Can't figure it out

[orange1983ranger]

When I start the truck I have to- turn the ignition once, it dies right away if it catches at all. Turn the ignition after pumping the pedal twice, it catches and sounds like crap then if I feather the pedal just right it will stay running or it dies. Turn the ignition a third time after pumping the pedal twice, it tries to stay going while i figure out where to hold the pedal so it won't idle really high or die. All the while I have to hold my foot on the pedal for 3 to 5 minutes so it will stay running. the carb is a motorcraft 2150 and the engine is a 2.8l v6. I thought a fast idle sensor was bad, but everywhere I look there is no fast idle sensor for the engine. Any ideas?

 

[Lil-Pony]

What's the condition of your wiring harness?

 

[dangerranger83]

Sounds like it's starving for fuel, had that issue happen to me when I had my 2.8, just all the sudden went to take off and it wouldn't run for its life, turned out to be my fuel filter.

Could be your fuel filter is clogged or the carb needs a good cleaning.

Sent from my rooted SPH-D710 using Tapatalk 2

 

[RonD]

Is the Choke plate(top of the carb) closed when first starting the engine?
On some carbs you have to push the gas pedal down once to set the Choke plate closed.

The Choke plate causes the engine to suck more fuel from the jets when engine is first started cold, if it is not closing then it would be very hard to start and keep running until warmed up.
It is usually operated by a coil spring in a round housing on the side of the carb, this spring is heated either by electrics or exhaust so uncoils as it gets warmer and the Choke plate opens once engine is at normal operating temp.

And the opposite can happen if the Choke plate is closing too much when weather is warm, it floods engine when first starting.
I remember putting wooden cloths pins on Choke plates so they wouldn't close all the way in the summer, lol.

How does the engine run once warmed up?

 

[wildbill23c]

Sounds exactly like my 84 Bronco 2. The choke on mine is disabled because the electric part of it never worked, keeping the choke closed. I tied the choke plate wide open, and yes its a pain to get started, however I pump the gas pedal about 4-5 times, then start the truck, I keep my foot on the accelerator for a couple minutes then drive away as it will just die if I let off the accelerator. So I just drive it to warm it up so it won't die. It doesn't idle at all when its cold, but after I drive it about a mile its warm enough that it will idle.

 

[RonD]

You can add a manual choke cable, kits run about $8-$15

 

[wildbill23c]

RonD, That's my plan here this summer sometime. I'd rather have the manual choke anyhow, less electrics and electronics the happier I am in the first place LOL.

 

[kimcrwbr1]

Get carb spacer # 60529 felpro surface the base of the carb on a flat metal surface with 200 grit and make a gasket for inbetween the spacer and the carb. Then tighten the carb snug do not overtighten it. Here lately I just use my tablesaw and work the carb slowly in a figure 8 pattern until the base all shines the same. The carb spacer is off of a 302 but works good as an insulator from the manifold and it seals all the big vacuum leaks you have on the base of the carb.

 

[wildbill23c]

So my issue could be a massive vacuum leak from the carb base and the spacer. That sounds extremely logical, may try putting the other spacer back on this weekend and see if there's a change in operation. I can here a hiss when its running at idle, but I can't find where its coming from, is there normally a hissing noise at idle from the jets injecting fuel? I didn't think the fuel pump would create that much pressure to cause a hissing noise. I've sprayed carb cleaner around the back of the carb while at idle and the engine idle speed changes slightly meaning its sucking air from somewhere but I can't pinpoint it, so the spacer thing makes a lot of sense, I change it when I put on the other carburetor, so I'm thinking its not sealed properly leaning towards that being my hissing noise and the problem starting and idling when its cold.