Bunch of Problems 2001 Camry

Messages
429
Location
Metro NY
Hello BITOGERS, The car I am asking about is a 2001 Camry V6 1MZ-FE w/210K miles. Recently a CEL appeared during a drive back from school. I have an Autel MaxiScan MS300 CAN OBD-II Scan Tool that I used to read the code once I got home. The DTC I got was a P0141 O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 2. So I'm assuming that the issue is an oxygen sensor hopefully. I purchased a Denso 234-4137 O2 sensor to replace my hopefully faulty post-cat sensor. Okay, here's where the problems kick in. I am due for a NY State inspection by the end of the month. However when I checked my OBD II readiness status on my Camry using the Autel scanner this is what I got back: MIL - ON Misfire - Ready Fuel - Ready CCM - Ready CAT - Not Ready HCM - N/A EVAP - Ready 2Air - N/A A/C - N/A O2S - Ready HO2S - Ready EGR - Ready I am very confused why my CAT readiness status is showing up as Not Ready. Also, if I'm throwing a P0141 code (related to the O2 sensor) wouldn't the O2S show up as Not Ready as well? I'm assuming that the faulty O2 sensor is not letting the system monitor the converter properly, therefore showing that the CAT is Not Ready. Hopefully someone here can set this straight for me. I plan to get my post-cat O2 sensor replaced this Saturday and do the inspection that day as well. However I was told that once the work is done to the car and the DTC cleared, the Readiness Monitors would not be "ready" to pass inspection. I hope someone could help me solve these issues. Thanks
 
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dgee

Thread starter
Messages
429
Location
Metro NY
Originally Posted By: spasm3
Was the engine up to temperature? The cats have to heat up.
How would i go about checking this after warmup? -hook up scanner -turn ignition to ON -check readiness status?
 
Messages
10,008
Location
Upstate NY
Check readiness after driving for 20-30 minutes. EPA regulations let you have 1 emissions monitor not ready to pass inspection. Is there a separate code for the upstream O2 sensor? Then you'd know for sure which sensor it was.
 

dgee

Thread starter
Messages
429
Location
Metro NY
Originally Posted By: sciphi
Check readiness after driving for 20-30 minutes. EPA regulations let you have 1 emissions monitor not ready to pass inspection. Is there a separate code for the upstream O2 sensor? Then you'd know for sure which sensor it was.
how about a CEL? would that be an automatic fail?
 
Messages
5,651
Location
Iowa
While you're at it, replace the front O2 sensor as well. If it's never been done, it will net you an increase in mileage. After you replace the sensor(s), clear the code and take the car for a nice 30 minute drive with varying conditions. From side streets to the open highway and recheck your monitor.
 
Messages
11,660
Location
NorthEast
You should NOT erase the code. If you erase the code, everything will go NOT READY. As far as I can remember, in NY for your model year you have at least one NOT READY allowed to get the sticker. [This was EPA rule, you might want to double check it] It will take "a while" for all of them to go ready. The last three to go ready will be EGR / CAT / EVAP. Usually if you drive on a highway after the car is at operating temperature, AND let it coast for 10 seconds after it reaches 60 mph, at least the two of the three will go ready (assuming you have fixed the underlying problem). After replacing the O2 sensor, drive and see if the CEL goes out on its own. If so, verify that no more than 1 monitor is NOT READY and take it for the inspection. Given that you own the Autel, you should be able to time it right to get the sticker. Don't you now think it is the best investment you made ? :-) By the way, when you get the O2 heater code, usually replacing the O2 sensor will fix it but you should still rule out possibility of wiring faults and/or bad connection. You can test for that and/or use contact cleaner for the connection before replacing the sensor. - Vikas
 
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Messages
25,135
Location
MA, Mittelfranken.de
Quote:
if I'm throwing a P0141 code (related to the O2 sensor) wouldn't the O2S show up as Not Ready as well? I'm assuming that the faulty O2 sensor is not letting the system monitor the converter properly
The O2 was working.The heater part of the sensor is defective,this does not effect the units ability to monitor only to bring the system into closed loop quicker.
 

dgee

Thread starter
Messages
429
Location
Metro NY
This morning, I took my car out for a 30 minute drive. That would be sufficient for the car to fully warm up. After I got back home, I hooked up the Autel scanner and checked the I/M readiness monitors. Once again the CAT monitor reads as not ready. hmmm So I plan to change the O2 sensor on Saturday. After the work is done I should just drive it without clearing the code in hopes that the CEL will go away on its own?? I want to get the car inspected the same day so I need my I/M monitors to be ready.
 
Messages
11,660
Location
NorthEast
If you reset it, then there is no way you will get all monitors ready on that day. On many vehicles, there is a specific sequence of monitors to run. Some gets deferred if you get a CEL. CAT monitor is probably one of them. Good news is that O2 sensor code should clear on its own very quickly (this is my assumption) because ECM should be able to determine if the heater is working or not without any extensive drive cycle. Do you plan to do the work yourself or give it to a shop? If you give it to a shop, you will have to specifically tell them multiple times NOT to reset the light. Keep that Autel in the glove box so you can check the codes and I/M readiness monitors on the road. Anyway, as soon as light go out on its own, you can take it to get inspected even with the CAT not ready AS LONG AS THAT IS THE ONLY NOT READY and you have no CEL. Don't go for inspection to pick up a rejection sticker. That will be BAD NEWS because then the state forces you to get CAT ready along with the other monitors i.e. you can NOT have the CAT as your freebie. You can still have one freebie but it can NOT be the CAT. I never understood the rationale for having different criteria for initial inspection vs the re-inspection but those are the rules. Work them in your favor instead of against you. - Vikas
 
Messages
1,027
Location
Wisconsin
I have a 2003 Sienna and the post catalytic converter sensor may be set up similar to yours. If you go under the vehicle, and the sensor wires go up through the floor, then don't panic. In my Sienna, I only needed to remove the trim panel that is at the base of the passenger seat.....driver's side of the seat. At the front of the seat.....just under the seat, is where the sensor wires plug in. You unplug it.....push it down through the floor, grommet at all. My replacement sensor came with a new grommet. Now, getting the old sensor out of the rusty exhaust pipe could be a challenge. I was unlucky enough to find that one of the studs for the sensor was missing already. Plug location at base of passenger seat.....front left side.
 
Messages
8,439
Location
Texas
The PCM knows that the 02 sensor past the cat is bad so that test is not running. Once you replace that sensor and the car sees it as good, the readiness tests will complete.
 
Messages
11,660
Location
NorthEast
Looks like CT does not tell you about the number of "freebie" I/M monitors allowed based on the model years although it does tell you about needing CAT for the retest. I suspect CT has the same rules as EPA or any other states. - Vikas
 
Messages
1,087
Location
Minneapolis
+1 for not having driven it enough. Research what kinds of scenarios the ECU is looking for to set readiness. It can be elaborate and take a few days of driving.
 
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