PULSATION UNDER LIGHT THROTTLE

[vik singh]

Hi, I have a 01 ST and i feel some hesation under light trottle.. I have checked my spark plugs and wires and fuel filter..Any ideas what it can be?

 

[EddieS'04]

May need to clean the mass air sensor...do a search for how to...I think there is a project about it in that section...

 

[Jerry Bradfield]

Good luck, with that problem.

I have a 2004 with just undr 20,000 miles on it & I have been battling this

problem since right after I purchased my ST. The ( 4 ) dealerships that I have taken

it to have performed the transmission fluid additive update, changed some solenoids & a valve in the transmission,they have updated/reprogrammed my computer twice,no one can seem to find out what is causing this pulsation under light loads ( whenever engine is cold after startup ).

It does it for about 5 to 10 minutes everytime I start up the truck, I can feel it through all the gears and even after it goes into overdrive.The dealerships keep teeloing me that it is an ongoing problem

with the 4.0 V6s in the Sport Tracs,I have had it at differant dealerships ( 8 ) times since I bought truck.I called Ford Motor Company the last time i took it in & Ford told me that they are aware of the problem & are working to resolve the issue, but as of yet, they have not come up to a solution.

The things that I have tried myself have been to: change the IAC valve, DPFE valve, emission elbow,

coolant temp sensor(for the computer) & clean the MAF sensor, each time I have changed or did anything, I reset my compter by disconnecting my battery for 10 to 15 minutes each time.

Still no luck with my problem, I have just about decided to trade it in and get a 2006 F150.

So, again good luck with that problem, I hope you have better luck than me.

 

[Robert Cuenca]

i have had that prob on my 03 xlt premium as well. it happens when cruising about 30mph and very very light foot on the throttle, less than 2000 rpms. i get a lot of hesitations, sputters, etc. it quits onces i give it more gas. i considered this normal. it doesnt happen enough to annoy me becuase its only at that one sweet spot that i dont always hit.

 

[David Crockett]

I notice this issue with my '05 ST very rarely. I get what feels like a slight vibration through the gas pedal when ever I accelerate through curves from a stop (such as when parked at an intersection). The vibration is also usually accompanied by a vibrating sound that has a plistic-sounding quality to it. It is enough for me to notice, but i haven't experienced a loss of power or acceleration from it, and it usually only lasts for a few seconds. I doubt I'll investigate further, unless someone here thinks I should.



DD