when the ECT sensor showed -40 the air intake was +40 based on the freeze frame
but all worked fine yesterday at Orileys on the live scan tool
CEL came back on the drive home though.
no batt light comes on... i have an after market volt meter on my tpms display that shows V
at idle it occasionally will drop below 10 v
most of the time will charge above 1000rpm 13.7v

I was thinking maybe when V drops a bit below 12 it trips something into thinking ECT sensor is too high

its the downstream o2. replaced but now have code ....circuit failure.. not sure if heater out or o2 signal is faulty
I should go back and see live data for o2's .. i forgot at the time.

 

so i could only see o2 sensor 1 on bank 1 and 2
the scan tool would not show live feed from sensor 2 (downstream)
code keeps coming back po137 (circuit failure) low voltage. on that downstream o2
so its still too cold out to attempt the alt rebuild so I ordered another o2.
hopefully its not a glitch tripping the code due to alt cutting out briefly at idle.

 

nah the alt will not affect the 02 think about this the pcm gives a 1 v max out put to the o2 sensor, the alt when it fails will automatically put the batt into supplying current to the pcm so tht wont be an issue
if your car is a 99 that sensor is way past its sell by date

 

o i could only see o2 sensor 1 on bank 1 and 2
the scan tool would not show live feed from sensor 2 (downstream)
code keeps coming back po137 (circuit failure) low voltage. on that downstream o2
so its still too cold out to attempt the alt rebuild so I ordered another o2.
hopefully its not a glitch tripping the code due to alt cutting out briefly at idle.

how many sensors you changed just 1

 

i replaced the downstream 1 a few weeks ago but I keep getting codes from that one over and over.
so i ordered another 1.

my ECT has not triped any code for a while.. reads normal
IAT read 105 deg on a freeze frame yesterday ... temp outside was like 40 deg at the time
hope thats ok

 

105 is normal what sensor did you get was it a Bosch
I got 3 Bosch's for mine and they are working fine so far 3 yrs
Is the wiring harness sound? Have you changed the other 2 sensors - on the manifolds? seems odd that a new sensor would trip a code .You can probably switch it out from near the cat conv with one of them on the manifold just to make sure its good or its the harness is bad

 

I replaced just the 1 o2 w an ebay special.
I ordered another from rock auto .... not the bosch.. it was too much
will be here friday.. hopefully my mechanic can get me in quick. its still cold here!
need desperately to get everything resolved asap i have an 1800 mile trip planned soon

 

Sorry to bring up an old thread. You mentioned that something used to happen whenever it was wet. What did you do exactly to fix it?

My 98 RL recently just died. It happened to my sister once and I don't remember if it was raining for her but it was definitely raining hard the whole day for me (although not when this happened). I was on the highway and suddenly giving it gas did nothing. As I pulled over, all lights were on, CEL was flashing, RPM was very low. I shut off the engine, two minutes later restarted and now just CEL (not flashing) and the car drove fine. Codes were similar to yours where it showed misfire. Exact codes are P1201, P1202, P1203, P1204, P1205, P1206, P0300, and P1399. Similar to yours, I cannot reproduce it. Hasn't happened in a while and when it does, seems to just go away when I restart.

 

i spent $1000 on chasing ghosts. replace one coil then the next then the next.. same thing for half the injectors... replace #1 then #2 shows a fault. its all just shorts caused by water leakage onto the fuse panel on drivers side kickpanel. there was a post about removing the fender and siliconing up all the wiring harnesses behind there. i havnt done it yet as i moved to a dry state where there is only rain a few days a year. but when i go through a car wash water drips on my left ankle. so seems like leak is definitely on that left window pillar down to the fuse panel. it has wrecked havoc w all sorts of systems including tripping factory alarm and even my aftermarket alarm. and if your cd changer stops working or trunk is wet.. remove the tail lights and silicone the hell out of the gasket. i had so much water i drilled holes under my spare to drain the water

 

in regards to my o2 problem.. after replacing it several times i just bought an o2 extension.. also known as a spark plug anti fouler .. you may need to dremel the inside to fit all the way in but it stopped my cel from coming on