Yeah, Mass uses code scanners. If you clear an error or loose your 'ready' code due to a dead battery, you will need to drive it, until it comes ready.
Most scanners will say "Ready for Inspection"..
The SG2 has this message:
Echo Error code P0171
My sister-in-law had a problem with her 2000 Echo and didn't want to bug me and took it to a gas station garage.
The error code P0171 (too lean) was found and the shop changed her O2 sensors. $$$$
The check engine light comes back on a week later and the guy is stumped. He resets the code.
Since the car needs inspection in July, and the check engine light is on about half the time and the engine has been running rough and is hard to start when cold etc, she breaks down and comes to me. (Since I told her I have a scan gauge now)!
I read the Obd code P0171 (too lean) and look it up on the web.
In about 20 seconds I found out that the most likely problem is dirty sensor
wires in the MAF sensor. One website even shows before and after pics of the wires.
I pulled the MAP sensor off (two screws) and sure nuff, it was gummed up just like in the pics!
One of my cans of spray stuff said 'Starting fluid'. I checked it out and it worked like a cleaner on some junk parts. Didn't melt rubber, so I sprayed the sensor wires until they looked like new.
After 50 trouble free miles, she passed inspection and reported that her old Echo is running like when it was new. It had been stalling when taking off. Plus, she got 47 MPG on her last tank..
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Just lately, I found out her 'mechanic' had also changed her fuel pump in the spring. (I don't know why).
But, she has just had two new cases of the engine check light coming on.
Both times, she had just got gas at a full service station.
I checked her code and the error info was a little fuzzy. I think the gas over-fill sensor in the fill-hose is kicking on. Plus, all the gas stains on the side of the car was a clue..
I've found out the Echo is one sensitive little bug.. It will drop an error code at the drop of a hat.
Some owners get so many emissions codes, they just learned to ignore the light and keep on driving..