2003 GTX 4tec losing power

[John S]

Hi All , My 2003 GTX 4tec was running great for about 5 hrs after a tune up and oil change. My friends took it for a ride of about 1/2 hr and came back to tell me that it wouldn't go over 40 mph and was stumbling going on plane. I took it out for a run and that's exactly what it's doing. Had it in the shop recently foe a bad temp sensor. It idles ok but seems like only 2 cylinders ar working at full throttle. Any suggestions?
Thanks, John

 

[KK40384]

Sounds like a plug crapped out on you. Stick a fresh set in and see what it does. There 4tecs are notorious for eating plugs.

 

[John S]

Thank you, I'll try a fresh set

John