Coil Pack Issue?

[ColinR33]

So I have been noticing the dreaded hesitation/stutter under acceleration load and decided to check my coil packs. Visual inspection of the front 3 came up good , contacts were nice and clean, no visible cracks or arcing, and all tested out at around 0.9 ohms resistance. Then I took the back 3 out and noticed some rust(? red dust?) and pitting on a couple:



and some yellow deposits on the bracket between the coil packs


Could the damage in the first pic be causing the misfire? Resistance still around 0.9 ohms (older style meter, not digital so subject to a bit of error). Any input/advice welcome!

Thanks!
Colin

[cortexx]

The red dust pitting is just rusting of the laminates because the paint has come off , they look fine to me. The resistance is about right , i have a spare set of good coils i took off my car when i installed yellow jalckets .

The coil is just a transformer with a huge secondary winding to step up the voltage many times the input. The only way they fail is open circuit ( will test as massive resistance , many Mega ohms) , or if the insulation breaks down. this might happen only under operation and is very hard to test for with a meter.

The laminated design of the induction bar is made of plates instead of a solid piece because it is more efficient and reduces heat build up caused by collapse and creation of the magnetic field .

[ColinR33]

I did end up cleaning them and put some electrical tape over the rusted spot on the side, did seem to cure the hesitation/stutter for the most part, will monitor and see if it comes back.