Service engine soon light came on today why - 1999 Dodge Caravan

If you know the plugs are fine then an ignition wire or a coil will cause the same symptom . If you had a code reader it would show you which cylinder is causing the miss. Beyond that a compresion test is needed.

You have a real auto repair shop ( not auto parts store) look at stored codes, & any freeze frame data
Do not clear the dash light or you loose data & ability
to diagnose & resolve the issue

all part stores will scan the car for free and I need the codes please

I have a 1999 Mercury tracer. I was driving down the highway two weeks ago and my check engine light came on. i went to autozone and he said something about misfire on bank and vacuum leak. He said it bascially was a tune up. i got in my car the next day and the light went off. it didnt come back on. Last sunday i got a tune up and a oil change. i was driving to work today when my service engine soon light came back on. could it be because its been warm here in st louis and all of a sudden its cold. or do i just need to get it reset. i hope its nothing major because im broke right now and cant afford to get it fixed

The Service Engine Soon is for an exhaust emissions issue and the EML is engine electronics. Could be a sensor or something else.

The service engine light is totally safe. If it's just the ABS light, it's safe as long as you don't panic stop on the way to the shop.

drop by autozone and they will scan the codes for free (at least the last time i heard it was free) the people there are fairly knowledgable so they should be able to tell you why the light is on.

sometime it's a one off that triggers the light. after three cycles of the key when it hasn't encountered the same problem it will go out.

May save yourself a fair bit of money by not guessing, autozone will scan it for free & then you should know exactly.

Plug out all the sensors at the bottom where you sprayed it down and blow out all the plugs on the inside

Does it ever go off? Or is it on as soon as you turn on the vehicle?