herky-jerky & sluggish

[angi1]

Hi.
Within the past few months my mustang has been running horribly. More specifically, the acceleration has become really sputtery. Almost like the something is clogging up the fuel system. It's not really bad when I accelerate fairly slow and steady, But when I accelerate hard, or especially when I let off the gas a bit, then re-accelerate - the car becomes really sluggish and herky-jerky.(possible transmission problem?)

It's been this way for months. I've tried the fuel system/ fuel injector gas treatments multiple times to no avail.

I took it to the Ford dealership where I get it serviced. I was told that everything appeared to be fine when it was checked out. His best guess at the problem was a bad PCV valve. So he replaced that. But it didn't help.

I've had the fuel filter, air filter, & spark plugs all replaced within the last year or two, so I doubt any of those are the problem.

I'm at my wits end - especially when even the Ford guy doesn't seem to have a clue.
Anyone have any insight as to what might be wrong???? Thanks, Ang

2003 mustang
3.8L v6
automatic
only 37,000 miles

 

[Skymarshal]

Boy, I don't know. the fuel filter and air filter are the usual culprits. Maybe get some contact cleaner or MAF cleaner and clean your MAF sensor.

Try putting the tranny in low and while driving at about 2000 RPM, hammer it and see if it still shudders. That might help rule out a problem with the tranny upshifting. If the engine shudders at the same RPM in Drive, it might also be your torque converter.

 

[Shano2001]

As i posted in an other topic sounding somewhat like this i had a truck where the CAT was semi plugged and unless i accelerated REALLY slow stuff that was broken off inside the cat would plug it solid.. Check you CAT would be my guess

 

[MustangLX-5.0]

CAT is a good guess but at only 37,000 miles I highly doubt it.CAT's usually don't start plugging up or showing inefficiencies until usually over 120K miles.I'm gonna go with what Skymarshal said and clean your MAF sensor out.CRC makes a MAF cleaner but I found that the QD Electronic Cleaner has the exact same chemicals as MAF cleaner...and it cost almost 2 bucks less.You'll have to remove the MAF tube from the black air housing then spray in both sides.Make sure to spray the tiny wire (looks like tiny bulb filament).

Other problems could be your plug wires,or even dirty injectors.Those fuel additives don't do a whole lot of good unless you added them at an interval of every other fill up/Even then,it only gets newly formed deposits,not stuff thats been stuck on and built up.I would reccomend an induction cleaning (injector flush).Have it done at a Ford dealer or your nearest auto repair shop.

Other suspect could be a faulty coil pack.One or two cylinders could be shorting out at the coil under a heavy load.First,clean your MAF,check your wires and your coil pack before you think about the injector clean.

 

[Shano2001]

CAT is a good guess but at only 37,000 miles I highly doubt it.CAT's usually don't start plugging up or showing inefficiencies until usually over 120K miles.I'm gonna go with what Skymarshal said and clean your MAF sensor out.CRC makes a MAF cleaner but I found that the QD Electronic Cleaner has the exact same chemicals as MAF cleaner...and it cost almost 2 bucks less.You'll have to remove the MAF tube from the black air housing then spray in both sides.Make sure to spray the tiny wire (looks like tiny bulb filament).

Other problems could be your plug wires,or even dirty injectors.Those fuel additives don't do a whole lot of good unless you added them at an interval of every other fill up/Even then,it only gets newly formed deposits,not stuff thats been stuck on and built up.I would reccomend an induction cleaning (injector flush).Have it done at a Ford dealer or your nearest auto repair shop.

Other suspect could be a faulty coil pack.One or two cylinders could be shorting out at the coil under a heavy load.First,clean your MAF,check your wires and your coil pack before you think about the injector clean.

Woops ! didnt see the mileage lol! but yes i did have a prob with my coil pack ! it would sputter and not even run proper at all ! they are the same as some taurus . i went and got one off a 97 i belive. mine was a 96 mustang though.

 

[Shano2001]

If still no luck i can always ask my dad he used to be a mechanic

 

[angi1]

Thanks a lot for all the insight. I feel a bit better now that I have a list of possible culprits to check into. I definitely go down the list, and hopefully one of them solves the problem. Thanks again.