cylinders 5,7,8 misfiring in 2000gt

[ECU5.0]

alright, im posting this for my friend because hes having a problem. its misfiring cylinders 5,7, and 8. it will run fine sometimes and other it will just crap out. its hard to start most of the time and its cut off a few times on the road. the reason im posting this is because he just spent a bunch of money on a new hood and cobra bumper and is not thinking about getting rid of it because of this problem. any insight would be great because i dont know jack about the 4.6 motors. thanks guys

 

[SLOW 97]

Sounds to me like he hosed off his engine and now there is water sitting in the spark plug bores in the heads. Tell him to check all the primary wires going to the coil packs and pull the coil packs and plugs to see if they are fouled. The coil on plug set up is pretty simple and reliable so it shouldn't be hard to find the problem.

 

[ECU5.0]

well we replaced his plugs trying to solve the problem and it worked for like 2 days. im thinking its bad coil packs. he had a friend pull the codes on it. he said it just said that those cylinders were misfiring. and its not 5,7,8 its 6,7,8. how much are new coil packs. hes not very mechanically inclined so he wont ever find the problem, but he knows some pretty smart guys that can. thanks for any suggestions