XXC

I'm having some old problems that I Used to have back in the day, I haven't really been driving my 5.0 because of gas prices and because of the problem I'm having.

what the car is doing is, When your driving, just holding the gas down normall.. out of no where the car will act as if you just shut it off and then turned it back on real quick, it literally seises and then goes again..

It feels as if it's just cutting of the gas for a seconed and then spiting it back in, and sometimes it will do it real violently and quickly.

It's not the carb because I've cleaned it and tuned the carb several times.. and I changed out the fuel filter.

I'm thinking that it's the fuel pump in the tank..

I havent' changed that out since I got the car so that's the only thing really that I see can be wrong.

If anyone has any insite let me know.

Thanks.

The car is a 5.0 V8 306 GT. 4 Barrel Carb.

grnsleeper

i agree with you sounds like a fuel pump problem.

50powered

sounds like eithier the tfi module on the distributor or the distributor itself. my 88 gt done the same thing so i replaced the module and the dizzy and it fixed the problem. it would be driving fine and out of no where it wold just die out and pick back up immeadiatly.

mjr46

..I don't concure with you^^^^ why..it's carbuerated and should have an external fuel pump unless some one converted to electric...mechanical pump doesn't act that way..so I disagree strongly on your diagnosis

mjr46

...and you my sir are definately way off base^^^^^^ wrong wrong and more wrong.....a 85 gt is carb'ed and does not use a efi type dizzy with a tfi module 86-95 mustangs do...so he has no tfi module to go bad............so now that we have cleared up the misinformation in the last two posts......what type of ignition do you have????stock still??? if so it is duraspark.......my first bet would be the duraspark box itself is bad....I have a whole pile of them that do exactly what you say...they cut off and then back on very quickly.....if that doesn't cure it and all wiring and connections are good..my next guess would be the stator/pick up in the dizzy

oh actually let me correct myself .....84-85 did have tfi modules on the dizzy but those were only on cfi equipped automatic 5.0 mustangs......the carb'ed stangs used duraspark

XXC

No, it's not the stock ignition, it's MSD.

MSD Box and Ignitor Coil..

They could be bad, but there not really that old.. They were already replaced once before.

Kumdie

You are not alone.. Im driving and as long as I steadily pressing the accelerator I can come up through the RPM's but when you are really getting into it and mash the gas it just starts putt'ing or cuts itself out! I have a 1994 Mustang with a 5.0 HO I replaced the MAF because I figured if the sensor was bad it would say hey too much air dump more gas. It helped out a lot! atleast I can get it past 3500 without it feeling like it cut out but still I want my acceleration.

mjr46

what kind of distributor you using?? factory duraspark one??? if so it may be the pick up/stator then

FuzzyDiceRule

check the dizzy rotor, i had this happen to me, but on a much faster area of time. I was at my friends house, and i started her up to leave, and it wouldnt rev, it would like resist, but it would rev up when moving. and then on the way home, what you describe happened, twice, and then the car died at an intersection and wouldnt start, mechanic pulled the dizzy and found a hole in the rotor

XXC

Ah, it's factory..

Think I should throw a MSD in ?