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Engine 5.0 Running Rough (1990)

  • Thread starter Thread starter spliffmode
  • Start date Start date Apr 28, 2019
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    1990 mustang 5.0 fox fox body 5.0
S

spliffmode

New Member
Apr 28, 2019
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Lancaster, CA
Apr 28, 2019
#1
  • Apr 28, 2019
  • #1
Mustang running very rough Any Help Greatly Appreciated.
i did upgrade to 24lb injectors but problem was there prior to the change as well
changed : distributor cap and rotor, also change the coil, spark plugs + wires, fuel filter, fuel pump, IAC, EGR,

still can't figure out the problem. also noticed the EGR + smog items dont have vacuum lines. could that be the issue?
also need help with a full diagram of the vacuum lines (preferably a video)

also runs really rocky/rough on step of the pedal may be due to stretched throttle cable but was running like so before it became stretched, could it be a block in the exhaust such as a catalytic converter? as that bottom piece of metal did shave off at one point (car is pretty low) i ask because it pops on deceleration and if i revv it (or try too shall i say) it also pops it sounds likes its coming from underneath me/exhaust area.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
Apr 29, 2019
#2
  • Apr 29, 2019
  • #2
I kinda giggled at the screen name, cool.
Ok, first thing you can do is check for codes. Here is a link to a 'surging idle checklist' that will help you, start at the top and do it step by step.
http://forums.stangnet.com/showthread.php?t=698148
Don't skip around, each step is dependent on the result of the step before. It has a diagram for the vacuum line too.
Is there any modifications other than the injectors? I hope you saved the 19 lb injectors.
 
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