stomping gas helps
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Joined: Sep 2000
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stomping gas helps
Got a stumper. 1984 F150 IL6 auto trans. If I start the truck & drive it seems to sometimes miss a cylinder. Acts like it wants to sputter & stall. Gas milage is real poor & it will seem like a low idle.
If I get in & start, then let the motor rev like mad a few seconds, then it runs fine (maybe a puff of black smoke while revving). Gas milage is fine, idle will be ok.
Any thoughts?
Thanks
Walter Danek
:-X11
If I get in & start, then let the motor rev like mad a few seconds, then it runs fine (maybe a puff of black smoke while revving). Gas milage is fine, idle will be ok.
Any thoughts?
Thanks
Walter Danek
:-X11
Postmaster
Joined: Jul 2001
Posts: 4,038
Likes: 3
From: South Kitsap County, WA
stomping gas helps
>If I start the truck & drive it seems to sometimes miss a cylinder. >Acts like it wants to sputter & stall. Gas milage is real poor &
>it will seem like a low idle.
>If I get in & start, then let the motor rev like mad a few
>seconds, then it runs fine (maybe a puff of black smoke
>while revving). Gas milage is fine, idle will be ok.
Sounds like a carb problem, especially the puff of smoke. When you start it up, I assume you give the accelerator a pump to set the choke. A combination of a sticking choke and too much gas maybe the problem. The revving is unsticking the choke or setting correctly. Maybe a can of carb cleaner is in order and a checking of the choke linkages.
Usually a choke that is stuck shut will result in a high idle condition once the engine warms up. Have you let the truck sit after you've started it until it warms up? Just to see if it smooths out or idles high.
Another thought is the choke isn't shutting, but your high idle cam is engaging. This would cause a sputter as the choke butterfly is floating around and not responding right until you rev it.
Hope that starts you out right.
-Kerry
>it will seem like a low idle.
>If I get in & start, then let the motor rev like mad a few
>seconds, then it runs fine (maybe a puff of black smoke
>while revving). Gas milage is fine, idle will be ok.
Sounds like a carb problem, especially the puff of smoke. When you start it up, I assume you give the accelerator a pump to set the choke. A combination of a sticking choke and too much gas maybe the problem. The revving is unsticking the choke or setting correctly. Maybe a can of carb cleaner is in order and a checking of the choke linkages.
Usually a choke that is stuck shut will result in a high idle condition once the engine warms up. Have you let the truck sit after you've started it until it warms up? Just to see if it smooths out or idles high.
Another thought is the choke isn't shutting, but your high idle cam is engaging. This would cause a sputter as the choke butterfly is floating around and not responding right until you rev it.
Hope that starts you out right.
-Kerry
Postmaster
Joined: Jul 2001
Posts: 4,038
Likes: 3
From: South Kitsap County, WA
stomping gas helps
>Usually a choke that is stuck shut will result in a high
>idle condition once the engine warms up.>
That doesn't sound quite right. What I meant to say is a choke that is set in the semi-closed position and the fast idle cam is engaged will cause the engine to rev excessively high when it's warmed up.
OK, back to what you were doing.
-Kerry
>idle condition once the engine warms up.>
That doesn't sound quite right. What I meant to say is a choke that is set in the semi-closed position and the fast idle cam is engaged will cause the engine to rev excessively high when it's warmed up.
OK, back to what you were doing.
-Kerry
More Turbo
Joined: May 2000
Posts: 655
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stomping gas helps
Check all you vacuum lines for leaks too. A vacuum leak will raise hell with the idle circuit. A good bet is (if there is enough hose) to trim off the vacuum hoses about 1/2" at each end and re-attach. This will ensure a tight fit.
