I noticed that if I hold constant speed @ 40, the engine will sputter. It goes away when above or below 40. Any suggestions? The other concern I have is I have a torn dust boot. Not sure if it's the rack and pinionor tie rod. It squeeks going straight or turning. Is it a good idea to use replacement dust boot or replace? It was damaged by the lower ball joint breaking under acceleration. thanks.

 

On the 3rd gen (86-89) carb'd models a sputter at @ 40 mph is usually caused by the #7 vac line on the back lower base of the carb being burned/broken. If you have a manual trans, slowly acel in any gear, at about ~1,800 rpm's, does the car seem to stumble?