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1984 5.0 throttle body convertible stalls when warm

  • Thread starter Thread starter velocity5
  • Start date Start date Apr 25, 2019
V

velocity5

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Apr 25, 2019
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#1
  • Apr 25, 2019
  • #1
Car starts and idles perfect for 10 minutes. Before the thermostat even opens it then surges and blows black smoke. It smells rich and dies. I have to hold in the throttle to restart.
Long time owner states it has been looked at years ago and nobody could figure it out. She just puts it in neutral at stop lights to keep it running.
The car is in great shape otherwise. All emission hoses are there and hooked up. Where should I start?
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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Apr 25, 2019
#2
  • Apr 25, 2019
  • #2
Is the engine coolant sensor hooked up ? What year is your car ?
 

General karthief

wonder how much it would cost to ship you a pair
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Apr 25, 2019
#3
  • Apr 25, 2019
  • #3
84 with a throttle body? Is it cfi or was it converted?
maybe a picture would help.
 
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velocity5

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#4
  • Apr 25, 2019
  • #4
General karthief said:
84 with a throttle body? Is it cfi or was it converted?
maybe a picture would help.
Click to expand...
Car is factory. Sorry I don't know what cfi is. It looks like this but no a/c .
 
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velocity5

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#5
  • Apr 25, 2019
  • #5
90sickfox said:
Is the engine coolant sensor hooked up ? What year is your car ?
Click to expand...
1984. Everything appears to be plugged in.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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#6
  • Apr 25, 2019
  • #6
Yank the air cleaner off, I think you will find a carburetor under there.
 
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velocity5

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#7
  • Apr 25, 2019
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I am going out of town for a week so I will check it when I get back. I always thought it was a tbi. It always starts right up cold without pumping the gas.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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Apr 26, 2019
#8
  • Apr 26, 2019
  • #8
Let us know when you get back, we can start with a choke adjustment.
 

Mustang5L5

That is…until I whipped out my Bissell
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#9
  • Apr 26, 2019
  • #9
If it's a 5-spd it's a carb. If it's automatic, it's CFI. Really need to know what we dealing with first. Pictures help


CFI will say EFI on the valve cleaner. Carb will say 4V like the pic above
 
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velocity5

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#10
  • May 2, 2019
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I am back. Thanks or the help. I will check it asap and take a pic
 
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velocity5

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#11
  • May 3, 2019
  • #11
Mustang5L5 said:
If it's a 5-spd it's a carb. If it's automatic, it's CFI. Really need to know what we dealing with first. Pictures help


CFI will say EFI on the valve cleaner. Carb will say 4V like the pic above
Click to expand...
Looked at it today. It says EFI like the above pic. it is an automatic.
Owner informed me the catalytic converter was removed years ago. It also has had 2 brains swapped out trying to fix the issue.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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May 3, 2019
#12
  • May 3, 2019
  • #12
So it's CFI.

Which means it's eec-4 and you can pull codes. Locate the test plug which might be on the drivers rear of the engine bay near the wiper motor.

There's a sticky at the top of the tech page explaining how to pull codes. You'll need to use the test light method, or buy an innova 3145 meter for $20.

I'd locate that test plug first
 
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