99' 5.4 is running bad. It happens at idle and at different speeds such as 5 to 10mph, 45 to 50mph and 65-70mph, etc. A good example is when on the highway going about 45 in 4th gear, I slowdown to pass someone, as I start the medium acceleration the engine feels like its literally stuttering. The entire truck shudders. When I let off to a light acceleration it seems to be fine or if I use heavy acceleration to the point that it downshifts.

I did replace the fuel and air filters. I have had the engine replaced due to piston slap then the #4 coil the day after I received it back from the engine replacement.

Sound familliar?

Richie
rb@mindspring.com

 

It might not be the engine it sort of sounds like the tranny is acting up. Like too much fluid (Air entrainment) Check the fluid and just for kicks reset the puter. While your under the hood check all of the vac hoses and sensor connections and make sure the maf is clean. When you replaced the air filter you might have stirred up some dirt and it got on the maf

good luck-

 

Stupid question here: but what is the MAF?

To add more info, I did have the throttle body cleaned last October.

Also if a tranny issue, would it also happen in drive sitting still?

Richie
rb@mindspring.com

 

MAF=Mass Air Flow sensor What type of air filter do you use?

If you have the stock set up the MAF is in the left side inside the air filter clamshell housing (The half that the filter seals against)

Take the big elbow leading to the airfilter housing off then remove the filter housing the side with the wires going into it has the MAF in it. Look through the hole (From where the big elbow was attached) and you will see a horizontal bar in there with some very small bare wires be very carefule those wires are very delicate. Clean them with Windex and a cue-tip Once done re-set the puter.

Good luck-

 

Problem solved!! The shuddering became worse starting from a standstill. Felt like a cylinder was missing all the time. Made the mistake to stop by the dealer, thought i wouldn't make it home. They diagnosed it as bad #4 coil (here we go again.) They wanted $325.00 to replace one coil and one spark plug and $425.00 to replace the coil and all 8 plugs.

Solution: went to Autozone, bought the coil and the OIDII code reader. Had the P0403 code (Cylinder 4 Misfire.) 30 minutes and a few band-aids later, coil is replaced and no codes. Also checked the hose clamp directly above the coil, sure enough it was loose, fluid dropped as i was adjusting it. Added 2nd hose clamp to correct issue.

Richie
rb@mindspring.com

 

good catch raptor! I forgot about the #4 coil pack and the leaking heater hose!

glad to see you did it yourself too!

peace-