my truck runs good at an idle and at 40 mph and up but shakes horrible when taking off slow or fast, raising the rpms while brake standing, and slow driving. Kinda like a misfire. The engine compartment was hosed down after a nite of mud but it started two days later ands been here for a day or so now. Any thoughts.

 

could be a cop or a drive shaft u-joint. it happens alot when you clean off the modular engines with water. could you fill out everything about your truck so someone else could give you any other ideas?

 

you have a bad coil. They really don't like water especially when they are older and the dielectric grease has went away. eventually you'll get a check engine code or you can got the the dealer and they'll diagnose it for about $60

 

Last time I had a code and no light. Go to Autozone and have the codes checked.

 

Pull the wires/ COP's you've Got mudd sitting in the spark plug chambers and takeing the charge from the Wires...its so little it wont throw a code but its enogh to take about70-80% of the charge going threw the wires... Take the COP's or Wires...witch ever you have and find someone with an aircompresser and blow compressed air into each chamber and watch out because alot of dryed up dirt/ Water WILL fly out. Ive gone mudding in my truck a few times..Every time i get a misfire/ Half misfire...take the plug wires out and blow air into each chamber my truck runs fine after i do that...You got a lil mud/ Water in the chambers taking the charge...Good luck.