2007 RX350 - Alright, so after 8 days of driving after resetting the P0158 code, my CEL came back on.

So I ran it down to my mechanic and he pulled the codes listed above. P0158 was the same code that he pulled over a week ago for the Oxygen sensor. P0158 - Bank 2 Sensor 2 - Circuit High Voltage.

But accompanying this was the P0606 code as well. I found one thread here on CL with limited help, but found some other info out there in general population...

1. "P0606 can be caused by the impedance in one of the o2 sensor not dropping when it should. This causes the ECM to think it has an internal issue. If you can see the data list look for the impedance of the o2 sensors, run the engine and watch to see if they start dropping - the one that doesn't drop is the one that needs to be replaced."

2. the PCM/ECM processor fault is just the processor complaining that the input voltage from said sensor is out of range.

3. P0606 LEXUS - ECM Processor Failure

Symptoms- Engine Light ON (or Service Engine Soon Warning Light)
- Engine may not startPossible causes- ECM Harness power supply circuit is open or shorted
- ECM Programing
- Faulty ECM

Possible solution- Resecure ECM connectors
- Reprogram ECM
- Replaced ECM

Tech notes
Check the ECM fuse, if fuse is OK try erasing the code first and if the code comes back you may have to reprogram or replaced the ECM.

When is the code detected?Indicates the ECM has experienced an internal memory fault.P0606 LEXUS DescriptionThe ECM continuously monitors its internal memory status, internal circuits, and output signals to the throttle actuator. This self−check insures that the ECM is functioning properly. If any malfunction is detected, the ECM will set the code and illuminate the engine light.

SOOO....Here goes...

I want to get thoughts/opinions that the ECM is probably being caused by the o2 sensor.
From everything I read, this is most likely the case given the high voltage info.

I found this link in CLForums on the sensors: https://www.clublexus.com/forums/ls4...t-numbers.html

Would the sensor location info match up to my RX350? Any info would help.

The Bank2 Sensor 2 Bosh part # is 15758 from AutoZone, or Denso 234-4509.

Bosh at AutoZone = $175.99
Denso at AutoZone = Not Avail
Amazon Denso = $82.54 (http://www.amazon.com/Denso-234-4509...2007&carId=001)

Plan is to buy the sensor and have my vodoo mechanic install it.

Any help to point me in the right direction on the sensor info, and thoughts on if you think this will solve the ECM would be great. Any flaws here?

 

My vote would be for Denso if you purchase. Bosch is great for European vehicles, however, Denso is OEM Toyota for many things like plugs and such. Was a great price as well.

If it does not solve the problem at least you will know what it is not, without breaking the bank. Can always hold the pulled sensor for later testing.

Will allow others respond to the rest of your questions.

 

Okay - I replaced the faulty O2 sensor, but it turned out to be one of the sensors BEFORE the Cat. With a better code reader, there were 2 sensor codes tripping, so fixing the pre-cat O2 sensor "cleared up" that problem.

New problem, I'm getting a P0355 code, cyclinder # 5 misfire.

I took it to my local mechanic and he said that he checked all of the hoses/wires and found that everything was in place. The check engine light is SOLID for 99% of my driving. The only time it becomes 'blinking' is when I have to accelerate uphill from a stop at 1 or 2 redlights around my home. Other than that, the car drives fine. (One random note, I have been extremely LIGHT on the pedal not trying to make the engine work, and I am avg 21.8 mpg. My "normal" driving is 18 mpg)

I have decided to grab a second opinion at Firestone, after speaking with the tech there when I was putting tires on my wife's Sienna van. Tech said that they have a really good computer analysis tool, so I thought I would let him diagnose it just as a precaution (I trust my mechanic but he has been the only one working on my RX350, so I thought a fresh set of eyes would be good.)

I called the shop preemptively, because I am impatient, and he was not yet done with his dagnosis but provided the following thoughts and info:

1. There are 8 codes stored in there, including the P0355, and they all point to the Cyl 5 misfire (he was at the phone, not the computer, so he did not provide all the codes, ugh...)
2. The #5 ignition coil is reading the correct voltage, and it is the same voltage as the other coils.
3. All cylinders have shown significant misfires in a cycle, and a pre-ignition code is in the computer (I didn't get what code)
4. He checked the MAF sensor and it is working properly, and it is pretty clean. He stated that it only matters if it is dirty enough to change the voltage.

