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P0300 Diagnostic Code - Random Misfire
Symptoms.
Engine may stumble or miss
Engine may be hard to start
you may notice no issues
Cause
Failing spark plugs or spark plug wires
Bad coil or coil pack
Failing oxygen sensor(s)
Bad fuel injector or more than one
Stuck exhaust valve
Bad catalytic converter
EGR valve or valve passage clogging
Bad camshaft position sensor
Bad PCM or ECM
The Fix
Best first action is a tune up, new plugs, wires, inspect all hoses and wire connections then reset the code. If it returns you will need to narrow it down to a system, coils and coil packs should be tested, catalytic converters for function ( do you smell rotten eggs?). A misfire that jumps cylinders could indicate a lean condition, do you have any other codes along with the 300? this will help clue you in to the source, check valve function to make sure they are opening and closing fully.
This is probably pone of the most difficult codes to troubleshoot, so start with the basics and work your way into the more expensive options, in many cases a good old tune up solves the problem, back it up with a fuel system cleaning and see where you stand.
Wiki User
∙ 9y ago
Wiki User
∙ 11y agoP0300-random misfire, P0306-cylinder no. 6 misfire, P0308-cylinder no. 8 misfire detected.
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Will engine light turn on with a bad valve?
Yes. At least one or more of these codes would come up, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 or P0308.
What does P0308 code mean in a 2005 Dodge Durango limited?
That is a cylinder number eight misfire.
98 dodge durango fault codes p0300 p0301 p0302 p0308 p0135 p0171 transmission was just rebuilt engine ran great before mechanic touched it?
last one to touch it is at fault!! take it back & make them fix it.
99 dodge ram with 5.2 motor with engine code p0308?
P0308 is cylinder #8 misfire. See related question below for info about misfires.
What does P0308 trouble code mean?
Trouble code P0308 means: Cylinder #8 misfire detected
What is diagnostic code p0308 for a dodge Dakota?
Cylinder #8 misfire. Something is causing #8 to not fire properly, suggest you start with a tune up.
What is the problem code p0308 on 01 durango?
Cylinder #8 misfire.See related question below.Cylinder #8 misfire.See related question below.
What is code P0308 and P0316 on a 2002 ford F-150?
p0308 is a cylinder 8 misfire , can be several reasons why
2000 sienna 81thousand hestating after changing plugs with check engine light on?
Must have damaged a spark plug or mixed up the firing order during replacement. Check the code(s) and you may find a P0300 thru P0308 which will help determine what cylinder is misfiring.
What is Lincoln LS misfire code P0308?
Misfire in Cylinder No. 8.
What if check engine light is flashing?
Flashing engine light on virually any vehicle almost always points to at least 1 cylinder misfiring. It usually is a P0300 - multiple random cylinder misfire code...but I've seen cases with a P0301 through P0308 (cylinder 1-8 misfire...or through 12 if you're lucky enough to have 12 cylinders lol).
How do you fix a cylinder misfire in a 1996 Chevy V8 5L?
First thing is to find out why it is missing. On a 14 year old engine replace the spark plugs and wires if you have not done so recently. Also see if the fuel injector is working properly on the cylinder with the miss. If this is not the problem then run a compression test to see if there is a blown head gasket, broken ring, or burnt valve on that cylinder. If it has coil over plugs then check that coil.Have your local auto parts store read the code(s) to determine which cylinder has the misfire. The code(s) should include one or more of the following, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308. The last number on each code determines the cylinder at fault. P0300 is for a random misfire. Once you have determined which cylinder is at fault, remove the spark plug and notice if the business end of the spark plug is wet or dry. If it is wet, you probably have a spark issue be it a bad spark plug, spark plug wire or cap and rotor. If the spark plug is clean and dry, you may have a fuel injector problem. If all that checks okay, do a compression test and compare that cylinder reading with the other cylinders. Ideally, you would like to see all the cylinders compression readings be within 10-15% of each other. If that bad cylinder has low compression you may have a valve or piston rings issue.
