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Can different plugs cause major system warning lights?

Discussion in 'Gen 2 Prius Technical Discussion' started by Muleears, Feb 20, 2007.

  1. Muleears

    Muleears New Member

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    Aftermarket Bosch plugs were installed in my car about 18K miles ago. Yesterday I got the major system warning and the car would not move. Initially it would go on electric, but then when I parked to check it, the car would no longer move. ICE was running at idle but would not rev. After waiting a while and turning it off and on a few times all the warning lights went out. Had it towed to the dealer they tell me the plugs caused a misfire code and it was low on inverter coolant. Does this make sense? This is a classic with 78K miles. Thanks
     
  2. jayman

    jayman Senior Member

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    Most coil-per-cylinder motors are sensitive to what sparkplug you use. I've never been convinced some fancy-schmancy pricey sparkplug is any better than what the OEM intended.

    Low inverter coolant, do you have a leak?
     
  3. galaxee

    galaxee mostly benevolent

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    well, first, they're not meant to take the bosch plugs. but if they caused a problem it would have happened right away.

    was this a P3101 and P3191 set of codes? he suspects something else.

    if you pull the pins out of the glovebox and drop it down, there are 2 ECMs sitting next to each other. the one sitting closest to the center of the car is the one you're interested in.

    look closely, you should be able to make out an end of a string of numbers. the last 2 number should be between 51 and 54. if it is not 54, the dealer should replace that ECM for no charge under emissions warranty until 80k. so do this soon if it applies to you.
     
  4. iaowings

    iaowings New Member

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    I found a study somewhere that stated that you get almost no benefit from different spark plugs. I think they were saying it was like point something percent increase in power and mpg. Basically you don’t get anything but a lighter wallet.