jadeboy

iTrader: (1)

After 1 month of flawless performance.. with the o2 90 degree extension sensor installed... today the CEL has gone on again.. unfortunately this time... I unplug the battery and plug it back it.. within a few minutes (even without driving) the CEL comes back on, in the past the CEL light usually comes on after several hours or days.... I have unplug the battery about 4 times without success.

The only other difference I can see is that the weather is getting colder up here in Canada.

Would installing the Vibrant Perf. spacer make any difference?

ilv1004s

iTrader: (8)

did you check if any of your wires havent been damaged?

jadeboy

iTrader: (1)

I don't see any wire damage from the Header 02 sensors.. all seems fine.. and the Gas Cap is tightly in.. so it's not that.. I am going to try to get a reading tomorrow from an OBD scanner... to see what code it produces. The car runs perfectly fine also.. just after the rough 30 seconds start up/warm up from the engine.

montgb

iTrader: (7)

Give it a couple days first. Mine came on again even after the extension was installed, but only stayed on for two days. After that, it went off on it's own and has stayed off.

I can't explain it, but it hasn't been an issue since.

Gaugster

With the pipe welded on, I was still getting the P0420 and P0430 (Cat Efficiency NG) engine codes. Used the additional extensions and got rid of all the codes. It was good timing 'cause I had to bring the car in for its emissions test. Passed np...

I originally used the smallest jet but have been experimenting with the larger diameter jets just to see what happens. Now using the largest jet from the kit and still everything seems ok. I have an OBDII reader so it is easy to clear a code if one pops but luckily nothing has.

With great weather my AWD ran the quarter 15.3 @ 89mph recently. So she is running real good....!

http://www.dragtimes.com/results.php...arch+DragTimes

jadeboy

iTrader: (1)

Ok.. got a reading for the OBD II scannner..

Here are the codes:

P0606: PCM Processor Fault
- I am assuming the PCM processor fault is just the processor complaining that the input voltage from the sensor is out of range... if I fix the error code below... this code should disappear?

P0138: O2 Sensor Circuit High Voltage (bank 1 sensor 2)
- I am assuming driver side, after header 02 sensor.

Additionally.. after clearing the code.. the system seems to trigger the codes again within seconds.. I believe it likely a bad O2 sensor and not related to a leak.




Anyone help?

jadeboy

iTrader: (1)

Additional information:

The car usually starts really smoky for the first 30 seconds.. when the car engine is trying the circulate the oil..

After 30 seconds the smoke is generally gone.. but on the driver side where the O2 sensor is causing the CEL.. it still really smoky although not as bad on start up.. on the passenger side where the 02 sensor doesn't trigger the CEL.. there is hardly any smoke..

I suspect the O2 sensor on the driver side is functioning fine... and reporting an error because there is something wrong.. what would cause the exhaust to send out lots of smoke on the back just on the driver side?

Gaugster

Both exhaust pipes join into one pipe and then split again after the rear axle. So you can't look at the tailpipe output and diagnose a bank 1 or bank 2 issue.

By smoke what do you mean? It should be water vapor only. Take a good look at my exhaust video. It's a cold start in the winter so you can see and compare this "smoke".

I have never had a 02 sensor 'High' reading. Only "low" or "Poor Efficiency". You might have a short in the wiring that is making the sensor read high. Do the wires look to be tightly twisted???

Regarding P0606 - Some IS250s had this code when Mazzuri first made the headers. But it seemed to be vehicle or model year dependent. I have an 2007 purchased early in the year.

Regarding P0138 - Like I said, never had this code (or P0606 fwiw). A high reading means a rich mixture. This could be because of the cold weather? idk. Below are the basic things to check that I found online.

- Harness or connectors (The sensor circuit is open or shorted)
- Rear heated oxygen sensor (Bank 1) may be faulty
- Fuel pressure may be faulty
- Fuel injector may be faulty
- Intake air leaks

Good luck. Did you ever try the Vibrant Perf. extensions??? My welded ones are much longer then what comes with your headers but I still needed it to be longer....

jadeboy

iTrader: (1)

I think it's a faulty O2 sensor.. or it's shorted.. I got another OBD 2 reader which capture more data.. I got a reading of:

Oxygen Sensor Output Voltage (B1-S2) 1.28 V

I can post the complete readout of all the other spec.. if it helps
..

By spec.. the O2 sensor should never goes above 0.90 V.. the value of 1.28 V probably cause code P0606. I am going to take another look at the sensor... but I've already purchased another sensor just in case.. Does anyone have a picture guide on how to replace the Bank 1 Sensor 2 O2 sensor on the 2nd Gen IS?

I was trying to source the Vibrant Perf extension locally.. but I think it will not help my current problem.. because that would fix the voltage when it's too low... I am also considering a O2 Simulator as the last option.

montgb

iTrader: (7)

It seems likely that a faulty O2 sensor is to blame. It wouldn't make sense that the PPE O2 Sensor extension would work on everyone's car but yours.

jadeboy

iTrader: (1)

To be updated...

