my chiuaua is slobbering alot ... he whole neck and face is ...

I'd look in his mouth for any signs of dental disease such as lots of tartar on the teeth, a broken tooth, bleeding gums etc as dental disease can cause digestive upset as the bacteria in the mouth get swallowed.
The dog flu is not an intestinal upset its an upper respiratory disease.
If you think all his teeth are nice and clean the drooling may be from nausea which can also go a long with diarrhea. You can have the vet check a fresh stool sample (without the dog going in just bring a stool sample and its fairly inexpensive to do it) to see if the problem is intestinal parasites.
To help with diarrhea try giving him some plain canned pumpkin or some cooked sweet potato as the fiber will help with the loose stool.
If his teeth look off or the stool sample is clear you should see the vet with your pet.
Hope this helps you!

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