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Discussion Starter #1
I've been plagued with misfire codes ever since i bought the car. It drives well, but the lumpish idle and lean spikes/hesitation when crusing are kind of annoying.

I got the car retuned recently with new spark plugs a few weeks ago, but the issue is still here. (Maybe they were fouled during the tune.. ?)

I get random cylinder misfire codes as well as #2 and #6 misfire codes.

I'm going to replace the plugs again next oil change, but other than that what else should I look at?
 

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Cherisher
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Have you replaced the spark wires? I would OHM out the coils if so. The specs are floating around here somewhere... I posted them a few times with pics from the manual :)

What are you gapping the plugs to?
 

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Discussion Starter #5
Have you replaced the spark wires? I would OHM out the coils if so. The specs are floating around here somewhere... I posted them a few times with pics from the manual :)

What are you gapping the plugs to?
Stock plug wires. I'll prob order a set of NGK plug wires the same time I do my plugs since they are cheap.

I'll look around and get familiar with ohm'n out the coilpacks too.

I am using NGK6282 Copper Plugs gapped to .30.
 

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2 years ago I had misfire issues with only #1 & #6 . I changed to NGK plug wire and still misfired. It turns out I had tiny vacuum leak causing the misfires.
 

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Discussion Starter #7
I sprayed half a can of break cleaner on all the hoses i could see and it didnt hear a change in idle. What method did you use to identify the leak?
 

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Discussion Starter #8
Just an update. I got my car back a few months ago from a shop that replaced my turbo. They changed the spark plugs after a compression test so I figured they were all good.... They were gapped anywhere from .22 to .30. Ridiculous.

I got some new NGK wires (old ones had some wear on the rubber head), 6 new spark plug and gapped by my self with a feeler gauge @ .28, tested the resistance of all 3 coil packs (came out at .7ohms across the board), swaped the position of all 3 just to be sure.

Runs smooooooth now. Finally.

I guess if you want it done right you gota do it yourself!
 

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Discussion Starter #9 (Edited)
ITS BACKKK! :(

My idle slowly got more and more lumpy. Two days ago I replaced my MAF sensor with a new OEM one. Today I got a cel form misfires from cyl 2 and 6 again.

What do i look at next? Injectors? Increasing/decreasing my gap? Fuel pump? I am annoyed to say the least.

EDIT: I just remembered i dropped my idle timing last night from 17.5 to 13.5. What have you NA-T guys have your idle timing set at?
 
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