1985 gt convertible ruff idle & slow throttle response

Myfirstgt · Oct 23, 2023

I don’t know if these 85 mustang gt have altitude adjustments or not. This car came from Ohio. I was told the car had a full tune up on it before it was delivered here, but it has a ruff idle and when I hit the go pedal, it hesitates for a second. I didn’t know if it just needed some top end cleaner or parts and adjustments?

Potomus Pete · Oct 23, 2023

How long has it been sitting....I don't know much on the carb, but seems easy enough

limp · Oct 23, 2023

i would check the vacuum lines.. The precomputer " smog " on these cars is full of vacuum lines.... With the age of this car I would assume they are in pretty poor shape if they are still original....

Myfirstgt · Oct 23, 2023

Not really sure how long it sat. I doubt it was very long. Owner passed away and car was sold. Obviously the dudes who did the tune up on it and said it was running great had No idea. I will inspect all the vacuum hoses and see what I can find. I’m pretty sure everything on the car is original. I take some pictures.

Mcmahst · Oct 23, 2023

And put a vacuum gauge on it. I suspect you’ll get a low reading. Vacuum lines would be my number one suspect.

General karthief · Oct 23, 2023

There are 'squirter nozzes' pointing towards the center of the front barrels of the carb, those are for the 'accelerator pump' that should shoot some fuel out when the go peddle is pushed. If no fuel shoots out the accelerator pump is bad or needs adjustment, may need the carb freshened up. Ever work on a fuel atomizer (carb) before?
There are other things that could cause the symtoms you are having

Myfirstgt · Oct 23, 2023

I’ve never worked on these type carbs. I’ve done quite a bit of mechanic work on my trucks and cars over the years. I need to find a vacuum hose diagram for this GT.

Mcmahst · Oct 23, 2023

Try this:

http://www.carbdford.com/tech/enginesketch.jpg

Myfirstgt · Oct 23, 2023

Good lord that’s a lot of vaccum lines. Guess I’ll be busy for awhile. Thank you Mcmahst.

85GTStangGuy · Oct 24, 2023

Is this car an automatic or a manual?

Monkeybutt2000 · Oct 24, 2023

85GTStangGuy said:
Is this car an automatic or a manual?

This is KEY information.

Myfirstgt · Oct 24, 2023

General karthief · Oct 24, 2023

That may be CFI?
Central Fuel Injection. Looks like a carb with a couple injectors stuck in the top of the throttle body.

Myfirstgt · Oct 24, 2023

You are correct. That’s what this car has.

AeroCoupe · Oct 24, 2023

Can you post a picture of what you have?

limp · Oct 24, 2023

General karthief said:
That may be CFI?
Central Fuel Injection. Looks like a carb with a couple injectors stuck in the top of the throttle body.

Good point, I always " ASSUME" they are manuals...

Myfirstgt · Oct 24, 2023

AeroCoupe said:
Can you post a picture of what you have?

Absolutely. I’ll take some and post them.

Noobz347 · Oct 24, 2023

Anybody have a complete list of what is necessary to swap one of these to a 4bbl carb?

I don't know a ton about the CFI but I do recall the carbed cars stomped all over them.

qikgts · Oct 24, 2023

Noobz347 said:
Anybody have a complete list of what is necessary to swap one of these to a 4bbl carb?

I don't know a ton about the CFI but I do recall the carbed cars stomped all over them.

I don't think I've ever seen a complete list in one spot. Right off the top of my head... Intake manifold, dizzy and ignition swap as it's got TFI, need to regulate down the fuel pressure or swap to a whole carbed style fuel system, I think there may need to be some minor wiring changes made for the WOT AC cut out switch/emissions deal. I can't think of anything else right now.

Noobz347 · Oct 24, 2023

That's probably a good start. I can't think of any reason, other than a concourse restoration, to keep the CFI.

1985 gt convertible ruff idle & slow throttle response

Myfirstgt

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Potomus Pete

I'm still waiting for the fully nude shots

limp

wrap a little cheese around it and its a done

Myfirstgt

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Mcmahst

General karthief

wonder how much it would cost to ship you a pair

Myfirstgt

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Mcmahst

Myfirstgt

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85GTStangGuy

Monkeybutt2000

Mustang Master

Myfirstgt

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General karthief

wonder how much it would cost to ship you a pair

Myfirstgt

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AeroCoupe

lube between the nut and the face. I know my lubes

limp

wrap a little cheese around it and its a done

Myfirstgt

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Noobz347

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qikgts

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Noobz347

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1985 gt convertible ruff idle & slow throttle response

Member

I'm still waiting for the fully nude shots

wrap a little cheese around it and its a done

Member

wonder how much it would cost to ship you a pair

Member

Member

Mustang Master

Member

wonder how much it would cost to ship you a pair

Member

lube between the nut and the face. I know my lubes

wrap a little cheese around it and its a done

Member

Stangnet Facilities Maint Tech... Er... Janitor

Active Member

Stangnet Facilities Maint Tech... Er... Janitor

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