I have a 1991 Audi 100. The problem is, when I first start driving everything is fine until the engine warms up. At that point the engine starts to struggle. When I press on the gas it seems like its not getting any gas and it feels like the car wants to shut off or it just dies. But when it cools off, it'll run fine till it warms up again. I changed the fuel filter and fuel pump already. Much appreciated if anyone can help.

 

Check the Relay and make sure it is not heating up....is it covered? has there been water getting into the fuse panel area??? take a look and see..Mine is up front under the hood right under the windshield..on the drivers side...make sure it is covered...