My check engine light came on for the first time today. I hadn't used the car at all yesterday, then I go out to run some errands today, and first I get a message in the DIC to tighten my gas cap (stopped the car and checked it, but it looked fine), and then I noticed the check engine light was on.

I don't have a code reader now. If I wanted to get one to find out why the check engine light is on, is there any special type needed for my 2006?

 

Doesn't autozone still do it for free?

Also, you say the gas cap looked fine- did you try removing and reinstalling it?

 

Yes, I did remove and reinstall the gas cap when I stopped; I should have said that before.

I hadn't thought about Autozone being able to check for codes. I'll have to look into that. They did check my battery and alternator for free a few weeks ago.

 

So I took the car down to Auto Zone yesterday on my way to work to have them pull the codes and tell me why my check engine light is on.

The guy hooks up his his code reader to the connector under the steering column, and can't get any codes at all. There was nothing displayed on the code reader. He tells me that he knows the reader is working OK because he just checked someone else's car about a half hour ago and it worked fine. Then he tells me I need to take my car to a mechanic to have him read the codes from under the hood.

Why wouldn't the OBDII connector inside my car be working? Maybe the guy at Auto Zone was using the wrong type of reader for my car?

 

You could try a different auto parts store before heading to a mechanic/dealer; they may charge you just to hook up their code reader. I use Advance Auto for code reads around here.

 

Any ODB-II scan tool should be able to read the codes in your car. The problem may be the condition that currently has you Check Engine light on may not be currently occurring, but if the light is on, it's in the code history (previously thrown codes). To my knowledge, there is no tool to scan codes from under the hood.

I'm with Sparky, go to another parts store. In general, most my experience with AutoZone is they don't hire the best people to run the place and have REALLY high turn over (so odds are, the people there today will be gone in a week and never really learned how to use the test equipment there).

 

That doesn't sound right...I would lean toward the guys code reader or operator making an error.

 

My local Advance Auto Parts store said that if I wanted to read the codes on my car, I could come in and give them my driver's license, and they'd give me a code reader to use. I didn't like the idea of giving my DL to a complete stranger.... too much info there that could be used for identity theft. I know it sounds like I'm being paranoid, but better safe than sorry.

The other option was to take the Monte over to Aamco transmissions; they'll diagnose a check engine light for free also, but I figured they'd just tell me something was wrong with my tranny to try to sell me a new one.

So, I ordered my own code reader from Walmart.com. This way I'll be able to read my own codes if the light comes on again in the future. I should get it in a couple of days.

 

So I finally got the code reader I ordered from Walmart.com, read the codes and got a P0449 code (EVAP vent solenoid control circuit malfunction) and a P0455 code (EVAP system gross leak detected).

Has anybody else ever had these codes come up on their Monte? What needs to be done to fix the problems?

 

I believe one of your two codes my friend's '97 GP got. You're drive train is different then his, but the problem might be the same. I found some badly dry rotted vaccum line fittings. Replaced them, cleared the code and now for months, no problem.

I would recommend inspecting for any vaccum leaks. Should not be too many lines, but worth inspecting and probably a cheap fix.