'mornin all,

I've got a question regarding possible diagnosis on an engine hesitation that I seem to have.

I've done all the typical things like change EGR valve and sensor, cap, rotor, plugs, wires, all three fuel pumps (which were bad, or going there), filter, and the truck runs pretty well. I'm noticing a slight hesitation when I'm just maintaining throttle in any gear. When I'm under load like accelerating, I can't notice it at all, but when you reach speed and let off the pedal enough to level out, there's a slight hesitation. It almost seems like timing is just a tad off, and I'm going to time it to see if that's it, but I'm not thinking that it is. It runs pretty much as it should with the exception of that minor miss.

Is it possible that the TFI module could be having issues? Or is there another sensor or module that I'm not thinking of that could cause this sort of behavior? I always thought when a TFI module went bad, it did so in a big way, and nothing runs, but maybe I'm wrong.

Anyway, other ideas are always appreciated. 'later

tim

 

A different size orifice in the EGR (one or two sizes down) might resolve your issue. EGR's seem to come in a one-size-fits-all configuration but one size does not necessarily work in all applications. Check with your local, friendly emissions tech about that.