I've got a 1987 F150, 67000 original miles, runs rough, sometimes stalls after sputtering for a few seconds. The engine is the 6 cyl. with EFI. I 'm thinking EGR or PCV valve. Any other ideas?

 

Try cleaning the throttle body out (with the engine running)or the air by-pass valve.
Let us know how you make out.
Jerry D

 

It seems the rough running happens only during accelerating from a dead stop. It sputters and sometimes stalls, but only happens quite intermittently. I took it for a test drive and it ran fine for me.

 

Sometimes changing the plugs and wires makes all the difference in the world.. How old are they?

 

I changed the plugs and wires about 2 months ago.

 

Mike,
I would do a good tuneup.Since you've done the plugs already check the wires,cap,rotor,air filter,and change the fuel filter.
If that doesn't work try cleaning the throttle body.
Jerry D

 

Thanks for the info. Jerry. The plugs, wires, air filter, and fuel filter are new. That leaves the cap and rotor to check out. Others have recommended the throttle body too.

 

Check your Chiltons or Haynes manual and read the part on Engine Self Test. Get a manual if you don't have one. Then check out this site:
http://www.dalidesign.com/hbook/eectest.html
It tells you how to hook up a jumper wire, run the self test, and read error codes through the check engine light on your dash. Very easy to do and will help pinpoint problems when they occur on our computer-controlled fuel injected trucks