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Cylnder 3 and 4 miss fires

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Hello all,

 

Today on the way to work my CEL came on so i stopped by Schucks on the way home. The codes where 303 and 304, which are miss fires in the #3 and #4 cylenders. About a month ago i replaced the plugs and wires. Does any one have any suggestions on what else i should do or look for????

I did have the #4 cyl. miss fire on me 7 or 8 months ago.

1996 OB 2.5 w/165K

 

Thanks

Hello all,

 

Today on the way to work my CEL came on so i stopped by Schucks on the way home. The codes where 303 and 304, which are miss fires in the #3 and #4 cylenders. About a month ago i replaced the plugs and wires. Does any one have any suggestions on what else i should do or look for????

I did have the #4 cyl. miss fire on me 7 or 8 months ago.

1996 OB 2.5 w/165K

 

Thanks

hehehe. What plugs did you put in??? You MUST use the NGK's or Denso iridiums to avoid a 301/302 or 303/304 combo. If you're using NGK's, you've got a wire problem. If you are using NGK plugs, do a resistance check on your plug wires, when you find the culprit, you'll know. But replace em all anyway.:brow:

 

If you don't find any wires that are WAY OFF, check the resistance on your coil pack.

  • Author
hehehe. What plugs did you put in??? You MUST use the NGK's or Denso iridiums to avoid a 301/302 or 303/304 combo. If you're using NGK's, you've got a wire problem. If you are using NGK plugs, do a resistance check on your plug wires, when you find the culprit, you'll know. But replace em all anyway.:brow:

 

i think that i have Bosch plugs in!!!!!!

i think that i have Bosch plugs in!!!!!!

That'll do it. The old Platinum +4 (new plugs). Spend the extra $$$ on the Denso Iridium.

 

Some autozone's stock the item, otherwise it is a special order.

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