I had P1126 (Thermostat) come up while my car sat through most of the winter. I reset the light and no CEL for over 2 months. Its a 01 with Hotshot headers. Running a O2 sim for the secondary's. Haven't had a CEL since having owned the car a little over a year. The issue im having is I have to pass emissions and cant seem to complete the O2 drive cycle (readiness for inspection).

Its been over two months since I reset the light. When i hook up my scanner, no codes come up. Every other monitor is complete except the the "oxygen sensor." I have completed the series of steps that are in the owners manual(10-21) that shows how to get it ready and cant clear the readiness cycle for the O2. It keeps reading as incomlpete. Would this be an issue with the O2 simulator? Those who are using simulators, how long has it taken for a drivce cycle to complete?

Can someone with a consult be able to complete the readiness cycle that the ecu goes through? Looking for suggestions as I am overdue for emissions.

I know the only logical thing would be to keep driving the car and I have done so for the last 2 months. Both long trips and short trips.

 

What are you using for sim? Is it one of the cheap 555 based timer ones? You might want to try one of the newer ones if it is.

 

I'm using the simulators that were sold through O2simulator.com. They are at least 4 years old at this point.

 

I just went in to get my state inspection done today at lunch. It failed because both monitors were not ready. I haven't had an emissions related code on the car in several years, and the last time I had the battery unhooked was Dec 08, when I replaced the starter.

Not trying to threadjack, I'm in the same boat as you, can't pass emissions, but no stored/pending codes. I however don't have any exhaust mods, so I know its not a bad o2 sim or anything.

I'm going to hook up my dads scanner tonight and see if I can reset the monitors and try again in a week or so.

Anyone have any other ideas on what to look for?

 

Anyone with any ideas on why our monitor tests are not completing?

I have 11 days to get it running and re-tested before I have to pay another 28$ for the test, which I really would like to avoid.
Mine are the Catalyst, and o2 sensor testsl

 

holy hell i am having the same problem!! anyone got a clue on this?

 

Anyone?

 

For many states, 2000 and earlier model year cars can have up to 2 monitors not ready and still pass the inspection.

Here is a *great* site which gives lots and lots of information about OBD.

OBDII Overview
OBDII: A Quick Review............................................ ........................2
Setting Readiness to Pass the OBD Test........................................3
Don’t Turn That Light Off! .................................................. ..............5
Readiness Monitors
Setting Monitors that Defy Standard Methods ................................6
Stubborn Monitors.......................................... .................................6
OBDII Readiness Case Study .................................................. .......7
The Unexpected is Just a Little Tougher to Fix................................8
Five-Time Reject – A Case Study............................................. .......9
ALL Enabling Criteria Must Be Present to
Run Monitors.......................................... ......................................9
Meeting the Enabling Criteria is Crucial ........................................10
Driving Isn’t Always the Fix after Eight Rejects ............................. 11
How Fast Am I Going?............................................ ....................... 11
Tough-to-Run Monitors can be a Simple Fix .................................12

http://www.epa.state.il.us/air/vim/p...-review-08.pdf

- Vikas

 

we don't need to know WHAT monitors are failing. we are clearly aware of that. we want to know WHY they are not setting.

 

I had the same problem with my o2 sim!

The readiness monitor would not set and then after 300 miles it set and it also popped up 2 codes. p1147, p1167.

Please let me know what happens.

 

Well last night I completed the drive cycle from the owners manual. This morning when I checked it seems my catalyst monitor is ready, but the o2 monitors are not. But, the guy told me I can pass inspections with one monitor not ready, just not with two. So hopefully I will make it back there tomorrow or sat to get my sticker, before it resets itself again or something.

That drive cycle is pretty long and tedious. I don't see how someone could do it without a long empty road to run down the whole list on. I have a toll road by my house that nobody uses, so I completed the whole test in one long drive, all in order. Took about 30 minutes, and I drove about 25miles.

If you haven't done so I would suggest doing the drive cycle again. If possible do it in order, in one long drive.

 

Yea, you definately need a long road. I had to do mine on the highway late night to make sure I had no traffic to stop me from doing the steps. I'll have to look into it and maybe I will be able to pass with one monitor not ready.

 

The trouble is you need the manufacturer's data to find exactly what is the definition of a drive cycle for each of the monitor.

When the car is on the borderline, you are fighting to get all readiness monitors set before it throws a check engine light. The person who said he will take the car in later during the week, should reconsider. There are quite few examples where instead of getting the last readiness monitor set, you get the check engine light.

- Vikas

 

For that you need to get the list of "enable criteria" for running the monitors. This is specified by the manufacturer. The reference document that I had linked in provides many examples. There was a case where the temp sensor was giving bad data and thus ECM never started the specific monitor because it could only run when it believes the car is hot enough. Many of the monitors are interdependent. If ECM is not getting its keep-alive power, your monitors will keep on resetting every time you turn off the car.

I know on my 2000 Maxima, it took at least a week before all the monitors were ready but since I knew that I could pass the inspection with couple not ready, I went in for inspection as soon I had all but two ready.

- Vikas

 

Some useful info Vikas. Thanks.

I just looked through the site and it appears i might be able to pass with one monitor not ready. I called the "Air Team" but lady over the phone was being very difficult so I coulndt get my answer.

 

I just went and passed inspection! The catalyst monitor was ready after completing the drive cycle in sequence, in one long drive the other night.

The o2 monitor was still not ready, but he said I could have one still not ready and pass. So until I throw a code, I'm not worried about the o2 sensors.