I was driving last night no problems. Just replaced battery, alternator, plugs, coils among lots others. Car has been great. Parked for the night went out this morning n nothing. All lights come on, battery n starter are fine obviously. What's going on. Y am I getting nothing or what goes bad or something. Wires n terminals all good.??? 98 A4 Quattro 1.8T

 

No cranking is generally the battery. Even though you said you replaced it, it may have been bad (somehow) or it worked once then a bad new alternator didn't charge it so it's already dead.
First thing I would do is get a mutlimeter and test the battery.

After that it could be an ignition switch or some electrical ground somewhere.

 

I tried three different batteries from other cars I have ik those are good. N multimeter says all is charging and good. Even volts In dash go up to 15volts like normal. It's like ignition is getting no power or power to starter or somthing. Idk what the problem is but car was fine last night n just won't start now

 

I just picked up a 97 A4 Quattro for FREE because the previous owner could not get it started. Try turning the key on and holding it in the start position and push up on or move the shifter while it's in park or try to start it in neutral. That worked for me and all I had to do was just tighten up the cable to the shifter. Just give it a try.

 

Mine is manual awd turbo. Still haven't figured it out. Replaced battery brand new starter brand new alternator again brand new. Tested wires to clutch switch and ignition all working. Still won't start