Hey guys thanks in advance for any suggestions.I have a 97 f 150 with 4.6 4x4 after running 70 -75mph on the interstatewhen I come to a stop and truck has a rough idle. Then when I pull out it falls on its face till i get to between 2800-3100 rpm then it picks up ok sort of feels like an old 2 stroke dirt bike when the powerband kicks in.I replaced plugs and wires(motorcraft)6000miles ago for misfire#1 cyl.this problem didnt go away with the plugs and wires.have had this since I bought it used.Doesnt always do it but more and more recently.last week check engine light came on but went out on its own the next day.Thanks again

 

The code should still be in memory. Find out what it is and it will help you figure out what is going on with your truck. I believe Auto Zone will pull your codes for free. (Don't quote me) Good luck. Let us know what you find.

 

this happened with the light coming on then off before the plug/wire job and no code was found in the memory only the misfire ,but may just stop and see if they will do it anyhow.Thanks

 

I have a 2000 4.6, and I thought I had the issue - replaced plugs, fuel filter, did a sea foam cleaning, leaned the egr and throttle body, installed magnaflow exhaust, and a k&n...still did nothing....

then, somebody expained to me the physics / psychological phenoma that occurs when moving at 75mph for a sustained period of time, and then moving at 35mph. your body feels like you are going very slow after cruising that long at a high speed...if you cruised all day at 15mph, and then accelerated to above 15 the truck would feel faster b/c your body was used to 15mph.

just a thought, and a free fix if you think my thoughts are stupid, you may try w/ a fuel filter change, especially if you bought the truck used, and also an air filter b/c a clogged air filter can cause what you are describing, b/c you can't get air at low speed / rpm.