? with Check Engine light on.

[Moonpie]

The check engine light came on in my old RAV4 this morning.
Engine starts and runs smoothly/normal.
Oil level good, Transmission fluid level normal. Coolant levels good. No noise or other external evidence of problems.
What might be some other quick and easy things to check?
I don't have a diagnostic tool so I gotta go old school until tomorrow and I can get it in to a shop.
Would a bad battery cause the check engine light to come on?

 

[baboon]

Gas cap not on tight

 

[Eastexasrick]

Easy checks for the check engine light. Loose/ worn gas cap, dirty/ restricted air filter.

 

[Moonpie]

Bad gas cap makes the check engine light come on?

 

[Eastexasrick]

Bad gas cap makes the check engine light come on?

Yes, if the fuel system is not " sealed" during operation ya throw a code, and the light comes on. Lots of other reasons, but go for the easy one first.

 

[Texasgordo]

Bad gas cap makes the check engine light come on?

Yeah I've had that happen on a 2002 Dodge Ram pickup.

 

[Texasgordo]

Maybe AutoZone can put their scanner on it and find out what is wrong

 

[dsgrey]

Battery won't cause a check engine light. Autozone or a friend should have a reader. They're inexpensive too.

 

[ZX9RCAM]

Maybe AutoZone can put their scanner on it and find out what is wrong

This....

 

[easy rider]

when was the last time you changed the oil?

 

[Moonpie]

O'Rielly was open today so I took it over there.
Their scanner said gas cap. Bought new cap.
Light still on but they told me it takes a little while to reset the sensor.

 

[Moonpie]

when was the last time you changed the oil?

about ten days ago.

 

[easy rider]

about ten days ago.

Just wondering. My Toyota engine light comes on when I need an oil change.

 

[Moonpie]

Just wondering. My Toyota engine light comes on when I need an oil change.

The oil change light in mine says MAINT REQ'D.
The light today was the check engine light.
Its good now I hope.

 

[ZX9RCAM]

O'Rielly was open today so I took it over there.
Their scanner said gas cap. Bought new cap.
Light still on but they told me it takes a little while to reset the sensor.

I think they're not supposed to reset your codes, at least that's what they told me.

If you had your own scanner, you could reset it.

 

[easy rider]

The oil change light in mine says MAINT REQ'D.
The light today was the check engine light.
Its good now I hope.

Okay, maybe I have them confused.

 

[ZX9RCAM]

My 2001 says "change oil".

 

[oldag]

I have seen a radiator cap with a slight seep trigger a code. The gas cap being loose or having a seal that has gone bad is not infrequent.

As long as the light is on steady and not flashing, it is not critical.

Pick up an OBD scanner. It will pay for itself.

 

[kbaxter60]

Gas cap not on tight

This is the first thing to check.
Our Honda threw up the "check gas cap" message about a month ago. I cranked it down and didn't see the message again . A few days later wife said "the check engine light is on". I don't have a reader, either, so I checked the cap closely and the seal looked good. The light stayed on for about three more starts, then cleared. So far, so good.

 

[Texasgordo]

My 2001 says "change oil".

Probably a good idea to change the oil filter also