Fuel Pump

[89tang]

Hello, I have an 89 Mustang 2.3L and am not getting any power to the fuel pump when the outside temperature is below 32 degrees but, as soon as it warms up the car will start just fine. Is there anyone that can help me solve this mystery?

[noctorum]

This is really just a shot in the dark, but you might have water in your tank. Water freezes below 32 degrees F, and it could be clogging your pump/lines. Couldn't hurt to flush your tank and put all fresh gas in.

[89tang]

There is no power reaching the pump at all during this problem, I forgot to mention that it does this 95% of the time.

[dellga]

Another shot in the dark, try attaching the ground wire for the pump to a different location. If it's the kind that just fits under one of the bolt lugs, then extend the wire to a more reliable ground location.

[noctorum]

Eh, irregardless, I'd still recommend flushing your tank, couldn't hurt

And yes, check all of your wires. Look for any signs of corrosion, or if any are loose, replace them.

[89tang]

I TOOK THE MUSTANG TO THE FORD DEALER THIS MORNING AND THEY DID A DIAGNOSTIC ON IT, THEY DETERMINED THAT IT WAS EITHER THE PCM GETTING MOISTURE IN IT AND FREEZING OR THAT THE FUEL PUMP WAS GOING BAD. I DID NOT LET THEM FIX IT BECAUSE THE MECHANIC SAID THAT IT WAS A GUESSING GAME TRYING TO GET IT REPAIRED AND THAT HE STILLED DID NOT UNDERSTAND HOW THAT IT ONLY DOES IT WHEN COLD WEATHER COMES AROUND. FUNNY THING IS THAT WHEN I INSTALLED THE NEW BATTERY THAT IT STARTED FINE FOR A WEEK AND A HALF WHILE IT WAS DOWN TO 10 DEGREES. I GUESS THE NEXT STEP IS TO DROP THE TANK AND FLUSH IT.

[89tang]

Problem Solved: The fuel pump inertia switch was bad. I bypassed it and it starts great now, I just need to find another Inertia Switch. Thanks Fellas for all your input and help.