i was driving home from school tonight and my truck started hesitating and jerking.....really only did it noticably under 2000 rpms, but above 2000 rpms it did it a little bit, but not bad......it did this a few days ago and it quit after i let it set for about an hour......i let it set for about 3 hours tonight and it started doing it again after i tried to drive it again.....when it idles it runs at about 500 rpm were it usually idles around 900 rpm....and the oil pressure is dropping well below 25 psi like the truck is trying to shut off....

could this be my tranny saying bye bye? or is it something with the engine? is this an IAC going bad?

 

Dont know if this is even close to being related but mine was doin the same thing. Would idle way low and be way jerky/hesitant almost like it needed a serious tune up. Turned out it was a big tear in a vacum line on the positive crank ventilation system. Works great now.

 

if you are driving as in moving while it does this it isnt the IAC, maybe spark plugs or wires?

 

just replaced them about 8000 miles ago with motorcraft parts......

 

make sure they didnt come in contact with heat and what not...

IAC wouldnt do it unless you were sitting still and under idle.. ie in D, R, 1, 2. Not Park or Neutral.

 

Clean your MAF if you have one, I would get some carb cleaner too and clean out ur intake manifold. Also it could be a loss in fuel pressure, whens the last time you changed the filter? Could be slowly starting to die, not enough to kill the engine, but enough that its not gettin enough fuel to the cylinders.

 

hmm ya know i had this problem in my truck when it was new, took 5 trips to the dealer before they 'found it' (dude spilled his coffee all over the front of his shirt on the way to work with it) hehe serves him right for calling me dilusional. um im not sure but ill take a peak at my reciepts and see if i can find what they replaced.

the feeling is almost like the wheels are locking up and it literally THROWS u out of the seat if ur not wearing ur seat belt when it gets REALLY bad. it also idles all over the place, and makes ur RPMs drop ALOT if u turn anything that draws power on - like ac or head lights.

 

Mine does it every now and then. Matbe this would help since we basically have the same truck. I replaced spark plugs, wires, fuel filter, high test gas, cleaned maf, changed gear oil, etc. It does it from time to time on a low rpm at high speeds.I was talking with a mechanic and said it could be the "tourqe converter" I made a post a month or so ago about mine.

 

hmmmmmm i hope it aint nothing too expensive!

 

he had his replaced on his 1992 F-250 for 2300.00 dalloroo's!!!!! I was like wtf man...........

 

HOLY CRAP! if it is going to cost that much, i will have a manual tranny to put back in there......

 

ya i think thats what it was, the torque converter locking up

 

great....i wonder what that will cost to replace?

 

i dunno but im sure its not cheap. btw, there wont be any codes for it either. atleast there was none for my truck. i had the lil box with the lil red button that u push when the truck misbehaves to tell ya whats going on with it, it didnt show squat. I have come to the conclusion that the computer diagnostics are pretty much useless.

 

If it is bucking that bad, it is obviously something in the drive line. So lets look at what we have there:

Engine... probably not it.
Torque converter... Likely suspect
Transmission... probably not it. They just die.
Transfer case... Nah, it would just blow up.
Differentials... Also would just blow up.
Axles... Nothing to bind up really.
Brakes... We don't have automatic braking systems to malfunction
Wheels & Tires... I think you'd notice that.

 

hmmmmm...would a fuel pump just go bad or would it slowly go out.........

 

fuel pump can slowly die over months, or in a day.

 

i checked it out a little tonight.....i have a miss in the engine.....i am going to pull out the plugs and wires friday and hopefully that is it....but my plugs and wires only have 6,000 miles on them.....i installed them on January 1 of this year....would my coil pack cause this miss in the engine..........i installed Motorcraft plugs and wires that i bought from the dealer....

 

Yes the coil pack could cause a misfire.

 

should i change out the coil pack and see if that solves my miss problem?

 

Do you have one that you could swap out? If so do it.

 

nope...i would have to go buy one....

 

is it a common problem after about 89,000 miles and 10 years?

 

coil pack? whats that? i may try it..............

 

it is what gives your spark plugs spark....it is what the opposite end of your spark plug wire attach to (other end from the plugs)...it is by the intake manafold on the passanger side toward the firewall, on top of the engine....