I have 177k miles on my CT and it recently started doing this almost on every start. I found out that if I put in Neutral it eliminated the vibration and shaking. I also replaced the spark plugs and it hasn’t done it since. I am planning to clean out my EGR cooler and intake manifold. Apparently this is normal based on all the Prius and CT200 threads I’ve read.Don't believe that at all.
Very common occurrence on CT,Prius and Auris (UK).
None have been due to head gasket failure. This engine doesn't suffer from head gasket problems and I've never read of any either.
Does the engine suffer from coolant loss?
Are you having to keep topping it up?
Is there any oil in the water and water in the oil?
Which cylinders are misfiring ?
Mine had this problem last winter. I cleaned out the EGR valve and pipe and used a fuel injector cleaner. The car hasn't suffered with it since. It was also a really scary bad shuddering too.
Sorry for the questions but I would investigate it more as you don't want to be paying for things that aren't required.
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