I have an 88 legend coupe with a 2.7V6, yesterday i was driving home and it was like 114 out, temp gauge was running hot, it started to miss and hiccup everiy once and a while, by the time I got home it was sputtering. So today, I changed out the plugs and cap/rotor, and it still runs that way, it moves, there is no knocking or chattering but runs rough.... oil is clean as well as coolant. blown injector maybe? car has 193,000 pampered miles on it. i am lost!!! please help... Brian

 

Is it leaking coolant? Are you getting white smoke out the tailpipe? Any steam under the hood? What do you mean by the coolant being clean? Did you check the coolant for exhaust gases?

My first assumption is a blown headgasket, especially if it's the original headgasket. I say that because it's starting to miss, possibly as a symptom of a bad headgasket. It happens when there's a big load on the car. Meaning really hot, A/C on, 25-ish year old car, etc. I blew a headgasket before when it was really hot with the A/C on and loaded down with 3 people and their stuff.

Diagnose for a bad headgasket. The ultimate cause could be a bad waterpump or clogged coolant passage or a bad thermostat but, it's probably the headgasket. If it is the headgasket you also need to have the head and block checked for warpage.