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Cylinder #5 Misfire


oddboxeldo

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OK, here's the deal, replaced plugs, wires, all coil packs had a local shop do the injector cleaner number, which it did run good for a day or two, then #5 started missing again, so I swapped # 1 and #5 injectors but still #5 is missing. Could it be the ignition control module? At 400.00$ I hope not to guess.

I am sure it is #5 as I am using a snap- on scanner (MT 2500), anybody any advice.

Going Nuts,

Chris

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How do you know it is #5 that is missing? If you are sure it is #5 then I would go back and double check that plug, wire & coil by swapping on at a time and see it the problem follows the swapped part.

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I have had this problem twice after replacing plug wires and plugs. Mine would usually start after 100 to 150 miles. You may have a carbon tracked plug (or two)which will cause the northstar to miss terribly. What you need to do is pull each plug and look to see if it is carbon tracked - it will look like black lightning bolts or just a fine black line on the white part of the plug if any of this is present your plug is bad. Sounds strange but I have had it happen twice with new plugs and have had one plug wire go bad that did the same thing and then carbon fouled the plug again. Check the plugs if it does it again you will need to replace the wire that is bad and the plug again. Also I have had a bad wire set from the dealer as well so if its not the plugs double check the wires. According to the dealer here in cincy this is a common problem on Northstars cost me 160.00 for one plug to learn the hard way. Hope this helps.

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Was #5 missing before the tune up, and that is the reason why you did the tune up? If so I would do a compression test of the #5 cylinder maybe you have a valve hanging up.

Odd problem considering all the work you have done. Lift the hood in pitch dark and listen and look for any high voltage arching. With all of the work that you did I find it hard to believe that any of those components are bad, but its possible, maybe a coil pack failed but I think each coil pack controls two plugs (but I may be mistaken), have you checked for spark at that plug? If you have an OHM meter I would check that ignition wire also, maybe there is a problem with it, sometimes the carbon core burns out especially if it was manufactured poorly and the core was not making a good connection. I am not a big fan of the injector service unless its necessary, what exactly did they do? Let us know how this turns out, Mike

Early on sailors navigated by the stars at night and the North star became the symbol for finding ones way home. Once you know where the Northstar is you can point your ship in the right direction to get home. So the star became a symbol for finding ones way home or more symbolically even finding ones path in life.

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The misfire is the reason for me to buy the parts I listed and the shop I brought it to did do a compression test and #5 has 195 psi that's what led me to the ingnition control module, wondering if it's the last piece of the puzzel or not? Plugs are new and after a couple weeks still look good.

The scantool is what is listing #5 as the culprit, not sure what are good numbers and voltages are good or bad in the other modes.

Thanks for the posts thus far,

Chris

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The misfire is the reason for me to buy the parts I listed and the shop I brought it to did do a compression test and #5 has 195 psi that's what led me to the ingnition control module, wondering if it's the last piece of the puzzel or not? Plugs are new and after a couple weeks still look good.

The scantool is what is listing #5 as the culprit, not sure what are good numbers and voltages are good or bad in the other modes.

Thanks for the posts thus far,

Chris

I dont know if the ignition module can cause a mis in a specific cylinder, I think it would be random or a no start condition. Can someone verify this I am not fully comfortable with the NS ignition system operation yet. Mike

Early on sailors navigated by the stars at night and the North star became the symbol for finding ones way home. Once you know where the Northstar is you can point your ship in the right direction to get home. So the star became a symbol for finding ones way home or more symbolically even finding ones path in life.

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It has a coil pack (well the pre 2000 ones do I believe) and each coil does 2 cylinders and fires with different polarity or something so the spark is higher in whichever cylinder it wants although it reverse sparks in the other cylinder (this is why you have to use DUAL platnium or iridium/platnium plugs becuase it eats them up).. What you could do is just pull off the spark plug wire to #5 and see if the scan tool says it has MORE missfires and then put it back on and see how many (it should tell you how many it senses per interval)

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Make sure you carefully inspect the white ceramic part of the plugs for carbon tracking it only takes a small amount. I spent alot of money doing what you are doing now and it was a carbon tracked plug. The dealer mechanic found this to be my problem after all the same tests you have run. Sounds too simple but double check.

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