94 Ultra's gotta shake at 50 to 60 mph

[Cntrysthbst]

I let off the pedal at 50 to 60 and no shake, push pedal and shake, gotta miss a idle to and thoughout drive. Any clues? No codes.

[Cntrysthbst]

I still haven't replaced the converter, can this be causing this problem?

[kok328]

Sounds like a breakdown in the ignition system (plugs, wires, coils).

[Cntrysthbst]

Just had a tuneup. Coils would put a code off right? Will recheck all wires and plugs.

Plus , if I'm going 50 to 60 and floor it no shake, just lack of power. Seems like it doesn't really shake bad till it goes into overdrive. Shift it to 3rd at 55mph and doesn't shake bad.

[HotZ28]

Coils, wires and plugs are considered parts of the “secondary ignition system” and will not throw a code if bad! The cat can cause a loss of power & sputtering under load due to the restriction, however your symptoms sound more like a breakdown somewhere in the “secondary ignition system”.
It could also be a combination of both!!

[Cntrysthbst]

After I get back from working the intersection down the street here with my "Will work for Buick" sign, I'll be off to the parts store.

[Alibi]

Coils. If I were you I would replace the coils because your symptoms described match mine exacly when mine went bad. Visually inspect them and if there is green-grey goo coming out of the coils or the ICM, then you have to replace both.

Replacing the plugs and wires wouldn't hurt either if they are starting to get old. A bad coil can foul the plugs too.

[Cntrysthbst]

Ok, replaced the plugs and wires, seems a bit better but the problem is still there. Going to get the cat replaced. Then if the problems still there, will replace the coils. Thanks