GT fireman

Just recently purchased a used '05 GT 4.6 w/manual shift, having occasional missfire issues, took it to a local ford dealer for a computer check. Along with a couple of other issues that were found as to why this GT sat on a car lot for so long I was told that the CATs had been blown out. Question is to some of you that have been around, " are catalytic converters even necessary or should I replace them ". Running MSD coil packes and violator exhaust system.

03gt04mach1

If you have Emissons Inspections in your area, then yes. If not, you just have to fool the Computer.

Seabee1993

Also keep in mind the warranty for cats is federally regulated for 80,000 miles. So you have low miles ford has to fix that mess.

cliffyk

Not if someone deliberately beat out the cores.

One other comment though, in most states it is illegal for a licensed dealer (new or used) to sell a vehicle that has defective emission control components. Unless it was sold "as-is" the dealer has to either fix it or take it back...