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How do you know a TFI may be going out?

  • Thread starter Thread starter 88 Fox GT
  • Start date Start date Aug 9, 2005

88 Fox GT

Active Member
Nov 18, 2002
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Iowa
Aug 9, 2005
#1
  • Aug 9, 2005
  • #1
This isn't my Mustang, but rather my 5.0 truck. It won't run. I drove it the other day and it ran just fine all the way to point A to B and back. I parked it in front of my driveway and when I went to start it to put it in the driveway, she wouldn't fire. A few hours later, she fired right up and ran fine. Now it won't fire again. I checked to see if the coil was sparking and it wasn't. So, I tried another coil that did work and it didn't spark either. Could my TFI be going out on this truck? Would a bad TFI keep the coil from sparking? Thanks.
 

jrichker

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Aug 9, 2005
#2
  • Aug 9, 2005
  • #2
No working TFI = no spark, no matter how hard you try.

My TFI recently died in a similar manner. The engine fired up and promptly died. It refused to start from that point on until I replaced the TFI.
 

88 Fox GT

Active Member
Nov 18, 2002
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Iowa
Aug 9, 2005
#3
  • Aug 9, 2005
  • #3
I think it's probably the TFI, but the parts house said they can test mine for me and a new one is like $30. So, I will probably go and have it tested tomorrow. I imagine I will probably end up buying a new one cause I know it's fairly common for these to go out and this one has 170k miles on it. Thanks.
 

z9_87

New Member
Apr 16, 2004
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Urbana, IL
Aug 9, 2005
#4
  • Aug 9, 2005
  • #4
170k, yeah replace it. These things suck, they can go out while you're driving down the road... at 70mph, just die.
 

tripwhite93

New Member
Sep 15, 2004
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Aug 10, 2005
#5
  • Aug 10, 2005
  • #5
Check out this web site. http://www.dccurrent.com/fbt/tps.htm
 

z9_87

New Member
Apr 16, 2004
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Urbana, IL
Aug 10, 2005
#6
  • Aug 10, 2005
  • #6
Check out this web site. http://www.dccurrent.com/fbt/tps.htm
Click to expand...

TFI, the thing on the side of the distributor, not the TPS.
 
B

bcd

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Jun 23, 2005
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arab al
Aug 10, 2005
#7
  • Aug 10, 2005
  • #7
they can test a tfi at advanced auto parts
 
G

gork1rogues

New Member
Oct 2, 2003
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Aug 10, 2005
#8
  • Aug 10, 2005
  • #8
My F150 would do the same thing. Start up fine then run for a while, shut off, no start up, wait a while, would start up, then it finally wouldn't start anymore. Replaced the TFI and all is well.
 

tripwhite93

New Member
Sep 15, 2004
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Aug 11, 2005
#9
  • Aug 11, 2005
  • #9
z9_87 said:
TFI, the thing on the side of the distributor, not the TPS.
Click to expand...
OOPS your right
 

RsStanG1987

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Aug 11, 2005
#10
  • Aug 11, 2005
  • #10
My friends car needed one the car would start and run fine, But once it warmed up it would cut out. He replaced and the problem went away.
 
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