Given this LIMITED explanation, I am still hoping for the best case scenario that a vacuum hose or wire needs replaced or clean the MAF anyway. I understand the complexity of these engines is to make diagnosis easier, but after already fixing an O2 sensor, it really looks like we are stepping backwards looking for the real problem. I just hope I'm not fixing too many things along the way. I really hate to head to the Dealership but I'm afraid if things get to complex that may be my only option.

Anyone want to share their thoughts / ideas on what it could be?

 

Depending on what state you live in the O2 sensors can be covered for 8yr/80k miles under the Emissions Warranty.

You have a lot more faith in these tire store mechanics than I ever would. I agree, it might be time for you to consider a trip to the Toyota or Lexus dealership.

 

The vehicle sits at 90,000 miles. I asked for any ideas or leniency to no avail.

I spoke to two lexus dealerships, each about 45-50 min away, and there was a two week wait to get in.
Shop was 5 min from home, and could check on it immediately. That is too long for me, and too far to drive just to have them scan it.

Any ideas on problem or ideas are welcome.

 

The codes my car (2007 RX 350) is giving off now are:

P0355
P0300 (random misfire)
P0301 thru P0306 (specific cyl misfire)
P0158

Am I right to assume that 1 bad coil (#5 per 0355) can trigger all of these?

I've also been told that my "air flow ratio" sensor is bad. I asked if he meant my MAF sensor and he said no, it's the one near the catalytic converter...so I think he meant an O2 sensor. But the guy on the phone was the front of the shop, not the tech himself so he'd confirm in the morning what he meant. He said the tech wanted to start here, but I'd think this is downstream of the real issue, the # 5 coil pack...

Thoughts?

 

Update to summarize problem ...

Had my 2007 RX 350 taken back to the dealer. They performed their diagnosis and identified the same codes as listed above. They replaced the # 5 coil pack, and to my complete surprise, the total was $290.00 plus tax. I was REALLY bracing for a larger bill based on some of the posts I've read here. Came to $311.00 with the tax.

They identified one other thing that is unrelated to this issue, so I will not post it here because it belongs in a different thread.

Overall, I am very happy with the speed and service that the guys provided to me. They got my vehicle right in, called to provide an update and ask for approval to do the work, and then called with the final word. I am crossing my fingers in hopes that my CEL problems are a thing of the past... (I could do for a year, or maybe 10 months without one...)

 

Thanks for keeping us up-to-date and thoroughly informed. Glad to hear this may finally be coming to an end for you.

 

Annnnd I'm back.

So car ran great for 4 days and the CEL came back on. Took it right back to the Lexus dealership for them to check it out. (Off topic - they handed me the keys to a 2012 RX350 that was loaded. Man that thing is SWEEEET. Wish I had some where to go in it)

Turns out, it is tripping Bank 2 Sensor 2 - AGAIN (P0158). This is the FIRST thing my local mechanic replaced, and when he did it, the threads must have been stripped b/c the dealer said it was spot welded on. I went to the store and bought some Fuel Injector cleaner, some MAF cleaner, and a O2 sensor wrench for the hell of it. It made me feel like I am tackling something today as I wait for another sensor from Amazon.

In the meantime:
1. Lexus gave me lexus part number: 89465 0E020
2. Auto Store gave me Denso Part # 234-4509 (which I used 2 weeks ago also)

Q1: Are these parts IDENTICAL? Is Denso really OE and just diff #?
Q2: Could there be a short or something causing the sensor to fail? (I'm sure the spot weld did not help things on the sensor)

Any thoughts?

Wish that were the truth! But I'm sure it's warmer in FL than Steeler town...

 

I did say "may." Sorry to hear things are not final, yet.

And, far hotter still in hell.

