Q: 03 Kia Rio Cylinder 1 Misfire

asked by on November 08, 2017

03 Kia Rio 134,000 miles

I recently bought a Kia Rio and it had a check engine light. When I found out it was a Cylinder 1 misfire code I religiously looked through every forum I could find and started replacing the most common problems so it would be a reliable daily driver. The engine runs and drives. And it dosnt misfire all the time. It will show check engine light for about 5 miles then turn off and then come back on ect and then looses acceration and the code shows up. By new I mean brand new not junkyard parts. This is what I have done:

new 4 spark plugs new spark wire set new coil pack new fuel injection rail new 4 fuel injector jets reset ECU computer

Taped all cables and wires with extra electrical tape for safe keeping and cleaned all grease off most parts. These all seem to help alot but I still occasionally lose power.

Next I checked the timing belt and it seems like it could be a problem because the case has a little damage inside and the white arrows don't lineup

My car has 130000 miles.
My car has an automatic transmission.

Timing Belt Replacement $295.56 - $1425.61 Get a Quote

Hi Kegan. Thanks for contacting us tonight. It certainly appears you have done a great job trying to diagnose this random misfire. The fact that there is slight damage inside the timing belt cover and that the marks are not properly aligned would be my assumption of the misfire. The correct solution, in this case, would be to replace the timing belt, the tensioner, and the water pump at the same time. You can find out what we recommend replacing for this service by clicking this link. If you’d like one of our professional mechanics to come to your location to do this for you, you can book an appointment from that page.

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