87 13b won't idle and lack of power

[jimmys79rx]

i think we have a ground issue somewere the radio has bad noise in it when the car is running also. i replaced the grounds to the ecu, did nothing, when the car first came to the shop the tach wasnt working at all, i replaced the trailing coil, it still didnt fix it so i swapped it back out, tapped on the dash the tach started working intermitently, is the grounds behind the cluster or in the dash that would cause the drivability issues this thing is having too. any help would be great

[NoDOHC]

Have you tried the usual?

Check compression
Check fuel pressure, stopped and running
Verify ignition on all four plugs (using inductive timing light)
Check timing
Run dedicated ground wire to the ECU grounds on the engine

If you could describe what the engine does under throttle blips, WOT, Idle, deceleration in and out of gear, etc. it my give us a better idea of the problem.