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89 Mustangs not starting (fuel pump not priming)

  • Thread starter Thread starter sggarcia
  • Start date Start date Jun 2, 2022
S

sggarcia

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Jun 2, 2022
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Jun 2, 2022
#1
  • Jun 2, 2022
  • #1
Thank you for allowing me on this forum. I hope that I can get some advice from all the pro's here. I have two mustangs, both 89's 302 stock engines that are doing exactly the same thing. They were working and then I parked them for a while and now that I went to turn them on, they both crank but it wont start. I used to hear the fuel pumps priming but now I dont. They used to work fine with no issues. One one, I checked power to the relay under the drivers seat and I get power. I checked power to the inertia cables and I get power to that too. Is there anything else that I could check? I had heard that there might be a fuse by the brake booster but I am not sure. If there is one, where would it be? Thank you for all your input. It is much appreciated.
 

General karthief

wonder how much it would cost to ship you a pair
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#2
  • Jun 2, 2022
  • #2

Cranks OK, but No Start Checklist for Fuel Injected Mustangs

Cranks OK, but No Start Checklist for Fuel Injected 5.0 Mustangs model years 1986-1995 A word about this checklist before you start: it is arranged in a specific order to put the most likely failure items first. That will save you time, energy and money. Start at the top of the list and work...
www.stangnet.com
 
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Gs1987GT

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Jun 3, 2022
#3
  • Jun 3, 2022
  • #3
Follow the checklist posted by general step by step, dont skip any steps. You will find the issue if you do.

I will say if you have two 89 mustang's and they both do the exact same thing that is quite odd. What is the condition of the batteries? Age? Voltage? Load tested? You should hear the fuel pump prime everytime you cycle the key. That is an issue. Will it attempt to fire if you spray a little either in the throttle body?
 
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sggarcia

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Jun 2, 2022
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Jun 3, 2022
#4
  • Jun 3, 2022
  • #4
Gs1987GT said:
Follow the checklist posted by general step by step, dont skip any steps. You will find the issue if you do.

I will say if you have two 89 mustang's and they both do the exact same thing that is quite odd. What is the condition of the batteries? Age? Voltage? Load tested? You should hear the fuel pump prime everytime you cycle the key. That is an issue. Will it attempt to fire if you spray a little either in the throttle body?
Click to expand...
Gs1987GT said:
Follow the checklist posted by general step by step, dont skip any steps. You will find the issue if you do.

I will say if you have two 89 mustang's and they both do the exact same thing that is quite odd. What is the condition of the batteries? Age? Voltage? Load tested? You should hear the fuel pump prime everytime you cycle the key. That is an issue. Will it attempt to fire if you spray a little either in the throttle body?
Click to expand...
I have put a new battery on them and they both crank. I will check the list by general. It is very strange that both were working and I could hear the pump being primed every time I would turn the ignition switch on but then I parked them for a several months and then both started having the same issues. Very strange to me. I am hoping to spend some time this weekend and try this check list and see if they will start with some fluid. Thank you.
 

JD1964

there is enough sticking out to grab on to
15 Year Member
Jun 28, 2013
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Jun 3, 2022
#5
  • Jun 3, 2022
  • #5
Sometimes when the pump won’t prime, it’s caused by failing capacitors in the ECU. The timed (2-3 seconds) prime function is controlled by the ECU. You don’t have to have high mileage for the capacitors to fail. They do it with age.
 
C

chrlsful

Active Member
Mar 6, 2021
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Lawrence Swamp, S.Amherst, MA
Jun 6, 2022
#6
  • Jun 6, 2022
  • #6
is this the same Q on 2 threads? Confusing if so.
If not, ck other thread for ideas...
 
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