All the vacuum pods were replaced in July of 2006 and everything worked fine until about 3 years ago when all the airflow defaulted to the side and defrost vents. I did replace the vacuum pump last year with the updated version after reading about the old style grenading, vacuum seems good, door locks a tad sluggish but have always been that way. Finally having a bit of time to work on this car and want to figure this out. Where should I start? How long do the vacuum pods last? I have been reading about the switchover valves as well, are these easy to diagnose?

Thanks in advance

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Brian
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