to work fine. I even replaced the oil cap.
I had my son bring his O-scope out so we can see the patterns. Had a problem with B1 at first but it went away. Back probed both connectors and it ran fine. Followed to ECU and probed output. It seemed to work fine.
We tested every connector we could find with this car. Now originally I was thinking Phasers because it seemed that the problem only happened when on a drive and stepping on the fuel in stead of sitting in the driveway. Unfortunately because we live in Ca the smog ***** were breathing on us to smog or sell so my brother in law traded it in for a newer car so I will never know. With that being said Im heading to pick and pull in a couple weeks to pull a Phaser. I just want to see. Besides my ES330 has virtually the same engine.
Anyways guys sorry that its long winded but in the future somebody might need to hear my struggles and your wisdom.
Thanks again Sir's.