Lesson learned: Don't unhook your battery if you're going to get your car smogged anytime soon. That's what I did last week when I replaced the front valve cover gasket. The service manual said "disconnect battery" as the very first step. I went ahead and did that so as to not put the computer at risk while doing repairs. So now I have to put the car into an unknown number of drive cycles before the car will be ready for a smog test. The smog tech said the computer needs time to build a history from the reports it receives from the post catalytic oxygen sensor. Right now I'm left wondering if some kind of scanner would've told me whether or not the car was ready for testing. $39.75 out the window.
Smog Tests
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Drive 50 miles. Around here the retest is at a reduced rate. Good luck.
The same think happened to me on my Tundra. No biggie.
They do this so people don't clear the trouble codes just before a smog test.
The same think happened to me on my Tundra. No biggie.
They do this so people don't clear the trouble codes just before a smog test.
What risk would you put the computer in by changing the valve cover gasket? They just put that line in for liability reasons on nearly any procedure in case some idiot does something stupid like lay a crowbar on top of the battery while changing the hood supports. Unless working on something directly connected to the battery like the starter or alternator, I don't disconnect it. Not even when removing an airbag.
Yes any scanner that will read your make and model will report the readiness
Even better the I/M monitors are part of the generic OBD-II protocol so any scanner capable of monitors will know.
I had to disconnect the electrical cable going to the alternator because it ran across the valve cover.
People used to clear a code then run to the smog place before it came back on. Now the first thing they do is test the monitors. If they are not set you fail.
If a GM vehicle, then EVAP tests will not run unless gas tank is between 1/4 and 3/4 of a tank and an over 45 mph cruise cycle is needed.
Every mfg. has specific conditions for I/M monitors to run their readiness self-tests.
Every mfg. has specific conditions for I/M monitors to run their readiness self-tests.
USED to? Still do. Just have to make sure the required monitors are set before the CEL comes back on. Actually it feels like you got something over on them. Quite satisfying.
In that case, I'll run the car up and down the freeway for the next two days and then go back to the smog shop on Friday.
In the meantime, order this:
and be prepared for whatever might pop up in the future. Won't debug all possible issues but will help you be prepared for at least the first level of diagnosis in the future.
It probably takes a cold start (at least 8 hours) and probably has to be within a certain ambient. Having the Air Conditioning on might also stop it form running.
Google "Drive Cycle" for your make and model.
Also depending on the year you may be able to pass with one or two not ready, check your states smog site.
Yes and once it's started don't turn it off for a while. I had a customer that would start his car then shut it off to open his gate. We couldn't figure out why it would not set it's monitors.
In the 60 years I have worked on cars, I have never disconnected the battery. If I'm working on a part of the car that needs electoral disconnected, I pull the fuses to that part of the car. Never had a problem. And that includes replacing air bag modules.
What a jerk. Most places check the readiness for free before even hooking up the main machine
In California it's law that they can't check stuff for free. If a car comes in and the smog guy knows it's going to fail he has to fail it. Can't tell the customer it's going to fail.
Yeah they will flunk you around here for not ready... but you get one free retest in 30 days - actually that was in GA around here they don't test...
All the places I have been ask if you have disconnected the battery lately. The place I regularly go checks with a cheap code scanner in the parking area before even pulling it in. Technically the test hasn't started. Same with air intake, if it doesnt have the CARB decal, they wont even bother starting the test at most places.Guess I just live in a friendly area.
I'd assume that's a courtesy & the tech probably values their time (and sanity) from dealing with Karens each time it happens. I know I'd ask that question if I was a tech
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