2005 Dodge Caravan has a miss without a check engine light

For three months my caravan with the 3.3 V/6 has a miss while cruising at a constant speed, mostly at low speeds (25 to 35 mph) and low RPMs (1500 minus). No check engine comes on. I've had two different Dodge service centers look it over and have done the following with no improvement.

-both spark plugs and wires replaced

-fuel injector flush has been done No improvement and they have no idea what's causing it. They say that until a check engine comes on, they won't know what do fix. My concern is that there is no way to know when the check engine light will come on and the problem is very slowly getting worse and is driving me crazy. Has anyone experienced the same thing and have figured out what the problem was and more importantly, what the fix is.

Are these Dodge Dealer Service Centers?

For what it's worth, when I worked at an independent auto shop (2001), the diagnostics software we used was sophisticated enough to do a "misfire count" while we drove the vehicle. If it was an ignition-related problem, it sure made the diagnostic end quick and easy for any Joe in the garage -- and I'd find it hard to believe that this level of technology (or it's 2003/6 replacement) isn't available from a computer interface designed to work with Dodges (as opposed to the Autozone/Midas fault code reading). If it wasn't ignition related, it was easy for the tech to review the data on the monitor and start from there.

If the shops have taken the car in and have been able to replicate the problem, I would have a hard time accepting the 'no code, no fix' excuse.

If you've been taking it to a lower-level shop (though you make it sound like it's the dealer...) that doesn't have the manpower or sophistication to help you, then you know what the next step is.

J> For three months my caravan with the 3.3 V/6 has a miss while cruising