Fox Wifes 1993 LX 5.0 dies after replacing ignition parts

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Warhorse85

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Jun 17, 2023

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Aug 16, 2025

#1

• Aug 16, 2025

• #1

Hello everyone, I'm having trouble figuring out why my wifes 1993 LX 5.0 dies while idling after replacing some ignition parts. The parts I have replaced are the MAF, TFI module and ignition coil. EGR was replaced last year. Car starts and runs great but after idling for a bit it surges for a couple of seconds then goes back to idling normal then about 5-10 seconds later it just dies as if someone turned the ignition key off. It will instantly restart and idle with no issue for a few minutes and do the exact same thing. I did notice that there is a loud buzzing noise coming from the EGR area while it's idling. Any help would be greatly appreciated.

 

gkomo

now i can hopefully expect to receive the shaft

Aug 2, 2024

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Aug 16, 2025

#2

• Aug 16, 2025

• #2

What TFI module did you use and did you use thermal grease in the mating surface?

 

W

Warhorse85

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#3

• Aug 16, 2025

• #3

gkomo said:

What TFI module did you use and did you use thermal grease in the mating surface?

Click to expand...

Motorcraft and no I did not use thermal grease

 

KRUISR

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Apr 16, 2015

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#4

• Aug 16, 2025

• #4

Fuel pressure regulator sticking or not cycling right?

 

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Warhorse85

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Jun 17, 2023

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#5

• Aug 16, 2025

• #5

KRUISR said:

Fuel pressure regulator sticking or not cycling right?

Click to expand...

No clue, no idea how to check. Definitely not a fuel issue

 

gkomo

now i can hopefully expect to receive the shaft

Aug 2, 2024

2,205

1,440

133

San Diego, CA

Aug 16, 2025

#6

• Aug 16, 2025

• #6

Warhorse85 said:

Motorcraft and no I did not use thermal grease

Click to expand...

TFI could be getting too hot or something and causing issues… I believe they need thermal grease on the mating surface.

 

S

slow84lx

clean it good before insertion

Jul 3, 2005

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#7

• Aug 17, 2025

• #7

Just curious, why did you change these parts? Were you trying to resolve a problem? Do you still have the parts that you took off?

My first thought is to put the TFI that you took off back on and see if that solves the current problem.

 

Reactions: 2000xp8

limp

wrap a little cheese around it and its a done

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#8

• Aug 17, 2025

• #8

OH man, I bet you are on the $hit list at home

 

AeroCoupe

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

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#9

• Aug 17, 2025

• #9

@Noobz347 - can you merge this thread with the one over in the Fox 5.0 tech forum?

 

Noobz347

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

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#10

• Aug 17, 2025

• #10

AeroCoupe said:

@Noobz347 - can you merge this thread with the one over in the Fox 5.0 tech forum?

Click to expand...

I'll close this one since the merge will make a mess.

W

Thread '1993 LX 5.0 dies after ignition parts replacement'

Aug 16, 2025

Hello everyone, I'm having trouble figuring out why my wifes 1993 LX 5.0 dies while idling after replacing some ignition parts. The parts I have replaced are the MAF, TFI module and ignition coil. EGR was replaced last year. Car starts and runs great but after idling for a bit it surges for a couple of seconds then goes back to idling normal then about 5-10 seconds later it just dies as if someone turned the ignition key off. It will instantly restart and idle with no issue for a few minutes and do the exact same thing. I did notice that there is a loud buzzing noise coming from the EGR...

• Warhorse85