Anyone know if there is a difference in the coil packs or wiring between a 96 A4 2.8L quattro engine, and a same year A6 non Quattro 2.8L engine? The A4 has a part number ending in 5101C, and the A6 has a part number ending in 5101A. Is it just the aluminum frame that the coils are mounted on? Can i pull the coils off the A6 frame and put them on an A4 frame and use them in my car?

 

I don't see why they wouldn't be interchangeable. I don't know all that much about coilpacks, but I DO know there were several revisions that Audi released as recalls because the originals were prone to misfire. The revisions were given letter designations which were appended to the part number. would be worth a shot to try it at least.

 

I can't imagine there is a difference in the coils or wiring to them either, but the parts lists for the various 2.8L 12V engines over the years still carry the 5101A part number for some, and the 5101C for others. Some of the later cars than mine still have the A number listed. If it was purely a part number revision you would think the A's would dissapear and all the engines would carry the C revision number but they don't. I've got a misfire on cylinder 5 but i've got some other stuff to check before I jump in and buy a new coil set. The car seems to run fine, with just an occasional bump in the idle (like once every few seconds) the plug looks like its might be running lean but i haven't compared it to the other plugs in the car and I haven't checked the injector yet, so after I do that I'll worry about the coil being good or bad. Tried to swap a wire to see if the misfire follows but theres no pair that when pulled will reach cylinder 5 and whatever other cylinder I get the wire from, and i don't have any spare wires just laying around.