Kia Troubleshooting Questions? Ask a Mechanic
replacing the battery is a good starting point
, I'd next pull out and inspect the main power fuses in the under hood fusebox as if one is corroded or cracked then this can produce intermittant power to the ECU or another control module
I'd also check that for fuel pressure as it could be a lack of fuel pressure from the electrical pump at the tank.
If the connections to the pump are corroded or damaged then the pump could stop at any time or could not be running at full speed. Check that its relay switches in and out and the relay contacts are clean and bright – replace the relay if in any doubt and do the same for the fuse,
Ideally measure the pressure at the inljectors and if this is low check the pump as described and also consider changing the fuel filter as if this partially blocked this too will reduce pressure.
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