Bank 1 sensor 2 is on the passenger side after the Cat.. I will check that... all the time I thought it was on the driver side.

jadeboy

iTrader: (1)

Wasted about 3 hours on the driver side, but I know it's the 02 sensor on the passenger side..

If I unplugged the 02 Sensor on the passenger side the CEL comes on with only:

P0037 Heated Oxygen Sensor (Bank 1 Sensor 2) Heater Circuit Low Voltage

A good thing at least it's the same location.

Replacing with a new NGK O2 Sensor.. unfortunately.. I get the same PO606 and P0138 error again same voltage of 1.27.

But I had it working perfectly with no CEL for 20 minutes.. before I did the final installation.. I don't know exactly what I did.. maybe I left the O2 sensor outside and not plug into the weld-on 02 extension...

Will try more testing in the next few days.

Gaugster

It can take days and several driving cycles to get the CEL to come on. Props for the diagnosis and good luck. Just keep working on it and eliminate the possible causes one by one until it is solved.

jadeboy

iTrader: (1)

I took the original OEM 02 sensor and plug it back in but left then sensor out in the cold air without screwing it back onto Weld-on 02 Sensor extension.. same error P0606 and P0138. The CEL comes on within about 5 minutes.

Then I plugged a New NGK O2 sensor into the Weld-on 02 Sensor extension and the passenger side plugin... everything was good for about 15 minutes... NO CEL.. so I decided to drive my car.. then within about 10 minutes.. the CEL goes back on P0606 and P0138... I decided to clear the CEL error.. the CEL comes back within seconds..

Remember if I leave no O2 sensor plug in it gives the error

P0037 Heated Oxygen Sensor (Bank 1 Sensor 2) Heater Circuit Low Voltage only
and NO P0606 error.

So it's definetly isolated to either the Bank 1 Sensor 2 or it's a problem related to P0606: PCM Processor Fault.

I am a little at a loss. There are 2 two options left..

1. Get Lexus O2 Simulator and fake the signal... going to the PCM.. if this doesn't work.. then there is something wrong with the PCM or the wiring to it.

2. Assuming it's a PCM problem or some wiring issues.. and get lexus to reflash or replace the PCM..

Anyone have any other suggestion?

jadeboy

iTrader: (1)

Went to Muffler shop.. had them check for leaks.. there was none.

I am ordering O2 simulator off ebay to try fix this. With the new NGK O2 sensor.. the CEL does goes OFF sometimes (I believe it goes off if it passes 2 times in a row) but then it's back on.

Below is complete freeze frame reading when I get CEL


Parameter Description Value
DTC for which Freeze Frame was Stored P0606
Fuel System 1 Status Closed Loop
Fuel System 2 Status Closed Loop
Calculated LOAD Value 44.71 %
Engine Coolant Temp 185.00 °F
Short Term Fuel Trim - Bank 1 -3.13 %
Long Term Fuel Trim - Bank 1 -0.78 %
Short Term Fuel Trim - Bank 2 -1.56 %
Long Term Fuel Trim - Bank 2 -0.78 %
Engine RPM 1,224.00 rpm
Vehicle Speed Sensor 18.02 mph
Ignition Timing Advance #1 Cylinder 26.00 °
Intake Air Temperature 21.20 °F
Air Flow Rate Mass Air Flow Sensor 1.88 lb/min
Absolute Throttle Position 20.00 %
Oxygen Sensor Output Voltage (B1-S2) 1.28 V
Short Term Fuel Trim (B1-S2) 99.22 %
Oxygen Sensor Output Voltage (B2-S2) 0.02 V
Short Term Fuel Trim (B2-S2) 99.22 %
Time Since Engine Start 2530 sec
Fuel Rail Pressure 1,150.15 psi
Bank 1 - Sensor 1 Equivalence Ratio 0.95
Bank 1 - Sensor 1 O2S Voltage 3.00 V
Bank 2 - Sensor 1 Equivalence Ratio 0.97
Bank 2 - Sensor 1 O2S Voltage 3.14 V
Commanded Evaporative Purge 76.47 %
# Warm-ups since DTC Cleared 1
Distance since DTC Cleared 11.18 mi
Barometric Pressure 26.06 inHg
Bank 1 - Sensor 1 Equivalence Ratio 0.95
Bank 1 - Sensor 1 O2S Current -0.1835938 mA
Bank 2 - Sensor 1 Equivalence Ratio 0.97
Bank 2 - Sensor 1 O2S Current -0.09375 mA
Catalyst Temperature Bank 1 - Sensor 1 1,121.18 °F
Catalyst Temperature Bank 2 - Sensor 1 1,121.18 °F
Catalyst Temperature Bank 1 - Sensor 2 1,121.18 °F
Catalyst Temperature Bank 2 - Sensor 2 1,121.18 °F
Control Module Voltage 13.75 V
Absolute Load Value 33.33 %
Commanded Equivalence Ratio 0.99
Relative Throttle Position 3.92 %
Ambient Air Temperature 12.20 °F
Absolute Throttle Position B 52.94 %
Accelerator Pedal Position D 24.31 %
Accelerator Pedal Position E 40.78 %
Commanded Throttle Actuator 20.00 %
Time since DTC Cleared 0 hr42sec