Jrgunn5150
Post Whore
- Joined
- Jun 29, 2007
- Messages
- 12,273
- Reaction score
- 2
I saw a guy chucking a giant rock at his F150 the other day, so I stopped and bought it...
It's an 83 4x4 with a 351w, T19 trans, 208, etc etc.
The guy I bought it from (a mechanic btw lol), said the Holley carb on it was bad when he got it so he replaced it with a Motorcraft.... I was suspicious, but I figured, whatever, he's a window licker, I'll fix it (the choke is a lawn mower throttle, complete with rabbit and turtle lol). After poking around in it, I'm begining to suspect it may have been one of the early feedback Holley's.
I has a ecu type thing under the seat on the driver's side, and a big harness running under the cab up to the engine. I've unhooked every single vacuum line on it except for the PVC and brake booster. It does have egr, it is not hooked to vacuum. It DOES NOT have any type of vacuum line, can, or electrical connector on the side of the distributor so I have no idea how the timing adjusts... It does have a "Duraspark" box on the inner fender, but it doesn't seem to be connected to the distributor in anyway.
The probably I am having, is that the thing will not idle below about 1500 rpm.. It just dies. It idles up around 2200 with the choke closed, and wont go any lower than 1500 with it open. It free revs fine, it has no smoke, and it runs in gear fine. It'll idle down the road at 1100 rpm in fourth gear, push in the clutch and it's over though. It's making the truck really undriveable.
I've nearly eliminated a vacuum leak from my diagnosis, I beleive the truck may have been a feedback carb with computer controlled ignition... Does this make any sense? I'm pretty frustrated with it right now.
It's an 83 4x4 with a 351w, T19 trans, 208, etc etc.
The guy I bought it from (a mechanic btw lol), said the Holley carb on it was bad when he got it so he replaced it with a Motorcraft.... I was suspicious, but I figured, whatever, he's a window licker, I'll fix it (the choke is a lawn mower throttle, complete with rabbit and turtle lol). After poking around in it, I'm begining to suspect it may have been one of the early feedback Holley's.
I has a ecu type thing under the seat on the driver's side, and a big harness running under the cab up to the engine. I've unhooked every single vacuum line on it except for the PVC and brake booster. It does have egr, it is not hooked to vacuum. It DOES NOT have any type of vacuum line, can, or electrical connector on the side of the distributor so I have no idea how the timing adjusts... It does have a "Duraspark" box on the inner fender, but it doesn't seem to be connected to the distributor in anyway.
The probably I am having, is that the thing will not idle below about 1500 rpm.. It just dies. It idles up around 2200 with the choke closed, and wont go any lower than 1500 with it open. It free revs fine, it has no smoke, and it runs in gear fine. It'll idle down the road at 1100 rpm in fourth gear, push in the clutch and it's over though. It's making the truck really undriveable.
I've nearly eliminated a vacuum leak from my diagnosis, I beleive the truck may have been a feedback carb with computer controlled ignition... Does this make any sense? I'm pretty frustrated with it right now.
