a few months ago i had my coils replaced by a mechanic because i was really busy and didnt have to time to diagnose the misfire, now i sitll have a misfire but it isnt as severe, and today i juts noticed that my coils are mismatched 2 are 1 brand and 1 looks used because it actually has the cylinder numbers printed on it and i didnt tihnk that new coils came with that, they also have much different resistance readings, the 'used' one is reading aorund 5k ohms witht he other 2 at 8.6, i called the mechanic about it said it 'shouldnt matter' im like hell yes it matters but unfortunately it was months ago so i'm not in the best of positions to prove he did it

Sounds like you have at least one coil at 8k? That would be a 97 and newer L67 coil. The coils at 5k would be SE/SLE/SSE coils or 92-96 L67.

well i have a series 2 3800 SC, so should they be that 8k or 5k and will it make a difference like i think?

The 97 and newer L67 coils were hotter (greater difference between primary and secondary windings, or in simpler terms, a higher secondary resistance).

One would think that if they were all hotter, or all colder, your idle would be more smooth. Ultimately, all hotter (or MSD, even hotter) is preferred. Smoother idle, and a slight increase in midrange power can be felt.

The advantage for me is that when I gap my colder plugs, I don't have to gap as tight as most would with stock coils, as the hotter coil can jump a larger gap, allowing for quicker (more immediate and thorough) ignition.

ok and could the mismatched coils cause a minor misfire? its so weak one can barely feel it but it occasionally sets off the traction control light, also could a coil with cylinder numbers printed on it be new or is it definitely used?

or culd the computer be mistaking the roughness caused by mismatched coils to be a misfire?

oh btw i would like to have as many answers as possible by saturday, which is when im going over there to confront him about it

If you had a bad coil, like any mechanic he called the parts house and they sent him a replacement. He doesn't look at or concern himself with resistance numbers. That is the called for replacement at his parts house.

On my 97 I believe my stock coils secondaries are around 6.5K

except that they are clearly completely different coils, they don't look at all alike other than the fact that they both fit

it sounds to me like your mechanic replaced coils until the misfire went away for him and left 1 original one still in the car. Check your receipt; the coils are typically $25+ for each one and figure out how many you were charged for, and then confront him if he'* charged you for all 3.

The difference in the new coils is not very significant and won't harm your engine. It'* along the lines of installing higher output Blaster coils.

I would replace the final coil with a new one if I were in your shoes but I'd pull all the coils and the ICM, clean up the connector and the ground plate during the process.

Cheers,
Tim