Can Bad Alternator Cause Hesitation/Sputting Under Hard Acceleration??

[03VNM]

Hey guys,

So I am still trying to pinpoint why my 2003 Cobra is sputtering/cutting out under hard acceleration. The car has a 2.9 upper and 6 lbs lower, 60 lbs injectors, Kenne Bell BAP, CAI, Midlength headers and catted X pipe. I was out driving it yesterday and the radio just turned off which lead me to believe I may have alternator issues, which may solve the mystery. Would a failing alternator not be able to run the BAP, therefore, not supply the 60 lbs injectors with needed fuel demands under hard acceleration?

 

[rickrubin2]

Well if radio cuts off that is a sign that alternator is going bad as well as the flickering battery light. Which I think The radio cutting off is a sign of low voltage so if so then your fuel pumps are probably suffering some what. Try replacing plugs too that will make it spit under load.


On a side note I had a similar issue with radio cutting off and would eventually die when battery goes dead.

 

[03VNM]

Well if radio cuts off that is a sign that alternator is going bad as well as the flickering battery light. Which I think The radio cutting off is a sign of low voltage so if so then your fuel pumps are probably suffering some what. Try replacing plugs too that will make it spit under load.


On a side note I had a similar issue with radio cutting off and would eventually die when battery goes dead.

Thanks for the info! I did notice the red battery light come on when I turned on the cooling fans. What alternator are you guys running with cars drawing a lot of power due to BAPs, Fans, Gauges ect? I'm thinking I need either a 160 or 200 amp alternator to support my modifications.

 

[rickrubin2]

I run a 200 amp

 

[03VNM]

I run a 200 amp

Yea, that's what I was thinking... Apparently there is a 200 amp in there, but I have concerns if there really is. I'll take a picture tonight and post it up, maybe someone here can verify what I have. It may be externally regulated since I see little red box next to the fuse box that says "200 amp" with an enclosed wire going to alternator.

Thanks for your input, really appreciated!

 

[03VNM]

Has anyone ever had a voltage regulator go bad? Anyway to check to make sure it is functioning?

 

[speeddemon2000]

Yes if you are dropping voltage that will cause less fuel flow and a potential lean condition. Not good.

Radio going off is a sign.

What is your voltage under full throttle? You want to see between 13 and 14 volts. Anything below is a potential issue.

You can view it using your guage cluster:

http://www.mustangworld.com/ourpics/fcar/dtcodes.htm

If you are not dropping voltage I bet you have an issue with one of your coil packs.

Ran into that one before. Only hit at full throttle. Replace all the coil packs and bingo problem solved.