I bought a 1996 Ranger 3.0 from a dealer with 60k miles. It's real clean but after driving a while, I noticed it idles very rough. While waiting at a light, I can feel the truck shaking back and forth. It runs great otherwise. I brought it back within warrantee period 2 times for a total of 6 days. Honda dealer sent it to the local Ford dealer where they replaced the air sensor. They tell me nothing is wrong with it...the computer shows nothing...but it idles exactly the same. Is this normal? Is there anything I can do to smooth the idle? It drives me crazy.
Thanks for any help.

 

Duke 21:

Check the back threads as there have been many with rough idle and other driveability problems. Many have been solved easily others took a little more effort.

First thing that I would check is for any vacuum lines that may have fallen off or are leaking (hiss). Second, check your EGR valve to ensure that it is opening and closing properly. Lastly, with the truck in the complete dark like inside the garage with the lights off, open the hood with the engine running and watch for sparks/arcs from the ignition wires. Could have one or two that are "leaking" to ground.

Keep us posted on your progress.

Russ

 

duke21 ...Welcome to Ford Truck Enthusiasts!

Russ has suggested a good troubleshooting plan.

If you still are having problems after that, you may also want to consider cleaning your MAF and your Idle Air Control Valve.