The Toyota/Lexus parts have their own numbering scheme. They may be Denso, they may not. They may also be multi-sourced to provide enough parts for Toyota/Lexus to use. If the OEM is Denso, the part they would sell to Toyota/Lexus would be identical or nearly identical but would more than likely have its own part number for sale through parts warehouses.

 

Do you, by chance, have the first sensor pulled from your RX? I would say to compare that original part with the new one your get and with the one you pull that is defective as a comparison. Or, perhaps you can compare while the repair is ongoing or after the fact.

 

Unfortunately, I do not have the sensor that was originally pulled. B/c that would have been too easy... Totally didn't think of it... ugh...

Related to this effort of determining/confirming sensor location and part # required...

Can someone please confirm the following info for me as the various threads I've read seem to point to different locations for the sensors.

To start, what sensor is IMMEDIATELY in front of me when I open my 2007 RX 350 hood? I've been told by a lexus tech that BANK 1 is the same side of the engine as Cylinder 1, and Bank 2 on the 'even' side of the engine..translates to Engine LEFT, or Car FRONT on the RX 350.

Therefore, Bank 2, Sensor 1 should be the first sensor I see when I open my hood, right? It is "easiest" to change, and is the "upstream"

That would also mean that Bank 2, Sensor 2 can be seen from below the front of the car looking up. It is pretty easy to identify when under the front of the car. If you can find the oil filter, it is in about the same spot but towards the drivers side of the car. I would say this is the "2nd easiest" to change and find once you remove the plastic dust-sheild. It is "downstream"

By process of elimination then, the Bank 1, sensor 2 will be the "3rd Easiest" to locate when crawling directly under the middle of the vehicle. In the RX350, I would say this is below the center console in between the driver and passenger seat. Really easy to see I think.

That leaves us with Bank 1, Sensor 1, which I have to admit, seems rather difficult to get to (but again I did not remove the plastic dust-shield.)

Lastly, I believe that the "upstream" sensors are also referred to as "A/F Sensors" and the "downstream" sensors are referred to as the "O2 Sensors." Right?

I took some pictures of each of these but would prefer some confirmation that my identification of each sensor above is correct. It seems that there is a lot of mis-information out there on location, even among some of these threads. Thanks for the help...

 

So here's an update.

Lexus dealership had car, identified B2 S2 needed replaced. The tech calls and tells me he needs to replace the whole manifold. I ask why... I'm told the sensor is welded in. I tell Lexus not to do anything, get my car, and take it back to my local guy to see what's up.

I feel like I've been playing sensor roulette here. I want to find out what sensors were changed, and confirm the exact locations of all sensors. Local tech throws it on the lift.

I gasp....the sensor looks welded. I get a shop rag and start cleaning it up and try to inspect it's wires. After 10 seconds, everything that looked like a weld turned out to be just a bunch of anti-seize and Pittsburgh dirt. Bottom line, sensor comes right out, and I replace with a Bosch. Again.

We Scanned and cleared the code for P0158, B2 S2 O2 sensor. Then Cross fingers.

Everything is fine For 2 days, and then my trusty CEL comes on again. Ugh

I disconnected the battery, removed and cleaned the MAF with MAF cleaner, inspected all vacuum lines, pulled the ECM fuse, and tried to further inspect my sensor wires for ANYTHING. I ordered a scan tool / reader to arrive in a day or so. my plan is reconnect battery in the morning, drive up my small ramps, and LOOK and LISTEN for any exhaust leaks.... (Btw, anyone have a good idea to do this step?)

When i get my scanner I will then scan all sensor voltage once I figure out How to do so with my tool....

If my above home remedy does not keep my CEL away, and assuming it is still Bank 2 Sensor 2, AGAIN, what do I do next?

Thanks

 

Why Bosch? To me it is not a good idea.

Salim

 

sorry to hear about your problems. My experience with any codes for misfires is ignition related
coils, plugs, wires.

as far as your exhaust codes, a good code reader would direct you to which bank is malfunctioning.

its frustrating to track down error codes . kudos to you for having a lot of patience.

i suggest to look for lexus specialist ,that would be cheaper than the dealer.

good luck. i also have a 2007 rx 350 and this will be very informative issue.