jlong956

hey guys, im new to the forum and the mustang world in general. this past spring i bought an 03 GT. im having an intermittent starting problem. what happens is when i get in and turn the key, the engine cranks and seems to fire once or twice and dies out. as if you start it and turn the key right off again. it only happens like every third time i start it but its completly random when it happens. hot day cold day, engine warm engine cold, full tank or near empty. ive turnd the key to the on position to let the fuel pump run before i start it and that has no effect on it either. i just cant seem to figure this out! some days itll start up no problem all day til i stop and get some gas, then when everyone is lookin at me when i get in, it stalls on me once or twice befor itll stay running(very embarrassing!). its never not started on me but its happend 3-4 times in a row before it stays running. when it starts she just purrs no misfire, or rough idle, nothing.

when i first bought the car it kicked the engine light after the first 500mis of ownership. code was cam shaft position sensor bank one. replaced it with an aftermarket sensor and the light has come on and off a couple times since then with the same code. it when off recently and hasnt been back since.

any ideas???

i can probably post a video if that would help any diagnosis.

thanks for any and all help!!

-Justin

o mustang o

My 99 gt was having very similar problems. A new Fuel pump and Idle air control valve fixed the issue.

cliffyk

How many miles on it, when were the spark plugs last changed, when were the COP boots last inspected?

jlong956

sorry to be a newb but im guna have to ask a few dumb questions here...

i was considering a new fuel pump. but a buddy at work said it sounds like its got fuel but no spark. when i bought the car it had another 03' 4.6 sohc motor installed in it because the original got hydro-locked from sucking up water...thats the story i got when i bought the car. the odo says 72k the engines got 58k. i replaced the intake manifold with ford racing's PI intake and with i did that put brandy new iridium plugs and are gapped correctly.

where is the fuel pump located? im guessing in the tank? and 'COP' boots?

GriffinGT

Im having the same problem. I replaced the senor and the light is still on. Im looking for help also.

jlong956

which sensor did you replace? the cam shaft position sensor? did you buy a ford or aftermarket?

GriffinGT

After market. and it was the cam shatft.

GriffinGT

I bought a new alternator and the light is gone and car starts better. Ill keep in touch to make sure it stays gone. I bought steeda Underdrive Pullys and I believe that's what started all of this. My car only has 23k miles and crazy for the alt to go so quickly.

cliffyk

What are your normal driving habits--short drives, long drives. miles per day, etc?

FlamingoGT

The COP boots are the boots between the COPs (Coil On Plug) and the spark plugs; think of it as the spark plug boot of old.