Runs fine when driving but idles rough

[BWdiver]

My 95 f450 with 177,000 miles runs fine when driving down the road, but idles rough at idle.
going to do the GP maitanance stuff this week for the hard starts and put new VCGaskets and harness on. replaced thermostat as the old one was stuck in open pos.
Had alot of black rubbery feeling stuff in the pre filter 3 months ago so I pulled everything apart and replaced all the rubber hoses and cleaned the little screens. that helped alot...my buddy buzzed all the inj's and cant really say which one may be bad.
I'm hoping the new gaskets and wiring harness will help.

Please help with any suggestions.

[svranger25]

any fix on this my truck is doing the same, rough at idle, fine at speed with no loss of power???