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Discussion Starter · #61 · (Edited)
Alright, went back to my friends the other day and checked out the car. read the codes and it gave me p0301 which is a cyl 1 misfire. Cleared the codes, but the misfire + CEL came back right away. Was able to limp it home without issues.

put it on jackstands today. Went through the song and dance of taking shit apart and lifting up the motor and took out the spark plugs / coil packs.

spark plugs all look old but are within spec, none were wet or oily. All four COP’s look very old and original. I think it’s most likely the cause of the issue, should order new ones.

now here’s an interesting part. I also did a compression test. Motor was up to operating temps at 9am but it took me a while to get everything off the car etc so didn’t do the comp test until noon, so the motor was pretty cold at that point.

Cyl 1 - 142psi
Cyl 2 - 132psi
Cyl 3 - 143psi
Cyl 4 - 135psi

This is an original, never opened 283k km (175k mi) so I am very happy to see these numbers.

so I put in the spark plugs (ngk iridium gapped to .030) but I do have a question. Does it matter what coil packs I get? The OEM coils are $500 for the set. But I can get Denso or NGK coils for about half that. Thoughts?

Here’s the cyl 1 COP

Gesture Wood Finger Automotive tire Gas


and here’s the cyl 1 plug but they all looked the same.

Light Automotive tire Automotive parking light Automotive lighting Gas
 

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so I put in the spark plugs (ngk iridium gapped to .030) but I do have a question. Does it matter what coil packs I get? The OEM coils are $500 for the set. But I can get Denso or NGK coils for about half that. Thoughts?
AFAIK, OEM is always the recommended option.
Some people have done fine with aftermarket but they tend to be inconsistent in quality and dependability, even when compared to 'performance' coil packs.

The splitting in your photo is a good indicator of the condition they are in, that tends to happen over time.

If it were me I would just replace with OEM (like I did last winter) but I guess it depends if it's worth it to you.
 

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ALWAYS go OEM. ALWAYS ALWAYS ALWAYS. I have seen multiple times where non oem, even from quality brands like denso/ngk just do not last. i dont know why. it's frustrating for sure. but for some reason non oem is always a hit or miss with how long it'll last. and i'd say at least 90% of the time when replacing any sort of part with non oem that was something smaller (master/slave cylinders/coil packs/sensors/etc), barring spark plugs, they broke/failed fairly quickly.
 
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