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Electrical 89 no injector pulse and fuel pump constantly running

  • Thread starter Thread starter Taz_Crawford
  • Start date Start date Feb 2, 2019
  • Tags Tags
    electrical help injector

Taz_Crawford

Member
Feb 2, 2019
8
1
13
Columbia, SC
Feb 2, 2019
#1
  • Feb 2, 2019
  • #1
I am new here but I have looked through all these forums trying to find an answer to my problem. I own a 89 hatch 5.0 5 speed. I recently purchased it (Saturday night) not running but quickly got it running (Sunday morning) with a fuel pump, fuel filter, ignition switch and battery. I drove it all Sunday working out a few kinks and getting used to the car (Its my first fox) and it ran good. I let it sit over night Sunday and when i woke up Monday, it didn't run. i went to work all day came home and found i had spark but the injectors wouldn't fire. I started at the ignition switch because this was similar to when it was broken but everything seemed to be ok. then I took one injector connection off and tested for power. it has 12v at the red wire. Next I inspected the computer connections and everything looked tight without water damage. The ground on the inner fender near the battery is also connected and has no corrosion. What else do i need to check? Am i over looking something? Thanks in advance!
 

General karthief

wonder how much it would cost to ship you a pair
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#2
  • Feb 2, 2019
  • #2
https://www.stangnet.com/mustang-fo...start-checklist-fuel-injected-mustangs.787471
This shows you how to check for codes and the proper procedures to find your problem, start at the top and do it step by step, don't skip around.
 

Taz_Crawford

Member
Feb 2, 2019
8
1
13
Columbia, SC
Feb 3, 2019
#3
  • Feb 3, 2019
  • #3
Ok so I got to step #3 and the car started and now continues to start and idle but its very rough and wants to die when i rev it up. I am continuing to test fuel related issues and ill keep this updated but another issue is the fuel pump wont turn off with the key in run. could this be causing the rough idle?
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Feb 3, 2019
#4
  • Feb 3, 2019
  • #4
No. Once the engine starts, the fuel pump runs continuously.
Or do you mean ignition on only? That's an EEC problem.
 

Taz_Crawford

Member
Feb 2, 2019
8
1
13
Columbia, SC
Feb 3, 2019
#5
  • Feb 3, 2019
  • #5
key in run engine off the pump runs constantly. is there a way to check the EEC?
 
S

sd331

Member
Sep 9, 2008
69
19
18
NJ
Feb 3, 2019
#6
  • Feb 3, 2019
  • #6
pull out the eec and check the capacitors..i bet there bad..and they need to be replaced
 

Taz_Crawford

Member
Feb 2, 2019
8
1
13
Columbia, SC
Feb 3, 2019
#7
  • Feb 3, 2019
  • #7
sd331 said:
pull the eec and check the capacitors..i bet there bad..and need to be replaced
Click to expand...
can you replace just the compacitors? and how do i pull the EEC?
 
S

sd331

Member
Sep 9, 2008
69
19
18
NJ
Feb 3, 2019
#8
  • Feb 3, 2019
  • #8
yes you can replace the caps..there are 3 of them..do a search on eec cap replacment and pulling out the eec..you will learn more on the web than i can explain..also after you get the eec repaired and start the car the car is going to run rough..because the eec is relearning..let it run for a while..after shutting it down and restarting and run it a few times..it might take a couple of days then the car should idle and drive as normal..unless theres something else causing a problem
 

Taz_Crawford

Member
Feb 2, 2019
8
1
13
Columbia, SC
Feb 3, 2019
#9
  • Feb 3, 2019
  • #9
ok. Thank you for the input!
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,904
10,558
203
polk county florida
Feb 3, 2019
#10
  • Feb 3, 2019
  • #10
Continue with the checklist or switch to the surging idle checklist. You have to be methodical in diagnosing these cars, you can chase your tail and waste time and money jumping around
 
1

1992Stocker

New Member
Feb 3, 2019
5
0
1
Florida
Feb 3, 2019
#11
  • Feb 3, 2019
  • #11
Taz_Crawford said:
can you replace just the compacitors? and how do i pull the EEC?
Click to expand...
I sent mine to The EFI Guy in Colorado. Charges me $50. (35 for parts and lobor and 15 to ship it back).
 

Taz_Crawford

Member
Feb 2, 2019
8
1
13
Columbia, SC
Feb 4, 2019
#12
  • Feb 4, 2019
  • #12
Ok so update..... continuing the checklist i went and got a noid light and hooked it up. The light stayed on and the car continued to run like crap. I then pulled the computer so i could inspect and see how the connections looked, they were corroded so i cleaned and put everything back. THEN I checked for codes because i noticed the check engine light on and while i was doing that my brother gets in the car, kicks the computer on the floorboard, and everything works. it ran, idled, and drove fine. I'm leaning twords this being a computer issue... after all this I can still drive the car so long as i wiggle the computer around a little
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,904
10,558
203
polk county florida
Feb 4, 2019
#13
  • Feb 4, 2019
  • #13
Pull the connector from the computer and clean the pins with electrical cleaner and make sure the pins are tight when connected back.
 

Taz_Crawford

Member
Feb 2, 2019
8
1
13
Columbia, SC
Feb 5, 2019
#14
  • Feb 5, 2019
  • #14
OK Ill post results when Im done
 
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