1998 4runner v6. Last year I replaced #1 fuel injector, new plugs & wires. Now I am getting check engine light. Autozone read codes as follows: P0300, P0301, P0303, and P0304. I cleaned the MAF sensor and made sure the wire was still there. Reconnected neg battery cable. Still getting check engine light. Any thoughts? Coil pack? Another injector problem? Thanks.

SOURCE: 99 4runner misfire

make cranshaft gear has not spun under timing cover ive seen it happen before

SOURCE: start and diesss

p0456: evap system. sensor failure
p0172: evap system. intake blocked
p0778: exaust valve control. solenoid/ecu faukt
p0300: cylinders misfire. check ht/ignition leads
p0301,303,304,305,306: same ht leads

hope this helps..

SOURCE: Misfire with error codes P0300,P0302,P01303, P0102, P0748

have you checked the wires for holes.

Patrick Allen

• 171 Answers
• Posted on Jan 19, 2010

SOURCE: Took my car to Autozone and came up with P0300,

The codes are misfire codes. Try changing the spark plugs and spark plug wire first, that's usually what it is. You may need to unplug the battery afterwards to reset the light, just unplug the positive cable for 5-10 minutes to do this, then plug it back on. If it comes back on you may need a new coil pack, but that's usually rare that happens.

Iron

• 3018 Answers
• Posted on Aug 19, 2011

SOURCE: error codes p0300 p0304 p0604

• Hi,
• Here is a list of the code definitions you have listed.

• P0300-random/multiple misfire
• P0303- Cylinder 3 misfire detected
• P0304- Cylinder 4 misfire detected
• P0604 - Internal control module random access memory error (RAM error)

• You done well to replace the things you have.
• Since you have replaced the plugs and plug wires and you are sure the are good the we move on to what else could be going on.
• A faulty coil pack can be at fault as well. So if you had these codes before and after your repairs then the coil pack is the next thing to look at.

1. Coil packs really just have 4 - 6 bolts to remove them and a new one sets in it's place.
2. Make sure to mark your wires so you don't loose the firing order.

• A bad catalytic converter can cause the P030X codes as well.

• The unfortunate thing about the P0604 code that is associated with the other codes is something KIA was know to have problems with back in the 2000 year time is the ECM that often needed replace.
• Make sure to check the wires and connectors for the ECM as well but many had to replace the ECM on this vehicle.
• This could be either thing I listed.

• If you have any comments please feel free to leave them here.
• Hope this helps and thank you for using FixYa.