If you disconnect the battery, doesn't that reset fuel trims to zero? Would there be any advantage to doing that, and then see how quickly and in what direction the fuel trims adjust themselves? You might be able to acquire good data more quickly than just driving and letting the trims slowly adjust.

I know this would also clear any monitors, but since they are presently not all setting properly, you're not losing anything.

Still wondering what would happen if you tried a different scan tool, too. Just thinking out loud if it's really an interface problem.

 

And boom On come my check engine light.....

again......

 

I believe after everything from smoke tests to carb cleaner with no luck. I seemed to have found that the PCV valve is stuck open. Hoping cleaning or replacing that solves it.

 

I thought the same thing on mine. So I bought a new valve and it was also open like the one that was on it. I have no idea how they’re supposed to work. Theres a spring in there that closes it on a backfire but its always open on mine. In fact made so little sense to me that the brand new one was exactly the same as the one I took off (and I tested them on the bench and they were exactly the same) That I cut the old one open so I could try to figure out what it was supposed to do and that’s when I realized they’re open at idle. The only thing I can come up with is that the engine relies on all the other O-rings and gaskets and oil cap, etc to seal the engine from outside air that it doesn’t matter that it’s open at idle because airflow through that valve is restricted due to all the other seals preventing air entry points into the block

 

After spending almost a year now trying to get this o2 sensor emission ready for smog. I am still at loss. I have called two highly rated Jag mechanic shops and explained the situation. Both are lost and said there's nothing they can do. My last resort is to send the ECU in to get inspected and tested as I can't possibly think of anything else that could be causing that. Who would of thought this would be so hard to get the damn car street legal.

 

Sorry to hear your still fighting this!
As you posted above have your fuel trims settled down or are they still as high as they were?

Also not much help but where I live you are allowed to have 1 readiness monitor not set and still pass. Have you had them at least try to pass you?
How many monitors are ready and how many or still NOT ready?
.
.
.

 

I am in California so all the emissions have to be ready sadly. All the monitors are ready except the O2 sensors. Fuel trims are around 5 and 7 which is a little high, but typically go down a little and are not creating any leans codes as they use to a lot a few years ago before I did a lot of vacuum leak services.

I have done multiple drive cycles, resetting the ECU, hard reset by unplugging the battery. I can get all the emissions to pass in literally 20 miles or less. But when it comes to O2 sensors. I got the car up to 700 miles once on a cycle and it was still pending. There has to be something broken. The cats which are usually the hardest to pass will pass in around 10 miles with the drive cycle no problem. But that 02 sensor monitor is still lingering. I called 2 Jag mechanics and offered to pay them to look at it and both said if I bring it in, there is nothing they can do about it. Such a strange problem.

 

This https://californiainform.com/advices...lifornia-2018/
says you can have one not ready. Is it wrong?

If it is, I'd be tempted to replace any upstream O2 sensor not already changed and hope.

 

That is correct. But on my year and up the only single one that can be not ready is the evap. All others need to be ready.

 

If you now have good fuel trims, see post #68.

 

Yeah, I guess the next path is to put some bosch upstream sensors in and see if that makes a difference.

 

Just hopping on this thread. My O2 sensors are not setting (unusual) but I'm contending with a P0171 (vacuum leak) found it at the brake booster connector at the throttle body.

If I'm not mistaking certain sensor readiness will not initiate if there are outstanding issue(s) hence O2 sensors if there is a vacuum leak(s) wacking out the LTFT and STFT's...

 

I had an o2 sensot not set for my first smog on my 06 str and tried these and it worked until i had the money to fix it properly. Might be worth a try. Ebay item 254359183203. Check it out. Or something similar from here in the US

 

Hello I'm just checking to see if there was ever a resolve to the issue of the o2 sensor not ready?
I have a 06 STR with a similar issue
Thank you

 

no the owner gave up and probably sold the car. if you have a monitor problem and can’t pass smog go to uhaul.com

 

Thank you for letting me know how the story ends
Helps to know ugh

 

What are the fuel trims (as so may posts explain how to measure)?

 

Hi got it thanks: The STR is new to me so my first step here is to see if my existing OBD readers will work or find a new one that will pull more data other than basic codes. Then I’ll check