Acceleration shudder over 65mph

[hawkfandan]

Have 11 SHO. Have replaced plugs, wires, boots, most coils and all the fuel injectors.

I recently had a cylinder 3 misfire and changed the coil and plug (the plusg a 2nd time) and yesterday my cel went off is when doing.a hard acceleration over 65 (up a hill.or passing).

Mainly had done all city driving since the aforementioned plug replacement.

Car shirts good, drives good otherwise no issues with acceleration.

I've spent thousands trying to get it right. I need some ideas what could be wrong!?!

 

[luigisho]

swap the #3 coil with another and see if it follows. It's always possible to get a replacement that isn't as good as you would think. After that if it keeps being same cylinder specific then there is either a fuel, vacuum issue, or something with the circuit firing the coil or a cylinder internal specific issue. The easy stuff has been done it looks like.
To get better responses you need to post this in the Gen 4 section that is specific to the newer turbo models of SHO. This section is the early non turbo cars

 

[hawkfandan]

I'm sorry I thought I posted it in right section

 

[Irish Pride]

Moved to proper section.