2005 Kia Rio keeps on throwing check engine light with speed code error code. Dealer replaced plugs, wires, rotor cap, and speed sensor on transmission. The light still comes on. When gas peddle is stepped on hard, engine rev but trany doesnt shift. Can any one help define the problem and/or solution?

The belt tensioner is defective. It automatically keeps the belt at the proper tension. P0101 - MAF sensor (mass air flow sensor) or circuit problem. P0107 - MAP sensor (manifold absolute pressure sensor) signal is low.

To begin with, is your "check engine (CE)" light on? If it was on and now its not, you need to replace the bulb. If CE lights is on, find out the codes before doing anything. If bulb is good and "CE" does not come on, begin with: (1) gapping spark plugs, (2) replace spark plug wires (if haven't changed them within the last 2), then the coil. If your Cinco is still idles rough, adjust gas pedal until idling smoothly. If this still doesn't help, replace your two oxygen sensors. If still running rough, the converter. After doing all this and problem is still present, take it to a mechanic you trust.

Check the wiring, animals love chewing on wires.

What gasoline rating is the octane?

Hi there:

A code P0302 may mean that one or more of the following has happened:

• Faulty spark plug or wire
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector
• Burned exhaust valve
• Faulty catalytic converter(s)
• Running out of fuel
• Poor compression
• Defective computer

Possible solutions:
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.

If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

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Change BOTH oxygen sensors. Remove cables from battery to clear codes.

get the timing checked again its a couple of teeth out thats for sure iam 99% positive on this

CODE PO501 VECHICLE SPEED SENSOR PERFORMANCE.POSSIBLE CAUSE IS FAULTY VECHICLE SPEED SENSOR.CHECK SENSOR WIRES AND CONNECTOR FOR DISCONNECTION OR DAMAGE.

P0304 code is a cylinder 4 misfire. If the plugs or wires are bad it will cause a decrease in power. I suggest changing the plugs and wires and see if that helps.

I'm guessing it was a misfire code. Lack of fuel will also cause a misfire code too, were you aware of that?