P0136 - Oxygen Sensor Bank 1 sensor 2 malfunction

ok, i'll go disconnect it since I have 1.5 hours left of work.

 

Well, after disconnecting the battery, of course the CEL was off but P0136 was still permanent (which was to be expected). Started my commute with AFS voltage between 3.2-3.3V on average. I noticed when I would brake, the voltage would jump to 5v. The Short Term Fuel Trim was consistently around 1-2%. But both AFS and STFT were bouncing around every second. The heated o2 sensor was at Zero volts (possible it was in the millivolt range though?) for 20 min of highway driving until i hit the interstate, at which time it started fluctuating between 0.5-0.8 Volts. When I arrived at home, P0136 was permanent and pending.

This morning, AFS and STFT were the same ranges as mentioned above, heated o2 remained at zero the entire drive. Maybe 5 times did it create a blip for a 1/2 second. The CEL did come on at 12 min into my commute with a now stored P0136 code. Fuel economy was averaging 38.2 mpg (again, better than before this code showed up). Would the EGR valve have anything to do with this lack of voltage somehow? I'm tempted to swap out my cleaned one since that's one of the suspected items listed in the manual.

I did not get a chance to measure resistances last night (the kitchen was trashed and I can't go to bed with a dirty kitchen :s)

I'll update with those values once I get the time to jack the car up and get at those parts. Until then, I'll just continue to deal with it. I just hope i'm not destroying the catalytic converter.

 

So, ugh, the CEL was off this morning and when I got to work, the code wasn't even pending.

To answer your question Critic, I honestly don't think they told us what year the new engine came from. I only remember they told us it had 90k miles on it and was the only one available from the "reputable" source they get used engines from (this was Lexus service mind you). They claimed they did all sorts of inspections and tests, cleaned everything before they installed it (which I am seriously questioning due to lots of sand, dirt, bugs, etc all over the engine casing). I wish I had spent more time researching about this engine problem prior to having it as I would have pushed for a completely different fix. Hindsight is always 20/20 i guess.

 

I have the sensor, but didn’t have time to get it on the lift yet. Lots of life things pulling me in different directions.
I noticed my mpg started dropping and checked the codes. Now I’m getting p2238 front sensor code.

Gonna let the car cool and kids to bed and try tonight to change.


-Spiral

 

got the new one installed (included pic of both the old and new sensors. I hope the blue/purple sticker doesn't mean anything?), cleared the codes and took it for a little spin. Didn't do the "Drive Pattern" though. I also didn't pull the neg battery lead to reset Longterm fuel trim. I have a bunch of stuff back there and just didn't want to deal with it tonight.

Here are the VOM readings:
AFS Old: HT/B 2.4Ω (1.8-3.4Ω spec)
AFS Old: HT/AF- OL or greater than 10k Ω (>10kΩ spec)

AFS New: HT/B 2.8Ω (1.8-3.4Ω)
AFS New: HT/AF- OL or greater than 10k Ω (>10Ω)

Heated O2 Sensor: HTB1/B 12.9Ω (11-16Ω spec)
Heated O2 Sensor: HTB1/E2 60k Ω (>10kΩ spec)

I'll give it a couple days (drive cycles) and see what happens. I guess time will tell.

 

Well Critic & cnc97. No CEL on drive to work this morning. P0136 code pending and permanent as well as the P2238 permanent code when i arrived. As I leave the parking lot at lunch to get fuel, CEL came on. Filled up the tank, put car in IG on (non-ready) mode scanner came back "No DTCs Present". put it in ready mode, CEL still on, read codes again with No DTCs present. Shifted into drive and CEL turned off. Went out onto the backroads to perform Drive Cycle and before starting the 10 min portion, code came back for Crank Position sensor (wasn't pending/stored/permanent...just present?). Anyway, did the drive cycle (10 min above 38 mph in maintenance mode, slowed to idle, shifted into "B", hard accel for 10 seconds, let car slow to 5 mph without brake, accell for 10 secs....did that 6 times) returned to work and read codes, "No DTCs Present". So...fingers crossed...it stays like this. I'll update if something else happens.

*side note, I can't seem to edit above posts, so i thought I would update my original AFS part number as i had one number incorrect: 89467-52060

 

well THAT didn't last long. CEL was off during my commute to work. P0136 pending/stored/permanent when i left for lunch.

Now I'm torn though....I feel like I should focus on the EGR or Intake with MAS...but if the EGR needs to be cleaned, do I push for the dealer to do it since they said they cleaned it at the time of the engine swap. or do I just put in my already cleaned parts and not waste my time with the dealer. hmmmmmm.

 

I don’t have techstream yet. I actually don’t have a laptop that meets the criteria. I did start to dig into everything to figure out all that’s involved, just haven’t had put that much effort into it.


-Spiral

 

Drat, I’m in Illinois, though I would love to be in the Bay Area instead of here


-Spiral