85 Bronco 5.8L-W Stalling problem

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May 6, 2014 | 04:13 PM

broncoalex85

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85 Bronco 5.8L-W Stalling problem

So.. When I saw this Bronco I fell in love with it. I knew I had to have it. It didn't run when I bought it from my uncle but I started looking over it and determined I needed a new carburetor. I bought a new holley four barrel for it and installed it myself. And it took a while but I got it primed and running. It will go into gear and move foward a bit but it dies instantly. Any ideas on what could cause this?? I've checked over the vacuum and that seemed fine and checked sensors on the tranny. Any advice would be greatly appreciated. I want to get this beauty on the road again!! I'm a new member here so I'm still getting use to the forum. :P I'll get pics up soon.

May 6, 2014 | 04:42 PM

gatorfor88

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From: Panama City

When you say it took awhile to prime it and it stalls whenever you move it it sounds like m aybe a fuel pressure problem. I would check fuel pump

May 6, 2014 | 06:16 PM

broncoalex85

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It's got a brand new mechanical fuel pump. I replaced that myself also. Hmm.. Its strange!

May 6, 2014 | 08:22 PM

broncoalex85

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And also It doesn't give me time to press the throttle. It cuts off as soon as I put it in any gear. The truck moves about three inches and stalls.

May 6, 2014 | 09:50 PM

Encho

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From: Caracas, Venezuela

It has fresh fuel? did you replace the fuel filter too?. You'll need to be way less vague for us to understand your situation. How much time since it last run? why was it parked? what have you done to it so far?.

May 6, 2014 | 11:54 PM

Torky2

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What transmission does it have?

How does it idle, smoothly or rough?

If it idles smoothly on low idle after its warmed up a bit, but dies when put in gear, the idle mixture may be set too lean. Does this carb have exposed idle mixture screws? If so, back both out a quarter-turn at a time, keeping track of how much, so you know where you are.

And another cause of too-lean can be a vacuum leak somewhere, or the EGR Valve not closing all of the way, usually due to a piece of carbon. An EGR Valve that is not closing all the way will have more effect on low idle than on high idle.

Sometimes when troubleshooting a problem like this, if vacuum is suspected, isolating the vacuum to only the engine can help - i.e., disconnect and plug intake vac connections at the manifold, so no vac going to power brake booster, etc. etc. just for testing purposes.

May 7, 2014 | 12:07 PM

broncoalex85

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It's got a 4-speed AOD transmission in it. It should be the original! It sat for about 2 years when my uncle decided it was time for a new vehicle. :/ Ashame.. I haven't touched the idle mixture screw so maybe that could be a part of it? I will get a smoke machine and try that also. I may get lucky. Do you know if this has an electric fuel pump in the fuel tank?? I replaced the mechanical pump about two months ago so that is brand new. There is several things you're saying that make sense. I havent checked the EGR so i will check that too. Hopefully all of this together will help me get it going again. If not i will have to put it in a shop. I appreciate all the help so far!