engine sputtering/missing

What does it do under WOT?
Is it consistent throughout the RPM, or get worse/better as RPM goes up?

Dim lights at idle is normal to an extent, it could be a bad alternator or voltage regulator if it is a drastic change.

what kind of mustang is it? Plugs/wires, grounded plug wire, bad gas (water), all could be causes, start simple, if your on 7 cylinders your lights may be dim cause your idle is low...

V_Stud said:

Speaking of WOT,
it doesnt matter how much i accelerate, it'll keep sputtering until it just randomly goes finally after a few seconds.

It is a pretty drastic change in brightness, but if this is normal..are you saying my problem ISNT electrical related?
Thanks
TREY

Click to expand...

i am having a problem in the neighborhood of what you are, so i read your thread. for your dimming problem: given the sputtering problems, are you sure your idle has not dropped a little bit? stock idle is ~650 rpm. were it to drop even a little as a result of your car's ailment, that would exacerbate the voltage drop the alternator experiences. the stock tach is not accurate enough to really tell if the idle has dropped (it's really not accurate in increments under 100 rpm, hence the need for a tuning tach when doing mods, setting idle, etc). you could always adjust the idle up a little (and readjust the tps once you are done, as you will have jacked the "at rest" voltage of the tps). what idle are you at (roughly)? a fair number of folks run ~1K rpm at idle.

good luck.