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After 108,500 miles the second ICM bites the dust. This time it is cylinder #2 misfire. Replaced it and it's good to go.

Just a background, the 1st ICM bit the dust at 55,000 miles and it was a cylinder #3 misfire. It apperas that for SoCal heat, the lifetime of an ICM is about 55K miles - maybe. Let see if this one last until 163K miles. :wink:
 

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Mine lasted 83k in Phoenix. Might have something to do with road quality/vibration as well. Overheating doesn't cause a lead to disconnect. That's what happens to the ICMs. The internals are fine, just the connection to the plug fails.

-Mark
 

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Mine lasted me about 55-60 K too. I guess I'll keep my eyes open for a deal.

The most common cause for semiconductors failing is temperature. The hotter they run, the shorter the life. A ~5 degrees C increase in temperature will decrease the average life of the device by 50%. Make sure you use thermal compound under the ICM, but the thinner the layer the better. Thermal compound is not a very good thermal conductor, but it's much much better than air.

Also, thermal cycling is bad. The repeated heating and cooling of the chip in the ICM causes stress on the chip and the wires that are bonded to it.
My guess is that's why they moved the ICM off of the air filter box. Every time you step on the accelerator, the airflow to the ICM heatsink changes and the ICM heats or cools.

Looks like VW is still battling this though, they moved the chips to the coil packs and now the coil packs die :cry:
 
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