302 problem
Thread Starter
|
New User
Joined: Jan 2002
Posts: 22
Likes: 0
From: battle moutain united sta
302 problem
:-X23 ok heres my problem. My 1991 ford f-150 302 (5.0) is surging in and out within the first 15 to 20 minutes of it running. i can have it in second gear and gas it and the engine will rev up a little but it wont go berly.after 15 or 20 minutes it will run like a bad out of hell.need help. thanks.
Moderator
Joined: Jan 2001
Posts: 57,025
Likes: 2,758
From: Virginia
302 problem
We can try the simple stuff first. My first thought would be some bolts on the intake system are loose somewhere. When it is cold, it's sucking air somewhere. Then as the truck warms up, the metal expands making the air leak go away. I would go around and tighten all the intake manifold, air plenum, and throttle body bolts and then see what happens.
Postmaster
Joined: Nov 2001
Posts: 3,351
Likes: 1
From: Escondido, CA
302 problem
Put a vacum gauge on the engine on and start it after tightening your intake bolts. See what it reads. Meaning look to see if you have a noticable increase in engine vacum going from cold to hot. Or if the gauge is bouncing around. Another thing to do is look over your EGR valve. No, on second thought hold off on that. If it was the EGR you would have low idle or stalling.
Senior User
Joined: Nov 2001
Posts: 345
Likes: 0
From: oh
302 problem
Many times you can find a vac leak using vac gauge and "UNLIT" propane torch. The propane will get sucked in and eng speed's up and smooth out. You have enough age ,miles, heat it's time for leaks to start.
