1999 Pontiac Grand Am 1999 grand am se misfiring

1999 PONTIAC GRAND AM
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FLH700
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Shakes or Wobbles problem
1999 Pontiac Grand Am 4 cyl Front Wheel Drive Automatic
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i have a 1999 pontiac grand am whose check engine soon light is on aand flashing. rpm wont move past 1 and speedometer will not go past 30 although it seems like its going 60. also bucks and shakes while driving. diagnostic code stated multiple misfires......was wondering if I change spark plugs would problem be solved?

Thanks
Aug 10, 2008 at 8:33 AM
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MERLIN2021
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First thing you need to do is have the codes read, Autozone does it free, Post the results with the code number(s). Even if the service engine light is not on, there should be freeze frame data stored.
If it won't make it to Autozone, buy a cheap scanner, they can be had for 30-40 dollars, a good investment, since they cover all cars sold in the USA from 96 on...
If the light is blinking, it means possible damage to the converter...service it right away!
In your case the flashing may already indicate the converter is damaged and needs replacement. This may be causing too much backpressure! Loss of power is a sure sign.
Aug 10, 2008 at 8:36 AM
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FLH700
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i did do a diagnostic tesst. The code was 300 which is translated to multiple misfires. spark plugs are worn and i am goiong to relace them, do you think this may be a solution?

Thanks
Aug 10, 2008 at 8:57 AM
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MERLIN2021
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I always go with the basics first, so yes bad plugs will cause random misfires!
Aug 10, 2008 at 9:30 AM
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