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1985 gt convertible ruff idle & slow throttle response

  • Thread starter Thread starter Myfirstgt
  • Start date Start date Oct 23, 2023
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qikgts

Active Member
Nov 12, 2001
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FLORIDA
Oct 24, 2023
#21
  • Oct 24, 2023
  • #21
Agree wholeheartedly Noobz347.
 
M

Myfirstgt

Member
Oct 9, 2023
16
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Fla
Oct 24, 2023
#22
  • Oct 24, 2023
  • #22
instead of high jacking my thread, why don’t you start your own?
 
Reactions: Monkeybutt2000

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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Oct 25, 2023
#23
  • Oct 25, 2023
  • #23
Myfirstgt said:
instead of high jacking my thread, why don’t you start your own?
Click to expand...
well basically there is not much you can do to a CFI system that I know of, to get the stuff you got running better you need to first check fuel pressure, see if anyone's fussed with the timing and check what happens to the spark when trying to rev it above 2500 rpms with a spark tester. Pull a plug and see what brand it is and condition of the sparking end, remember these engines don't need any e3 triple gold plated sparklers, just plain old copper autolite -em-ups.
 

85GTStangGuy

5 Year Member
May 19, 2021
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Oct 25, 2023
#24
  • Oct 25, 2023
  • #24
Myfirstgt said:
I don’t know if these 85 mustang gt have altitude adjustments or not.
Click to expand...
I know for a fact the manual 85's (which came with the Holley 4180C) did, so I'd assume the same is true with the automatics, since they both had to meet the emissions standards in effect at that time.

Mcmahst said:
Try this:

http://www.carbdford.com/tech/enginesketch.jpg
Click to expand...
I think that diagram may be for the carb'ed motor, not the CFI motor.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
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Oct 25, 2023
#25
  • Oct 25, 2023
  • #25
Myfirstgt said:
instead of high jacking my thread, why don’t you start your own?
Click to expand...
Nobody hi-jacked your thread. Every post so far has been on-topic.

Now, I know how, don't get me wrong.
 

Mcmahst

5 Year Member
Jan 19, 2021
681
267
83
Laguna Woods CA, fort Mohave AZ
Oct 25, 2023
#26
  • Oct 25, 2023
  • #26
I think you need to start from the beginning. Since we know it’s a ECU driven engine, you need to pull the codes, test the vacuum, compression test, timing, etc. Gather all that and plan your attack. Now, for known problems with this throttle body injector system, the two injectors can get clogged, low fuel pressure fits your symptoms, as well as late timing. But vacuum is still the likely problem. Since the car likely has old vacuum lines, I would just replace them all. My last mid 1980’s Ford CFE problem turned out to be a clogged injector. I can’t remember if I was able to replace the two injectors or I had to buy a rebuilt throttle body. Just my 2 cents.
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,888
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Oct 25, 2023
#27
  • Oct 25, 2023
  • #27
So if you reread what Noobz was saying he was merely asking if anyone knew what it would take to swap to a carb setup to get you another path. I happen to agree with him as my 83 T-Brid was CFI and it was a pile of crap. Switched it to a carb when it got the warmed up 306 and T5 and never looked back.

CFI to Carb swap help! Please god!

Okay. I have a 1985 Mustang GT convertible with an AOD tranny. I can't stand it! I want to go carb so bad but can't find a good, COMPLETE parts list or how to. I've seen tons of little tid bits here and there and peoples GUESSES but I want someone who KNOWS what they're talking about. I know I...
stangnet.com

Lots of threads on the Mustang sites about swapping. The CFI cars have an intank lift pump and then an external high pressure pump on the rear frame rail. From what I remember you can simply remove the high pressure pump and the lift pump will provide enough pressure and volume for a carbureted car. You will need a fuel pressure regulator. The only reason I know this is a guy over on a Thunderbird forum did this with a mild 351W and it ran fine.
 
M

Myfirstgt

Member
Oct 9, 2023
16
6
13
Fla
Oct 28, 2023
#28
  • Oct 28, 2023
  • #28
AeroCoupe said:
So if you reread what Noobz was saying he was merely asking if anyone knew what it would take to swap to a carb setup to get you another path. I happen to agree with him as my 83 T-Brid was CFI and it was a pile of crap. Switched it to a carb when it got the warmed up 306 and T5 and never looked back.

CFI to Carb swap help! Please god!

Okay. I have a 1985 Mustang GT convertible with an AOD tranny. I can't stand it! I want to go carb so bad but can't find a good, COMPLETE parts list or how to. I've seen tons of little tid bits here and there and peoples GUESSES but I want someone who KNOWS what they're talking about. I know I...
stangnet.com

Lots of threads on the Mustang sites about swapping. The CFI cars have an intank lift pump and then an external high pressure pump on the rear frame rail. From what I remember you can simply remove the high pressure pump and the lift pump will provide enough pressure and volume for a carbureted car. You will need a fuel pressure regulator. The only reason I know this is a guy over on a Thunderbird forum did this with a mild 351W and it ran fine.
Click to expand...

AeroCoupe said:
Can you post a picture of what you have?
Click to expand...
 

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M

Myfirstgt

Member
Oct 9, 2023
16
6
13
Fla
Oct 28, 2023
#29
  • Oct 28, 2023
  • #29
AeroCoupe said:
Can you post a picture of what you have?
Click to expand...
 

