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Misfire detected- P0300 p0303 set

Discussion in 'Gen II Prius Technical Discussion' started by Megadeus, Mar 3, 2012.

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  1. Megadeus

    Megadeus New Member

    Feb 23, 2011
    Likes Received:
    Northern IL
    Your Vehicle Year:
    2006 Prius
    I've been running around the forums and my reference manuals trying to nail this one. P0300 p0301 p0303 were set.
    2006 prius btw...

    I drove it around with my scan tool (snap on modis) watching the misfire histograms. I replaced the spark plugs and dried out the spark plug wells of any moisture because I had 'just' washed the car before the misfire happened. Much to my dismay, the misfire was still present and constant.

    I had a dead number 3 cylinder. I swapped coils with another and number 3 was still racking up misfires. So it wasn't a coil issue. I pulled out the #3 plug and put in a new one in case the replacement was a dud.

    No good. Still misfiring.

    I pulled out the number 3 ignition coil and inserted a known good plug. It was lighting off like a Chinese New Year, so it's definitely being commanded to fire.

    I poke n prod trying to find a wet connector, something loose, who knows what. Nothing jumps out at me.

    I performed an injector disable test.

    1,2, and 4 drop rpm's but 3 does nothing.

    It's been a LONG time since I've found a bad injector but I think tonight is a first. Call me wacky, but when cylinders 1,2, and 4 have a resistance of ~12.5 ohms with a bastard number 3 injector reading 14.5 KILO-ohms... makes ya wonder. I haven't found another thread on Priuschat of anyone coming to the same conclusion.

    If someone has, I'd like to read their story.

    At this point in time, I'm sourcing a replacement fuel injector.
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