Hello, my first of many hopefully "not so stupid" questions. My 86' F150 has been running great all week since I bought it off Craigslist. The gentleman I bought it from, drove it 4-5 times a week, it's got 186K miles on it, and this past Friday, it wouldn't start. So I put a piece of bailing wire (temporary) around the butterfly of the carb so it wouldn't die when I started it. It fired right up, but after driving it from the house to the auto parts store for new plugs, wires, cap and rotor (nothing fancy, MOTORCRAFT Plugs) and having changed them all, it fires up real nice, but idles very, very rough. I let it warm up after a few minutes (temp needle moves to the "O/R" in "NORMAL" on the gauge) shift into reverse and it revs at a lower speed, as soon as I put my foot on the gas pedal it dies.

I start it back up, as long as my foot isn't on the gas pedal with more than a feather amount of pressure it drives well, but as soon as I try and move any faster than 25 mph, she sputters, shudders and acts like a cranky old nag.

Any takers on this? I limped her back home to the barn for a rest. This truck is going to be my daily driver, but it isn't a hot issue fix....yet. There's always my wife's VW Beetle to get me around town. It's like dating an ugly woman, it's fun until your friends see you.

Your help/insight is very much appreciated. - Will

I'd have a look at the timing, check fuel filter and vacuum lines to start with..I'm sure others will chime in as well.

x2 on the fuel filter and vacuum lines....

Double ck. the ignition timing.... and the spark plug wire routing... its something that you did one way or another.... it will be something simple....

Thanks for the input, I will borrow a timing light and double check the plug wires. I did them one by one, plug, then wire. Then I went to the new D-Cap, one at a time so I wouldn't mix them up.

Does it make any sense that once I get it started, it stops shuddering and shaking when I put my foot on the gas pedal slightly? If I press it down and get the rpms to say, maybe 3000, it goes rough again?

Fuel filters and vacuum lines I'll check today as well. Thanks again.

try turning the idle up a little bit,i agree with all the other suggestions but it sounds like a carb issue

also check that your spark isnt going away the ignition modules on this truck had high fail rates

i would say a carb issue as well.had the same symptoms on my 81.rebuilt the carb and problem solved.the problem with mine was the metering rods were sticking open,a real good cleaning during the rebuild solved this problem.

If you run a fuel additive like SeaFoam or STP regularly, it'll help keep carb parts from sticking since some of these lower forms of life gas stations use cheap detergents in their gasoline grrr