02 Ranger 3.0 Flex Engine Spuddering

[kmiller7376]

I have a 02 Ranger 3.0 Flex fuel. It has recently started to spudder bad when the RPM's go over 3200. It acts like it wants to turn off. When I release the gas pedal and the rpms' go back below 3000 the truck runs normal as if nothing is wrong. No smoke or anything.

It is not throwing any codes. I'm at a loss here.

 

[Big Jim M]

Start with a new fuel filter.
Big JIm

 

[kmiller7376]

I have all new Plugs/wires, new fuel filter. I also replaced belt tensioner, new serpentine belt.

It feels like the engine is cutting in and out.

 

[Big Jim M]

Cap? Rotor? What off brand plugs did you use? What gap is in them plugs?
Big JIm

 

[JP02XLT]

I would check the fuel pump pressure, or possibly look at the injectors for issues (Dirty) other than that another really slim possibility is that the ECM is somehow activating the RPM redline which I believe is 3000 rpm on a stock 3.0 ecm, but that is limited to neutral or park for an Automatic. You could try to disconnect the battery & let it sit for 30 minutes or so, to let the ECM reset itself. Are you sure you have all the plug wires on the coil in the correct firing order?

No cap or rotor on an 02.

JP02XLT

 

[TomB1269]

If this is happening in gear, it is most likely a syncro shaft failing. Do you have the annoying belt like whine? Take the belt off and start it. If it whines, its the syncronizer shaft. The syncronizer is not monitored for fault codes over 2500 rpm, IE mis-fire/bucking feeling without a code flashing.