My Tacoma just failed state emissions test - Please Help!

My fuel level is always at least 1/2 tank full. I did not know that could effect emissions inspection

 

You can’t trick the machine it get plugged in and reads the ecu, if the monitors haven’t run or the code has a dtc currently present you fail. Has nothing to do with the guy doing the test.

 

So the machines never fail?

 

So emissions monitors will only run between 1/4 tank of fuel and 3/4 tank of fuel. There is a preset list of driving circumstances that need to be fulfilled to achieve an emission drive cycle which will run the emissions monitors.

 

you could try idling at 2500 RPM in park for 2 minutes. I had to do that a year ago with a Benz to get the drive cycle to update.

 

The machines either work or they don’t which means they can plug it in and do the test or not.

 

Interesting.

 

Just take it for a good drive this weekend and see if it passes. No one on here can tell you for sure why it reset, or even if it really did reset.

I wouldn't worry until it happens again.

 

Could someone have flashed your truck while you were in the dollar store?

All joking aside, what @whatstcp said. Just drive it around for a week, and go back. If it does it again, then perhaps your battery is compromised, causing your ECU to lose memory.

 

Ok I will try driving it 100 miles and see what happens - Inspection station told me its probably going to fail because something is clearing codes - report read - Miles since code clearing =2 which he said meant battery was disconnected or codes were erased. I dont know how to erase codes and truck has original battery - never disconnected

Hope driving it works - I will find out in 3 days - Thanks to all

 

Thanks - I will also check battery - that I know how to do with a meter. Also I will check with truck running - alternator charging battery

 

In PA, emissions are required every year in the metro areas like SE PA.

 

I feel like that's a German or European thing. I think on VW you can force a drive cycle in the bay as well.

 

It's probably realistically like 10-15 miles in some cases. 100 miles is just boilerplate to ensure its actually done.

 

If you're on a 4 year old OEM battery, chances are it's toast.

 

TO TIM COO2 - WROTE
So emissions monitors will only run between 1/4 tank of fuel and 3/4 tank of fuel. There is a preset list of driving circumstances that need to be fulfilled to achieve an emission drive cycle which will run the emissions monitors.

I JUST FILLED MY GAS TANK RIGHT BEFORE THE EMISSIONS TEST - I DID NOT KNOW THIS - THANKS

 

Even for new vehicles though? I just meant that over here you don't have to start getting tested until the vehicle is 8 years old (then you go in every other year for a test).

It seems weird they'd require emissions testing annually on brand new vehicles

 

It doesn’t matter for the actual test. It’s for the monitors to run, typically monitors will stay completed once they’ve run unless the vehicle sits for extended periods of time without being driven or battery disconnected or codes cleared.

 

Texas starts on the 2nd year of new car ownership, then it's annually thereafter.

They give you a pass on the 1st.

 

If you have a ScanGauge, you can check the readiness monitors as part of the scanning. When I was chasing a CEL in my C5 right around inspection time I was using my ScanGauge from my truck to check readiness.