I have a p0300 code the car runs fine I clear the code changed plugs and wires and the code keeps on coming back

Change wires,plugs,coils,fuel filter.

The P0300 is a general misfire code, and can be a result of numerous things. Coils, wires, plugs, injectors, sensors, mechanical issues etc. Being that you are throwing a P0316 in conjunction with the P0300, I would think that they are related, but rather than throw money at the vehicle>, do a few things first.
Replace your plug wires, chances are they are at, or close to the end of their life,Check the connector going to the CPS for corrosion or a poor connection. Clear the codes and see if the P0300 and P0316 codes come back.In the event that the codes do come back, or just one of them, you can rule out the possibility of the plugs and wires and move on to more possibilities.If the scanner you are using has the ability to monitor misfires, this could be a helpful tool to identify which cylinder(s) the misfire(s) is/are isolated to.In the event the spark plug wires don't fix your issue, and it is isolated to a specific cylinder, or group of cylinders it could tell you where to look next.

Cylinder 2 is misfiring. Spark plug could be faulty or spark plug wire could have broke internally if you didn't replace them at the same time. Swap cylinder 1 and 2s spark plugs clear code and drive again. If Same code comes back plug is good look at wire if code p0301 come up the spark plug is no good

could be your map sensor if equipped
engine timing could be of

P0300 - Random/Multiple Cylinder Misfire Detected

Basically this means that the the car's computer has detected that not all of the engine's cylinders are firing properly.

A P0300 diagnostic code indicates a random or multiple misfire. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A P0302 code, for example, would tell you cylinder number two is misfiring. Unfortunately, a P0300 doesn't tell you specifically which cylinder(s) is/are mis-firing, nor why.

Symptoms may include:
* the engine may be harder to start
* the engine may stumble / stumble, and/or hesitate
* other symptoms may also be present

Causes: A code P0300 may mean that one or more of the following has happened:
* Faulty spark plugs or wires
* Faulty coil (pack)
* Faulty oxygen sensor(s)
* Faulty fuel injector(s)
* Burned exhaust valve
* Faulty catalytic converter(s)
* Stuck/blocked EGR valve / passages
* Faulty camshaft position sensor
* 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.

Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.

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Had the same problem on my brothers Rav4. We changed the Plug wires and the problem is corrected. He had changed the plugs a couple of months ago. We had the code read at Advance Auto, it came up P0300 Random misfire. His old wires looked fine also.

P0300 Diagnostic Code - Random Misfire
Technical description:--
Random/Multiple Cylinder Misfire Detected:---
Exactly what does this code means:--
Basically this means that the the car's computer has detected that not all of the engine's cylinders are firing properly.
A P0300 diagnostic code indicates a random or multiple misfire. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A P0302 code, for example, would tell you cylinder number two is misfiring. Unfortunately, a P0300 doesn't tell you specifically which cylinder(s) is/are mis-firing, nor why.
Symptoms:--
the engine may be harder to start.the engine may stumble / stumble, and/or hesitate.
other symptoms may also be present…There may be rough idle, sputters and stalls and jerks.
Causes:--
A code P0300 may mean that one or more of the following has happened:
Faulty spark plugs or wires, Faulty coil (pack), Faulty oxygen sensor(s)
Faulty fuel injector(s),Burned exhaust valve, Faulty catalytic converter(s)
Stuck/blocked EGR valve / passages, Faulty camshaft position sensor, Defective computer.
Possible solutions for this error problem:--
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 vehicle, 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.
Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or un-metered air getting past the airflow sensor, or an EGR valve that is stuck open.
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IS IT POSSIBLE YOU GOT A WIRE CROSSED? or a plug is cracked and or gap closed up? i would check these. you have the 5.3? what kind of plugs are you running?

Hi,

A quick Internet search on those codes pulled up the following info.
http://www.obd-codes.com/p0440

• Remove and reinstall the gas cap, clear the code, and drive for a day and see if the codes come back.
• Inspect the EVAP system for cuts/holes in tubes/hoses
• Inspect for damaged or disconnected hoses around the Evap purge solenoid
• Check and/or replace the sensor
• Check and/or replace the purge valve
• Have a professional use a smoke machine to detect leaks

http://www.obd-codes.com/p0300

• Faulty spark plugs or wires
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector(s)
• Burned exhaust valve
• Faulty catalytic converter(s)
• Stuck/blocked EGR valve / passages
• Faulty camshaft position sensor
• Defective computer

The P0300 is down to a cylinder misfire, usually it will have a number like 0302 where the 2 would mean the misfire is in number 2 cylinder. When were the plugs and wires last changed? what milage is on the vehicle?
P0720 is the output shaft speed sensor seems to be more of a common problem on the older hyundai's, is the gear change smooth or erratic? has it ever locked itself into gear? if you clear these codes how quickly do they come back?