Thansk for the response. Sounds like a combination of 2 things going on.
A. He is eating the chips and they are not passing through causing him to have an upset stomach OR
B. The wet food is causing him the problems.
My first suggestion would be to try and eliminate him from eating chips as these can get stuck in his stomach and cause severe damage.
Second, restrict his food intake for the next 12 - 24 hours and give him Imodium AD to help clear up the diarrhea.
Third, put him on a bland food diet for the next 2 - 3 days: Boiled hamburger meat and steamed white rice is great way to help get him back on track. You can also add egg as well.
If he is doing better and is not getting worse you can start to slowly add the dry food in w/ this until he is eating normally again.
If he is still being picky about the dry food you can add wet food in w/ it but would limit it to about a spoonful and mix well w/ the dry food. If he is doing well w/ this you can gradually add more wet food over time.
He can have Imodium to help regulate him again. If his condition gets worse, or he develops more symptoms he should see a vet to ensure it is not a GI problem or an infection.
I hope this helps. Warm regards!