firefighter1

Hey everyone! I just bought a 99 GT this past Saturday and it has a bit of a problem. The problem is when I accelerate it hesitates or feels likes it's misfiring. It's only in 3rd, 4th and 5th gear. First and second gear is alright. I'm just a little confused. I may do a spark plug change. If anyone here has an idea, I'd like to hear it.

P.S.

It's my first Mustang! It's awsome!!!

wes ley n the G T

Yes check your plugs definitely.

secureintentions

Is the check engine light coming on at all?

firefighter1

No, the lights not on. It has 72,000 miles on it. It may be in need of a plug change, I assume.

wes ley n the G T

Yea check the plugs. Also, you dont have plug wires if you didnt know already, you have coil-on packs.

firefighter1

Thanks! Yep, knew that one, lol! I'll check the plugs tomorrow. I hope that's all it is.

wes ley n the G T

Ha just making sure man, you wont believe the kids on here that dont know the difference lol. When you get a kid asking how to change his plug wires on an 01 GT, you kinda chuckle

oxfordgt

Also check for a vacum leak that can cause it to miss also.

firefighter1

Yeah, don't worry, lol! I'm hoping that's all it is. The plugs are a reasonable price. I'd like to get exhaust done too.

sweet99

I had a similar problem. Turned out to be a bad coil. When you change the plugs look for one that may be different in color, perhaps more black/sooty. I used NGK platinums and they work great TR55's I believe. Mark