TAdan

Hi I have a 1999 T/A, 4l60E, GMPP crate LS6, Spare ECM stock LS6 tune.

A few days ago I was driving in stop and go traffic on a very warm day. The car developed a severe misfire and got very hot, smoke was coming from my catalytic converter. After several minutes the misfire cleared up.

I believe my cats were overheated and ruined due to the misfire.

I scanned the car and came up with the following codes.

P0351: Ignition Coil A Primary/Secondary circuit malfunction
P0353: " C Primary, etc...
P0355: " E Primary, etc...
P0357: " G Primary...

So... any idea what could have caused these four coils to malfunction?

What controls the coils? (ECM or something else?)

The car seems to run O.K. now but it feels like the cats are clogged. (Also how many cats does the car have? I have not been under there in a while.)

Any help or insight would be appreciated! Thanks.

Dan