My check engine light is on sometimes when I come out to start the car in the morning but it goes out when I start the car. Anyone have such a problem? What can cause this?

When you turn the key to "on" (not start) ALL the warning lights come on. This is the lamp test feature that all cars have, so you can make sure all the warning lights are working. Then when you start the car they all go out (hopefully).

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

yes, all lights come on and then all go out when the engine starts. It is just that the check engine light will be on when I get into the car first thing in the morning. So far it has only been on cold mornings.

With the key out?

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

I had to read it twice, but seems like thats what he/she is saying.

Strange, since this is supposed to be "dead" when the switch is off... as far I know.

What year & model car??

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the problem is not doing it now, really weird car. I would swear that there were ghosts in this thing...

We had a drastic change in the weather the other day and the check engine light was on the next morning without the key in. I unhooked the battery, replaced the ovp relay and will re-chek in the morning when cold. The strange thing is the heater motor stopped working at the same time the ce light emerged.. I had been having trouble with it anyhow in that the thing would not stop blowing but would operate on high/low. Now it is not working at all, at any speed... Any Hints?

To me, this sounds like bad contacts in the ignition switch. Like you said there was a temperature change that coincided with this problem. Perhaps the contacts are still making contact when he pulls out the key, having the light on. I've also had similar problems with me heater and key. it was cold one morning, and I started the car with a stiff key it started and the starter dis engaged well, ut the key's electrical position was not yet making contact with the 'run' connection, and I had no fan or radio till I turned the key a bit more CCW.

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