[62GalaxieXL]

I'm having intermittent problems with the fuel pump or relay in my '98 Mustang V6.

Here's what I know:

• The car always starts on the first try but stalls after 1-2 seconds, so the fuel line is holding pressure
• I hear relay clicks coming from behind the passenger side kick panel but I have to cycle the ignition switch, on average, 10 times before I hear the fuel pump prime
• The inertia switch is not tripped
• Once started, it stays running. Re-start involves cycling the ignition until I hear the fuel pump prime and then it will start and run again
• I haven't checked the fuse, but since the fuel pump primes up sometimes, it can't be blown

I know the CCRM contains a (the only?) fuel pump relay among other things. The CCRM was replaced about 3 years ago for an A/C issue, so it is the newest component in this circuit but I'm not ruling out that it went bad already.

I have also searched auto parts websites for a 1998 V6 Mustang Fuel Pump Relay and see that there is one found (about $20) but I can find no reference to any Fuel Pump Relay in the Haynes manual outside of the CCRM.

Is there another fuel pump relay in the circuit other than the CCRM?

My guess is that it is a relay that is failing since once it makes contact, it maintains contact and runs fine. I'm leaning towards a failing CCRM but want to see if I've overlooked something else.

Any other suggestions as to what the problem may be or how to isolate it?

 

[wmburns]

Measure the power at the trunk mounted IFS switch. Cycle the key while monitoring the power. Best yet, monitor power while the fuel pump is still connected.

If this is a CCRM problem, there won't be any power (or the voltage will be low). If there is power every time the ignition switch is cycled, then likely this is a bad fuel pump.

And yes it is possible for a fuel pump to fail like this (IE comes and goes).

 

[62GalaxieXL]

Thanks. That should help me narrow it down.

It's the original fuel pump so I would suspect it before the CCRM but I have no experience with electric fuel pump failure so I didn't know if they would fail intermittently or all at once (and it runs just fine WHEN it runs).

 

[gearheadhick429]

just a thought. dont buy the cheaper parts. they always seem to have a high rate of failure and people rule them out since it was just replaced. i know you hate to hear this, but id go up to a ford dealer and get the factory parts. beleive me iv suffered this with numerous items.

just a suggestion i wish someone would have suggested to me years ago

 

[62GalaxieXL]

Just an update...

I finally got around to checking this out (the '98 Mustang is a 2nd car) and thought I had a bad pump because the voltages all checked out OK. I was about to drain the tank to change the fuel pump but I could only siphon about half of it, so I re-connected the electrical connections so I could run the rest of the tank out. Ever since then, the car has started every time. I'm going to give it a week or two of daily starts to verify it but it seems that it may have only been a case of dirty/fouled electrical connections preventing a good voltage level from reaching the pump. Good thing the new pump is still unopened and in the box!

The moral of the story is: Never overlook even the simplest of causes.