ironwarrior

Hello..
I just started encountering starting problems with my 2000 GT Mustang.. Has 50k miles. It is stock with no mods added.
I added a new aftermarket fuel pump and filter @ 32,000 miles due to a clogged pump at the time and car would not start. This fixed that issue and has been running fine until now @ 50k miles.
I also recently changed the air filter with a stock replacement and have had no problems since then.

Problem:
After the car has been sitting overnight or all day it takes about 5-6 cranks before it will start. I tried pumping the gas and it bogged and slightly back fired then started. But if I don't pump the gas it will start with no backfire just takes these extra cranks.
After it starts I notice no issues in driving. It idles fine, drives fine through all ranges and notice no issues.

Today I let it sit overnight and cranked it and it started at about 2-3 cranks. But before this problem it always started instantly on the 1st crank,
so I know there is some issue going on. It is strange that it runs fine after it starts.

Can you please help me fix this issue...
I ordered a motorcraft fuel filter to try and bought a fuel pressure gauge today.
I will test this weekend. I heard that you need yellow teflon tape for the fittings on the fuel pressure gauge so I need to get that too.

Z28KLR

Excessive cranking before it starts can often be attributed to fuel pressure leakdown. The fuel pump has a check valve that holds pressure in the lines from the initial pressurization that occurs when you turn the key to the "On/Run" position. That check valve can sometimes fail.

Try turning the key from Off to On/Run 2 or 3 times before attempting to crank the engine. If that seems to help then it goes a long way toward pointing at the fuel pump check valve as the culprit.

ironwarrior

Thank you very much Z28 for your response.
Your comment makes a lot of sense.
I have confirmed with full certainty that turning the key off and on 2 to 3 times before attempting to crank the engine allows me to start within 1-2 cranks (almost normal).
Without doing this, it takes maybe 4-5 cranks before it will start (Even more apparent after sitting for extended periods of time). I have been reading and it seems that many have had similar issues with the mustang fuel pumps.
I wonder why they are so unreliable. My car again is a 2000GT Mustang with only 50,000 original miles. I had the original OEM fuel pump go out after only 30,000 miles and had replaced it with an aftermarket fuel pump module assembly. The symptoms with that was different though, as it wouldn't start at all. I found that the pump filter had picked up a lot of sediment from the tank. I since have learned to avoid getting gas when the fuel tanker is present and refilling the stations pumps as they say it stirs up sediment. Originally I never gave that much thought, but it sure makes sense and I now look for that.

I will be ordering a new fuel pump this weekend. I already picked up a filter as well.
I will keep you posted to let you know if it fixed the issue...

Thanks again for your help.. appreciate it.

movielover40

Keep your gas tank above 1/4 tank.

Running tank low adds a lot more heat/wear to the fuel pump. Gas in the tank helps cool it.

Camster

1.I'd figure out some way to drain and flush out the tank.If you're doing the pump job,that should be easy enough.
2.I try to stick with OEM parts.
3.Pumping the pedal of a fuel injected car does nothing.