Electrical foxbody won't start without starter fluid, starts and runs fine for a few days

[dwalker93]

Hello, I am having a weird problem and I have looked all over but cannot find any solid answer.
I turn the key to the run position, all lights come on and fuel pump is running. (fuel filter was recently replaced) typically the fuel pump runs for a few seconds then goes off, that is when I start the car. But when I have this issue, the fuel pump does not stop running. The engine cranks over but will not start. I have been spraying a little bit of ether in the intake and it will start right up and run great. Then for the next few days the car will start and run perfectly, which makes me believe it is not a fuel or ignition problem. Sometimes I will have this problem daily and sometimes I will not have this problem for a week.
What has really been stumping me is that the car runs good and will start without an issue for at least the rest of the day. And why will the fuel pump not shut off when I am having this problem?

I have searched for weeks trying to find the answer to this issue.

 

[Blown88GT]

Someone else had the same problem here recently. The fuel pump not shutting off when the engine doesn't start is an ECU problem. This is what you want to search for. Usually, Google will find it better than the search engine here. This is true for most websites, unless they subscribe to Google Search which many don't because it costs them money.
Search Google with this phrase: ford mustang fuel pump will not shut off

 

[General karthief]

It's covered here:

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