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annoying missfire

Ok, the car is a 99 Grand Prix with a 3.1 engine.. The car has developed a miss and it's driving me crazy.. I bought a code reader from Harbor freight and it tells me code 0305.. Which according to the book that comes with the code reader, is a "misfire on cylinder #5".. I pulled the sparkplug and it was not fouled, but it was damp with fuel.. From not firing.. So, I changed the sparkplug and installed a new wire as well.. I get spark from the terminal on the coil but cannot check the spark from the sparkplug side of the wire due to the way they are routed (firewall side of engine).. I still have a miss.. What am I "missing" something wrong with the injector? George

Reply to
George King
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George- I had the same thing happen on my 94 grand prix. Try this with Cylinder

  1. Take a 3/8 extension, and lightly tap on the #5 injector, and see if it helps at all. It did mine, and it turns out the car had a bad wire in the injector harness. I have yet to replace the harness, and I probably won't until my 'fix' I just described above doesn't work for me anymore.
Reply to
clevere

As a temporary fix you might try some injector cleaner such as Chevron with Techron. Also check out

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and see if any of the toptier gasolines listed are available in your area. My 98 Montana was missing firing on #5. I swapped the injector to another cylinder. The miss fire stop for about a day and returned on another cyl. not associated with the #5 injector. To shorten the story I ended up buying a set of reconditioned injectors thru an outfit at
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Problem hasn't returned in over 10000 miles.

Reply to
DonW

Well after trying everything else, I decided to try this recomendation.. It worked! Thanks! George

Reply to
George King

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