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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

breakin up???????

  • Thread starter Thread starter l3urnin0ut88
  • Start date Start date Feb 21, 2009

l3urnin0ut88

New Member
May 9, 2008
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Feb 21, 2009
#1
  • Feb 21, 2009
  • #1
question,,,today i installed 1.7 roller rockers,24lb injectors,c&l 73 mm mass air unit,and a bbk adjustable fuel pressure reg. on my 88 gt,i set the fuel at 38-40 lbs, whats happening now is at like 5000 rpm its breaking up,it did not do this before.,,any clues to why it is doing this..??????,,,it also has a gt-40 intake ,e303 cam,70mm throttle body,if this helps any,,,im confused,,,lol?
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
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Chicagoland
Feb 21, 2009
#2
  • Feb 21, 2009
  • #2
Does the C&L have the correct sample tube? Did you set the fuel pressure with the vacuum line off? Stupid question, I know, but it happens sometimes.
 

l3urnin0ut88

New Member
May 9, 2008
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Feb 21, 2009
#3
  • Feb 21, 2009
  • #3
yes it has a brand new sample tube for 24lb injectors,and i did set it with the vacum line of,,,it seems to work great other then it breaks up aaround 5000 rpm,,,kinda sounds like a rev limiter??
 

jrichker

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Feb 22, 2009
#4
  • Feb 22, 2009
  • #4
The TFI module mounted on the distributor is usually the culprit for a high speed miss on a warm engine. If the problem does not occur when the engine is cold, the TFI module is definitely suspect. You may need a special socket to remove the TFI module, but most auto parts stores will have one for $5-$7.

View attachment 269634

See Automotive Tools Specialty | Auto Mechanic & Technician Diagnostic, Testing Equipment | Thexton

Or you can grind down the outside of a 7/32" deep socket untill it fits.
 
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