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MalcolmV
08-15-2014, 04:32 PM
Went for a Drive Clean test the other day.
Got a conditional pass. :frown:

I had driven the car for about 35 Km before heading over for the test to ensure things were nice and warm.
However the Catalyst and Oxygen Sensor reported NOT READY.

This is good for 2 years ... but any idea of what the cause could be and how to correct?

Mods to the car:
Replaced up-pipe with catless up-pipe
Tune by Innovative Tuning

MalcolmV

wparsons
08-15-2014, 07:28 PM
Not ready means whatever driving you did didn't meet the conditions for the sensors to be in a ready state. The drive clean site has a suggested drive cycle to do with the car that should get all the sensors ready, but some of them are impossible with a manual (put it in park, and hold it in place with the brake, etc).

You might also want to check with your tuner to see if there's any limitations with the tune and sensors, but I imagine that should be fine.

STeveD
08-16-2014, 04:44 PM
Did they tell you if it was the front or rear oxygen sensor not ready?

Might be you're due for a new front sensor, or if it's a rear sensor, maybe Mike can just alter the parameters.

wparsons
08-16-2014, 06:14 PM
If it's not reporting as ready, it won't even attempt to trip a CEL. Unless the sensor is totally dead, it should still report ready once the drive conditions are met.

My wife's bone stock Camry failed on three sensors not ready, took it for a rip (as much of a rip as one can do in a Camry :D ) on the highway, took it back the next day and it passed 100% cleanly.

STeveD
08-16-2014, 09:47 PM
Look for black electrical tape over your CEL. ;)

I've done the same with my father-in-law's Camry in the past, but now he has a CEL for heater circuit failure. Low km, but 13 years old.

MalcolmV
08-21-2014, 09:32 AM
Thanks Guys, I'll look into replacing the front O2 sensor.
Hope for the best for the Catalyst next time!

wparsons
08-21-2014, 11:20 AM
I wouldn't replace the sensor unless you're actually throwing a code for it (or it tests bad otherwise).

Not ready does not mean the sensor is bad, it means the car hasn't been driven the right combination of cycles for the ECU to trust the sensor reading.

7plymaple
08-22-2014, 01:21 AM
I wouldn't replace the sensor unless you're actually throwing a code for it (or it tests bad otherwise).

Not ready does not mean the sensor is bad, it means the car hasn't been driven the right combination of cycles for the ECU to trust the sensor reading.

This is my understanding of it. I didnt think "not ready" was a reason to get a conditional pass. I put about 130km on my car after changing my cat and resetting the computer. Was going on the advice that the car needed to be driven for a week to be sure it wouldnt give the not ready reading. Then ended up with a similar situation with my girlfriends car but her cel was from a leak in the exhaust (Of course it had to happen right before we had to e-test it). Fixed that on a friday night and put about 120-140km on it driving around for the weekend. It passed on the monday morning.

Anyways maybe 35km just isnt enough driving for thr computer to check all the boxes and the guy testing couldnt be bothered to tell you to go for a drive? Or is not ready a reading that faulty sensors give?

wparsons
08-22-2014, 09:42 AM
Not ready means the ECU isn't accepting the reading based on the recent drive cycles. If the sensor is not ready, it will not throw a code (because the ECU doesn't trust it). That's the reason the new test checks for a valid ready state and stored codes. If it didn't check for ready state, you could just reset the ECU in the parking lot and it wouldn't have any codes stored.

You can absolutely get a conditional pass because of sensors not ready. The condition is that when you come back for the re-test (minimum of 24 hours after the original test) you have the same number, or less, sensors not ready as the original test.

Like I said above, my wife's Camry had three sensors not ready (at the time she was driving < 5km each way to work, so the car was never getting fully warmed up). After it failed on the sensors not ready I took it for a couple WOT pulls on the 407, and came home. Probably drove about 20km's total once it was warmed up. Took it back the next day and it passed with every sensor ready, and no codes stored.

The drive clean website used to have a full list of a good drive cycle that should get everything ready, but I can't find it anymore on their new site.

https://www.ontario.ca/driving-and-roads/how-do-i-get-my-vehicle-ready-drive-clean-re-test

The test centers also had brochures about a year and a half ago, not sure if they still do or not.

Loopy
08-22-2014, 10:43 AM
Didn't you put a resistor when you did your cat-less uppipe? or did the tune take care of that? Is the front sensor still there? or did you replace it with a bolt and washer?

MalcolmV
08-25-2014, 08:20 AM
Hey Loui, yes resistor was put in and is still there. Resistor was done prior to tune and I believe also the tune took care of that. I have to email Mike @ Innovate just to be sure.

Thanks for asking!