Chrysler Repair: 2003 Dodge Caravan: Difficult fuel tank filling, 4 digit numbers, dodge caravan

Question
Hi Roland!2003 Dodge Caravan.I had trouble filing the gas tank.Kept shutting off the pump.If I pumped REAL slow it would accept fuel.Try and fill it full pressure like normally do it would keep shutting pump off.Is there a vent or something that would cause this to happen?just started doing this.Thank you,Mark

Answer
Hi Mark,
There is a check valve in the filler pipe which is part of a complex system that is designed to capture vapors that occur when filling the tank. I can't say for sure why you have this experience but there are several components which might be implicated as the cause of the problem. My first suggestion would be to go to an Autozone Parts store or similar chain which offers to do free readouts of the engine computer memory for stored fault codes, which are 4-digit numbers preceded by a P. Get the specific numbers, ask what they mean, then tell me what you learned and we can check it against the service manual.
In the meantime the '02 manual admits to this sort of situation but doesn't offer a long-term fix:

"If the engine is shut-off while the On-Board diagnostics is running, low level tank pressure can be trapped in the fuel tank and fuel can not be added to the tank until the pressure is relieved. This is due to the leak detection pump closing the vapor outlet from the top of the tank and the one-way check valve not allowing the tank to vent through the fill tube to atmosphere. Therefore,  when fuel is added, it will back-up in the fill tube and shut off the dispensing nozzle. The pressure can be eliminated in two ways.
1. Vehicle purge must be activated and for a long enough period to eliminate the pressure.
2. Removing the fuel cap and allowing enough time for the system to vent thru the recirculation tube."

It is also possible that the recirc tube is impaired. You might try waiting for a bit before starting the fill process, would be worth experimenting with. I don't know whether the driver can initiate the purge, or perhaps there is a fault with the purge pump which will be shown by the fault code readout.
But see if there is a fault code and let me know.
Roland


Roland