rough idle poor gas milage
 

I have a 1990 xlt lariat 6 cycl I just purchased with 80,000 on dash 5spd rough idle and at 65 to 70 mph act like it is missing.Also poor gas milage.

you can check this

Ford Inline Six, 200, 250, 4.9L / 300
https://www.ford-trucks.com/forums/forum52/

or

1987 - 1996 F150 And Larger F-Series Trucks
https://www.ford-trucks.com/forums/forum28/

Welcome to the Maryland Chapter

Have you replaced the plugs and/or the wires with the recommended types? HAve you done anything to try to rectify the problem?

On a different subject, have you considered joining our Chapter? We'd welcome you to the Maryland Chapter. We have a repair day coming up you may be interested in attending to get help with your problem!