Fuel Pump Takes Forever To Prime.

I have a 1993 Mustang LX 2.3L with a manual transmission and have owed it for about 2 years now.

When I purchased it from the previous owner is was bone stock and only two issues I noticed was the hearer core was leaking. I can’t remember if it was bypassed. I ended up replacing it. The other issue was that with the key on and engine running you could slightly adjust the key forward or back and the radio would turn on. Later I found out that this issue also controlled the windshield wipers and other electrical components even while the car was running. Unfortunately, this issue also meant you could adjust it incorrectly and the whole car could shut off. I replaced the ignition cylinder and that did not fix the problem.

Fast forward to about the last few months. I noticed the car would take a while to start (not turning over initially) and if I got it start it would bog and the rpms would fluctuate a little. After a short while it would settle down (warm up) and be just fine. I later realized that the issue with these start ups was due to the fuel pump taking a long while to prime. I would turn off everything and just listen to it. It would last between 7-10 secs before finishing it’s prime sequence. At that time I could turn the key and the car would start right up, no bogging no issues. At this time my thoughts were, “Fuel pump is going out.” The car was bone stock with little to no maintenance done so I have been doing it all as I go forward.

Yesterday I dropped the tank replaced the fuel pump (which IMO looked great), I went with the 155lph Walboro. Buttoned everything up and the car still took a long time to prime. No change. I took it for a drive and after getting 100 feet from my house the car died and would not start back up. I listened for the prime, you could here it prime and finish it’s sequence but it wouldn’t start back up. I ended up pushing it down the road out of traffic. I tried starting it several times and one of the fuel lines popped off the fuel filter. I guess the pressure from the 155lph was too much for the plastic clamp. I replaced the hose and used a new clamp I had with me! I waited about 10 minutes and then tried to he car, it fired right up. I slowly drove it back home and parked it.

1. I really want to know why it’s taking forever to finish it’s priming sequence. What would cause that? Faulty relay? If so, should I swap the CCRM because that’s what this year model has.
 
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Bad caps in the ECU or the ignition switch is failing (not the lock cylinder) would be my guess. You can visually inspect both and they are both known issues.

Igntion Switch Recall

Thread on the caps in the ECU
 
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Bad caps in the ECU or the ignition switch is failing (not the lock cylinder) would be my guess. You can visually inspect both and they are both known issues.

Igntion Switch Recall

Thread on the caps in the ECU
Thank you for your reply. I can’t believe the ignition switch never came to my mind. Of course that would help fix the ignition issue, not sure if it will fix the priming issue but def. worth a shot.
 
Bad caps in the ECU or the ignition switch is failing (not the lock cylinder) would be my guess. You can visually inspect both and they are both known issues.

Igntion Switch Recall

Thread on the caps in the ECU
To follow up, I replaced the ignition switch with a $16 part from Autozone. (sidenote: you will need a T27 tamper proof torx bit). After replacing this part everything is functioning again. The fuel pump is completing it’s priming sequence within a normal amount of time 2-5 seconds. And there are no issues with the key.

P.S. the old switch was pulling apart. I know some people say to just zip-tie these pieces together but for $16, i’ll just replace it!

Thank you for your time and assistance. Good luck everyone*
 
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