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billyboblyons · Nov 2, 2007, 05:58 AM

Still having Check engine light problems. Changed o2 sensors, plugs, wires, ignition coils, pcv valve and fuel filter. The code that keeps coming up is 0422. Help. 99 Kia Sephia. Car runs like crap. Like id would with a bad o2 sensor.

CaptainRich · Nov 2, 2007, 06:00 AM

Originally Posted by billyboblyons

Still having Check engine light problems. Changed o2 sensors, plugs, wires, ignition coils, pcv valve and fuel filter. The code that keeps coming up is 0422. Help.

Year make and model please...

CaptainRich · Nov 2, 2007, 06:03 AM

That code on most vehicles is related to catalyst efficiancy, not drivability directly.
**edit** Is that the only code you have been getting?

billyboblyons · Nov 2, 2007, 06:11 AM

Sorry. 99 kia sephia. Yes, only code 0422 . The car still runs like crap.

CaptainRich · Nov 2, 2007, 06:22 AM

OK, let's back the bus up and start with the rough run. You've done the secondary ignition system.
Have you had the fuel injectors professionally cleaned? Not the cute little bottle that goes into the tank. That stuff only cleans wallets. I'm talking about the stuff the pro's attach directly to the fuel rail while disabling the fuel pump... You may have an injector sticking open and dribbling instead of spraying.
You could also have build up on the valves (esp the intake valves because they don't run as hot) that can cause problems. The build up acts like sponges and soaks up fuel until full and then releases it uncontrolled.
Try using a product like GM Top Engine Cleaner, or the like. Follow the instructions and see if there is any improvement.