I just had the intake manifold gasket replaced in my 4.6 Triton, should I replace the spark plugs? As I'm sure the mechanic didn't put new ones in.

 

How many miles, when were they changed last, if you know? Your question doesn't really give anyone any idea of any trouble you have other than a new intake gasket? Is it running poorly still? What year make model? Details are important, they help other members figure out what you have going on

 

Yes its a 98 F-150 XLT Lariat with the 4.6 Triton motor in it and has 198,00 miles. The plugs are only a month old. I replaced coil packs, plugs and wires and had the leak in the intake manifold gasket fixed. It's running good you can't hear the misfire like before it was fixed but still just feel sluggish.

 

If it feels sluggish your cats may be clogged. Take it to a muffler shop and get them tested for excess backpressure.

Did you use all Motorcraft parts?

 

Did you have any codes before the intake was fixed, or after?