2016 Kia Rio
Mileage
104,880
Service Date
5/8/2026
Services Performed
- Retrieve codes and diagnose possible misfire. Codes on the memory are P0300 Random cylinder misfire, P0303 misfire cylinder #3. P0304 misfire cylinder #4. Cylinders #3, and #4 have spark. Spark plugs are fouled and compression is low. Cylinder # 1 fist puff 40 psi total 110 psi " # 2 " " 40 psi " 90 psi "" " # 3 40 psi 150 psi #4 40 psi 70 psi Plugs were over torqued, and they are fouled . First puff is too low indicating worn rings. This vehicle has a GDI system and probably has a lot of carbon build up. Plug # 3 is oil fouled. Doing a GDI fuel injection cleaning will remove a lot of the carbon build up and may restore the compression problem this is something that should have been done a while back, and plugs should be replaced.
- SPARK PLUGS – Remove & Replace – All
- Perform visual inspection of the fuel system, check for DTCs, road test vehicle, be aware that carbon build up on this vehicles will cause misfires and may need more diagnostics and work. PERFORM GDI INJECTION SERVICE USING A 4 PART BG GDI KIT, clear DTCs that may set do to the service, and road test the vehicle.
Charles S. gave our service a 5 star review on 5/14/2026
