Check to see if the speedo cable came out of the tranny. There is a clip that holds it in. Pull up on the cable to be sure it's still clipped in. As far as the check engine light, look at the number of flashes on the ecu under the carpet on the passenger side. Then refer to the repair manual to see what the number of flashes mean. Or just post the number of flashes here, then somebody would be glad to tell you what the probable cause is.