If i put a chip on my 2003 a4 1.8tqm would it effect my miles per gallon alot???

 

no, maybe 1-2 decrease... some people actually claim to have more mpg )) That of course when you dont floor it

 

what kind of chip are you thinking of using? most chips will decrease your mpg in order to get the performance upgrades, but some chips actually raise it.

just call different companies (apr, giac) and ask questions. that's your safest route.