I'm not sure if the CDI engines have better glowplugs but from the limited number of cold-starts I've done it seems you can add 'cold-starts' as yet another area where the CDI engines out-do the old IDI pre-chamber designs.

I've done about 10 cold soaked starts under 20F and my engine seems to fire on the first compression stroke. It starts the same in 12F weather as it does in 85F weather.

With the advent of synthetic oil requirements in the newer engines I'm not thinking block heaters are all that necessary anymore. I can vividly remember trying to start 220D's with 15w-40 oils in 5F conditions and after a couple of hours of block heater usage the difference in cranking speed was amazing - thick oil is just a huge drag.

Also remember a block heater won't do anything if your fuel is gelled in the tank screen or fuel lines. I've found that even winterized #2 starts to have flow issues below 0F.

Hopefully somebody from Wisconsin or Minnesota with a CDI could provide more helpful data. Two people from Texas and the mid-atlantic region really aren't the people to talk to for true cold-start data.

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