Hard to start when hot

[Goldmember]

If I get the car up to temperature and then try to start it after sitting for a short time, the car will crank fast but not start. If I turn the key to on for a few seconds, then try again, it'll come back to life. Runs fine otherwise, doesn't happen after sitting overnight or when engine is cool. Ideas? I think fuel pump (and hope not)

 

[MustangChris]

hm.

ideas:
you're not letting the fuel pump "charge" the system before starting it (I always let my fuel pump click off after turning the key to "on" before starting the car)
hot fuel pump
hot starter

do you have long tube headers?

 

[CC'S95GT]

Might be the pmp. Test it and let us know what it's putting out. Might be something as simple as a fuel filter. When was the last time it was changed?

 

[LilRoush]

Just a random thought... how clean is your airfilter?
I've seen this happen to Mustangs that have a dirty/clogged filter.
Not sure why, but when it happend to me when I bought my 2000 way back when. One of the techs at the dealership said to check the airfilter. Sure enough...dirty as all get out. Put in a new $5 filter and didn't ever have the problem again.

 

[MustangChris]

Just a random thought... how clean is your airfilter?
I've seen this happen to Mustangs that have a dirty/clogged filter.
Not sure why, but when it happend to me when I bought my 2000 way back when. One of the techs at the dealership said to check the airfilter. Sure enough...dirty as all get out. Put in a new $5 filter and didn't ever have the problem again.

weird.

 

[OnyxCobra]

mine does this too but I think its a tuning issue. When my car would crank for a long time and not start it was the fuel pump but it would do it every time, not just when warm.

 

[MustangChris]

i have a feeling its a hot starter in the summer months.... personally.

 

[Goldmember]

i have a feeling its a hot starter in the summer months.... personally.

Got to thinking and you might be right on this, my other GT did the same thing. No long-tubes on it, hell even stock H-pipe. Sometimes I'll turn the key to on until the pump shuts off, have had other Fords where the pump lost pressure sitting overnight and needed to do that. Chalk it up to normal unless something gets worse.