How to replace the outside door handle of honda accord 98. and why is my engine light coming on and at the same time my speedometer not working

You will need a repair manual. It involves removing the inside
door trim panel, a job in itself, the watershield and so forth
to access the outside door handle and mounting bolts.

In all probabilty, the metal rod that runs from the outside handle down to the locking mechanism has become dislodged. This same rod also operates the inside door handle. Either that, or one of the plastic connecting levers to the same rod has broken. For this repair you will have to dismount the inside panel of the door. Search in this site for the steps to disassembling the panel. I think i wrote about it once.

The cable going to must have come undone or handle leaver inside is broken. The interior door panel will have to be removed to verify problem.

You need to replace the vehicle speed sensor located on the trasmission.

check the speed sensor,if the computer doesn't know the speed it does not know how fast you are going ,so you won;t have peak performance

the speedo could be the sensor on the gearbox the lights not working could be the bulbs have blown

I had the same problem on 1991 Honda Accord! It was the old AT fluid. I changed the fluid and all problems vanished! I had asked a Honda mechanic at first problem and he said make sure the AT fluid is good! Happy Honda Owner

Did you check the dimmer to switch? This is for a 2000 Honda Accord but this may help you: If your instrument lights have burnt out on your 2000 Honda Accord.... You may have another problem!!! While the dealer fixes this recall, they should replace your burnt out bulbs. 2000 Honda Accord Recall ID from NHTSA: 04V256000 Auto Recall Date: 06/07/2004 Vehicle Component: INTERIOR LIGHTING Estimated Vehicles Affected: 19572 2000 Honda Accord Defect Summary: ON CERTAIN PASSENGER VEHICLES, THE DIMMER CONTROL FOR THE INSTRUMENT PANEL LIGHTS COULD FAIL DUE TO HEAT BUILDUP. Defect Consequence: IF THIS OCCURS, THE INSTRUMENT LIGHTS MAY FAIL AND, AT NIGHT, THE DRIVER MAY NOT BE ABLE TO SEE THE INSTRUMENT PANEL GAUGES, SUCH AS THE SPEEDOMETER. Remedy: DEALERS WILL REPLACE A MULTIPLEX CONTROL UNIT FOR THE INSTRUMENT PANEL LIGHTS. OWNER NOTIFICATION BEGAN JUNE 16, 2004. OWNERS SHOULD CONTACT HONDA AT 1-800-999-1009. Notes: AMERICAN HONDA MOTOR CO., P36

A green flashing "S" is similar to a check engine light. It is telling you that something in or on your transmission is not functioning correctly, such as the speed sensor or shift control solenoids. If it starts flashing and the speedometer stops working or the transmission shifts weird, take it to a mechanic.