I am having a problem. When I am driving around 20mph in traffic let my foot off the gas and try to accerate at a slow speed my truck start to vibrate very bad causing the whole truck to shake. If you accerate at a high speed it dose not do that as bad. At idle speed it runs just a little rough (not bad at all). at 30 and 40 dose the same thing but nowhere near what it dose at 20. Also just to let you know that I live in the Mid-West (Snowing now) What could be causing this??

One more question do all truck have a Tach wire??

My truck is a 1993 F-150.

PLEASE HELP

 

I think we need more information for that: what engine, fuel injected or carburated, is the ignition system (dist. cap, wires, plugs) ok, what about air/fuel filter, pcv valve etc.
If intake/exhaust are free and all cylinders get spark, the remaining main components are fuel delivery, timing and emissions.

 

Fuel Injection. Plugs wire and cap replaced about 6 months ago. Air filter replace about 3 months ago. Fuel filter not done yet. PVC Valve not done yet. How do I check intake/Exhaust? Yet to check spark. this started a couple of days ago and right now we have "near billiard" conditions.

 

Chappy,
I'd almost be willing to bet that either you have a lose plug wire on the distributor or you have moisture in the cap.
I had an '87 F150 5.0 that did that and the intake was completely filthy.. almost clogged. I wouldn't think a '93 would have that problem just yet.

Just my suggestions.

------------------
KV
-----
'97 F150 SuperCab 4.6L Auto 2WD
Burgandy
Nerf Bars
Cat Back exhaust with Magnaflo dual 3" pipes
and tipsout the back.
SuperChip
K&N Drop-In Filter
Bosch Platinum +4 spark plugs
1/4 16.747 @81.73 (this will improve)
Track Time Pics

 

OK, I bought new PVC, Fuel Filter, Wires and Plugs cap and rotor. Will try these first.

 

Ever check your U-joints lately???

------------------
1999 F150 4x4 XLT BLACK ORP 4.6 5 SPEED 3.55
LUND HOOD SHEILD
K&N
FLOWMASTER SERIES 40 SINGLE OUTLET
CAPTAIN CHAIRS
PIONEER 6815's(for now)
SUPERCHIP
AIRBOX MOD
WAAG BRUSH GUARD
SPIRALMAX
KENWOOD 9015
SUPERCHIP STICKERS
MTX THUNDERFORM
KICKER 240 AMP
PIAA 9007'S

 

Replace U joints 2 months ago when the rear one broke.

Thanks for the thought keep them coming. I am going to replace the items now. Let you know if it works or not.

 

Replace plugs, wire, cap, and rotor. Replace PVC value. Attemped to replace fuel filter but did not have the tool to remove the connection (Thanks Ford). Good new it back to normal.

Thanks all for the help.