Dodge Repair: Not starting was running rich and ruff

Question
Roland, Thank you for the shoulder to cry on. I have a regular 2001 Dodge Caravan with a 3.3 engine that has 123,000 miles. When it ran it ran very sooty leaving a black soot spot on the ground.
While driving it would buck. It reads the P1684 code in the dash for the battery I recently replaced. But when I turn on off on off on it also beeps five times then after a 4 second pause it beeps once.  Plugs are continuing to become very wet so replaced with new ones. Even when using starting fluid they still become gasoline fouled. This car has had this type of problem ever since I bough it about one year ago.  Can you please reply to this message with some First Aid. Thank you for what you do. Ron

Answer
Hi Ron,
A no start with no fault codes is a bit of a challenge, but given the info you hared
there is one part that you could check out yourself now which could be involved and also is not well sensed by the powertrain control module (pcm) and that part is the exhaust gas recirculation valve (egr valve). It is located near and under the throttle body and is connected to a narrow gauge exhaust pipe that branches off from the center of the right cylinder bank's exhaust manifold. When you find it notice that it has a round top with a vacuum hose and then a flange area between that and the valve proper. Hidden behind that flange is the valve's stem which has a circumferential slot. Insert the tip of a screwdriver in the slot and use that to move the stem back and forth. These is internal spring-action which attempts to close the valve. When the stem gets gummed up due to the exhaust gases that it handles that may keep the valve from closing tightly and then the mixture is too lean which prevents idling and could also cause soot if the mixture is un-burned. So spray some WD-40 on the stem where it enters the valve body and then move the stem back and forth to loosen the action. See if that helps to get it to start again, and ideally also improve the running/soot issue.

Other than that I would wonder whether the fuel pressure regulator (a purely mechanical part found in the fuel tank module) might be running above the specified level of 58 psi. It is not controlled in any way by the powertrain control module so its not going to be noticed as a fault code if that were the case.
I don't see there to be an access port to connect a pressure gauge to, so one would need an adapter hose with such a port to do a reading. I can't think of anything else that would cause it to run rich and still have the absence of any fault codes. I wonder though if it is running that rich why the pcm isn't getting info about that from one of the heated oxygen sensors in the exhaust stream and thus putting out a "too rich" fault code?
The fact that it does report a fault code suggests that the pcm is working properly as far a fault code reporting goes.
I haven't seen any mention of beeps as part of the fault code readout procedures.
So maybe it would be worth having a shop check out the fuel pressure.
Roland