audiTLC

Drove to a meeting and starting up, it ran really rough & popped a CEL. It smoothed out and drove fine until a block from home where it ran rough again.

Pulled the code - P0303 (cyl 3 misfire) so I am guessing a fouled plug? what else should I look for? could it be a coilpack?

stupid question but which is #3? From the front of engine 1-2-3-4 to the driver. Or 4-3-2-1 nose to tail?

thanks in advance

Hillbilly

Check plugs, and switch coilpacks to see if the misfire follows the coil pack.

audiTLC

Thx,coilpacks&plugs ok. It's the Ignition Module, going to replace tomorrow. I'll update.

audiTLC

update-installed new IgnitionModule-everything's perfect! My wallet is light but car's good.

audiTLC

btw, cylinder #1 at the front (nose) #4 at the tail.
moved coilpacks, checked plugs. the misfire didn't follow the coilpack, plugs look good.

Cleared the codes w/ my OBDII scanner and I put in a new Ignition Module and it fired up perfect.

I'm told the AEB coilpacks are good but the Ign Module goes bad. They are pricey so that sucks. If it goes bad on a long trip, you are at the mercy of the local dealer (if they even have one). Retail is around $350! (luckily I didn't pay that but still $$)

tnthowe

I need to install a new ignition module to my 1985 Audi GT Coupe, but I don't know exactly where it is or how to get at it. Could you please let me know where it is?? Thanks.

smtack

how did you know that it was the ignition module and not the coilpacks. I am having the same problem now. What checks did you run.