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M

Myfirstgt

Member
Oct 9, 2023
16
6
13
Fla
Oct 28, 2023
#30
  • Oct 28, 2023
  • #30
AeroCoupe said:
Can you post a picture of what you have?
Click to expand...
 

Attachments

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M

Myfirstgt

Member
Oct 9, 2023
16
6
13
Fla
Oct 28, 2023
#31
  • Oct 28, 2023
  • #31
AeroCoupe said:
So if you reread what Noobz was saying he was merely asking if anyone knew what it would take to swap to a carb setup to get you another path. I happen to agree with him as my 83 T-Brid was CFI and it was a pile of crap. Switched it to a carb when it got the warmed up 306 and T5 and never looked back.

CFI to Carb swap help! Please god!

Okay. I have a 1985 Mustang GT convertible with an AOD tranny. I can't stand it! I want to go carb so bad but can't find a good, COMPLETE parts list or how to. I've seen tons of little tid bits here and there and peoples GUESSES but I want someone who KNOWS what they're talking about. I know I...
stangnet.com

Lots of threads on the Mustang sites about swapping. The CFI cars have an intank lift pump and then an external high pressure pump on the rear frame rail. From what I remember you can simply remove the high pressure pump and the lift pump will provide enough pressure and volume for a carbureted car. You will need a fuel pressure regulator. The only reason I know this is a guy over on a Thunderbird forum did this with a mild 351W and it ran fine.
Click to expand...
 

Attachments

  • IMG_20231028_111833139.webp
    134.7 KB · Views: 87
M

mustangdan04

Member
Oct 13, 2023
2
1
13
Connecticut
Oct 28, 2023
#32
  • Oct 28, 2023
  • #32
AeroCoupe said:
So if you reread what Noobz was saying he was merely asking if anyone knew what it would take to swap to a carb setup to get you another path. I happen to agree with him as my 83 T-Brid was CFI and it was a pile of crap. Switched it to a carb when it got the warmed up 306 and T5 and never looked back.

CFI to Carb swap help! Please god!

Okay. I have a 1985 Mustang GT convertible with an AOD tranny. I can't stand it! I want to go carb so bad but can't find a good, COMPLETE parts list or how to. I've seen tons of little tid bits here and there and peoples GUESSES but I want someone who KNOWS what they're talking about. I know I...
stangnet.com

Lots of threads on the Mustang sites about swapping. The CFI cars have an intank lift pump and then an external high pressure pump on the rear frame rail. From what I remember you can simply remove the high pressure pump and the lift pump will provide enough pressure and volume for a carbureted car. You will need a fuel pressure regulator. The only reason I know this is a guy over on a Thunderbird forum did this with a mild 351W and it ran fine.
Click to expand...
I really thought he was concerned about the rough idle and I gave some advice on how to fix it I



don't think he always had to be replacing parts
 
Reactions: Mcmahst

Mcmahst

5 Year Member
Jan 19, 2021
681
267
83
Laguna Woods CA, fort Mohave AZ
Oct 28, 2023
#33
  • Oct 28, 2023
  • #33
Great car pics. How about pics of the top of the engine with the air cleaner removed. Just to see the overall condition of the systems. Also, have you had a chance to check the engine vacuum and put a ECU tester on it?
 
M

Myfirstgt

Member
Oct 9, 2023
16
6
13
Fla
Oct 28, 2023
#34
  • Oct 28, 2023
  • #34
Unfortunately I have not had time to do that. Gotta work and be a responsible senior adult first. lol Sorta funny cause when I took the pics this morning the girl says… maybe you should have sent pictures under the hood!! I just looked at her and took another drink of my coffee. she’s smarter than she looks. I’ll take some when I get back to the house.
 
Reactions: 90sickfox, Mcmahst, Noobz347 and 1 other person

Potomus Pete

I'm still waiting for the fully nude shots
5 Year Member
Mar 7, 2019
3,308
1,223
153
Sarasota Florida
Oct 28, 2023
#35
  • Oct 28, 2023
  • #35
Whom ever this cars owner is needs to post up. You got a good one so lets see it.
 

85GTStangGuy

5 Year Member
May 19, 2021
1,001
625
133
Jax, Florida
Oct 28, 2023
#36
  • Oct 28, 2023
  • #36
Myfirstgt said:
she’s smarter than she looks.
Click to expand...
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,096
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234
Box behind Walmart
Oct 28, 2023
#37
  • Oct 28, 2023
  • #37
Myfirstgt said:
Unfortunately I have not had time to do that. Gotta work and be a responsible senior adult first. lol Sorta funny cause when I took the pics this morning the girl says… maybe you should have sent pictures under the hood!! I just looked at her and took another drink of my coffee. she’s smarter than she looks. I’ll take some when I get back to the house.
Click to expand...
Where's her account? We'll have this thing fixed in a jiffy.
 
Reactions: qikgts and Mcmahst

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
5,466
2,899
173
Florida
Oct 29, 2023
#38
  • Oct 29, 2023
  • #38
Myfirstgt said:
she’s smarter than she looks.
Click to expand...
Good looking and Blonde?
 
M

mustangdan04

Member
Oct 13, 2023
2
1
13
Connecticut
Oct 29, 2023
#39
  • Oct 29, 2023
  • #39
I don't think I understand
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,926
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polk county florida
Oct 29, 2023
#40
  • Oct 29, 2023
  • #40
mustangdan04 said:
I don't think I understand
Click to expand...
Don't get him started he's a member of 'The Women Bashers Club'
 
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